ONOS checkin based on commit tag e796610b1f721d02f9b0e213cf6f7790c10ecd60

Change-Id: Ife8810491034fe7becdba75dda20de4267bd15cd

47 files changed, 8392 insertions, 0 deletions

diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ArpHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ArpHandler.java
new file mode 100644
index 00000000..6ca6d193
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ArpHandler.java
@@ -0,0 +1,216 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.ARP;
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.IpAddress;
+import org.onlab.packet.MacAddress;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Host;
+import org.onosproject.net.Port;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.packet.DefaultOutboundPacket;
+import org.onosproject.net.packet.InboundPacket;
+import org.onosproject.net.HostId;
+import org.onosproject.net.packet.OutboundPacket;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class ArpHandler {
+
+    private static Logger log = LoggerFactory.getLogger(ArpHandler.class);
+
+    private SegmentRoutingManager srManager;
+    private DeviceConfiguration config;
+
+    /**
+     * Creates an ArpHandler object.
+     *
+     * @param srManager SegmentRoutingManager object
+     */
+    public ArpHandler(SegmentRoutingManager srManager) {
+        this.srManager = srManager;
+        this.config = checkNotNull(srManager.deviceConfiguration);
+    }
+
+    /**
+     * Processes incoming ARP packets.
+     * If it is an ARP request to router itself or known hosts,
+     * then it sends ARP response.
+     * If it is an ARP request to unknown hosts in its own subnet,
+     * then it flood the ARP request to the ports.
+     * If it is an ARP response, then set a flow rule for the host
+     * and forward any IP packets to the host in the packet buffer to the host.
+     *
+     * @param pkt incoming packet
+     */
+    public void processPacketIn(InboundPacket pkt) {
+
+        Ethernet ethernet = pkt.parsed();
+        ARP arp = (ARP) ethernet.getPayload();
+
+        ConnectPoint connectPoint = pkt.receivedFrom();
+        PortNumber inPort = connectPoint.port();
+        DeviceId deviceId = connectPoint.deviceId();
+        byte[] senderMacAddressByte = arp.getSenderHardwareAddress();
+        Ip4Address hostIpAddress = Ip4Address.valueOf(arp.getSenderProtocolAddress());
+
+        srManager.routingRulePopulator.populateIpRuleForHost(deviceId, hostIpAddress, MacAddress.
+                valueOf(senderMacAddressByte), inPort);
+
+        if (arp.getOpCode() == ARP.OP_REQUEST) {
+            handleArpRequest(deviceId, connectPoint, ethernet);
+        } else {
+            srManager.ipHandler.forwardPackets(deviceId, hostIpAddress);
+        }
+    }
+
+    private void handleArpRequest(DeviceId deviceId, ConnectPoint inPort, Ethernet payload) {
+
+        ARP arpRequest = (ARP) payload.getPayload();
+        HostId targetHostId = HostId.hostId(MacAddress.valueOf(
+                arpRequest.getTargetHardwareAddress()));
+
+        // ARP request for router
+        if (isArpReqForRouter(deviceId, arpRequest)) {
+            Ip4Address targetAddress = Ip4Address.valueOf(arpRequest.getTargetProtocolAddress());
+
+            sendArpResponse(arpRequest, config.getRouterMacForAGatewayIp(targetAddress));
+        // ARP request for known hosts
+        } else if (srManager.hostService.getHost(targetHostId) != null) {
+            MacAddress targetMac = srManager.hostService.getHost(targetHostId).mac();
+            sendArpResponse(arpRequest, targetMac);
+
+        // ARP request for unknown host in the subnet
+        } else if (isArpReqForSubnet(deviceId, arpRequest)) {
+            flood(payload, inPort);
+        }
+    }
+
+
+    private boolean isArpReqForRouter(DeviceId deviceId, ARP arpRequest) {
+        List<Ip4Address> gatewayIpAddresses = config.getSubnetGatewayIps(deviceId);
+        if (gatewayIpAddresses != null) {
+            Ip4Address targetProtocolAddress = Ip4Address.valueOf(arpRequest
+                    .getTargetProtocolAddress());
+            if (gatewayIpAddresses.contains(targetProtocolAddress)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean isArpReqForSubnet(DeviceId deviceId, ARP arpRequest) {
+        return config.getSubnets(deviceId).stream()
+                     .anyMatch((prefix)->
+                     prefix.contains(Ip4Address.
+                                     valueOf(arpRequest.
+                                             getTargetProtocolAddress())));
+    }
+
+    /**
+     * Sends an APR request for the target IP address to all ports except in-port.
+     *
+     * @param deviceId Switch device ID
+     * @param targetAddress target IP address for ARP
+     * @param inPort in-port
+     */
+    public void sendArpRequest(DeviceId deviceId, IpAddress targetAddress, ConnectPoint inPort) {
+
+        byte[] senderMacAddress = config.getDeviceMac(deviceId).toBytes();
+        byte[] senderIpAddress = config.getRouterIp(deviceId).toOctets();
+
+        ARP arpRequest = new ARP();
+        arpRequest.setHardwareType(ARP.HW_TYPE_ETHERNET)
+                  .setProtocolType(ARP.PROTO_TYPE_IP)
+                  .setHardwareAddressLength(
+                        (byte) Ethernet.DATALAYER_ADDRESS_LENGTH)
+                  .setProtocolAddressLength((byte) Ip4Address.BYTE_LENGTH)
+                  .setOpCode(ARP.OP_REQUEST)
+                  .setSenderHardwareAddress(senderMacAddress)
+                  .setTargetHardwareAddress(MacAddress.ZERO.toBytes())
+                  .setSenderProtocolAddress(senderIpAddress)
+                  .setTargetProtocolAddress(targetAddress.toOctets());
+
+        Ethernet eth = new Ethernet();
+        eth.setDestinationMACAddress(MacAddress.BROADCAST.toBytes())
+                .setSourceMACAddress(senderMacAddress)
+                .setEtherType(Ethernet.TYPE_ARP).setPayload(arpRequest);
+
+        flood(eth, inPort);
+    }
+
+    private void sendArpResponse(ARP arpRequest, MacAddress targetMac) {
+
+        ARP arpReply = new ARP();
+        arpReply.setHardwareType(ARP.HW_TYPE_ETHERNET)
+                .setProtocolType(ARP.PROTO_TYPE_IP)
+                .setHardwareAddressLength(
+                        (byte) Ethernet.DATALAYER_ADDRESS_LENGTH)
+                .setProtocolAddressLength((byte) Ip4Address.BYTE_LENGTH)
+                .setOpCode(ARP.OP_REPLY)
+                .setSenderHardwareAddress(targetMac.toBytes())
+                .setSenderProtocolAddress(arpRequest.getTargetProtocolAddress())
+                .setTargetHardwareAddress(arpRequest.getSenderHardwareAddress())
+                .setTargetProtocolAddress(arpRequest.getSenderProtocolAddress());
+
+        Ethernet eth = new Ethernet();
+        eth.setDestinationMACAddress(arpRequest.getSenderHardwareAddress())
+                .setSourceMACAddress(targetMac.toBytes())
+                .setEtherType(Ethernet.TYPE_ARP).setPayload(arpReply);
+
+
+        HostId dstId = HostId.hostId(MacAddress.valueOf(
+                arpReply.getTargetHardwareAddress()));
+        Host dst = srManager.hostService.getHost(dstId);
+        if (dst == null) {
+            log.warn("Cannot send ARP response to unknown device");
+            return;
+        }
+
+        TrafficTreatment treatment = DefaultTrafficTreatment.builder().
+                setOutput(dst.location().port()).build();
+        OutboundPacket packet = new DefaultOutboundPacket(dst.location().deviceId(),
+                treatment, ByteBuffer.wrap(eth.serialize()));
+
+        srManager.packetService.emit(packet);
+    }
+
+    private void flood(Ethernet request, ConnectPoint inPort) {
+        TrafficTreatment.Builder builder;
+        ByteBuffer buf = ByteBuffer.wrap(request.serialize());
+
+        for (Port port: srManager.deviceService.getPorts(inPort.deviceId())) {
+            if (!port.number().equals(inPort.port()) &&
+                    port.number().toLong() > 0) {
+                builder = DefaultTrafficTreatment.builder();
+                builder.setOutput(port.number());
+                srManager.packetService.emit(new DefaultOutboundPacket(inPort.deviceId(),
+                        builder.build(), buf));
+            }
+        }
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultRoutingHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultRoutingHandler.java
new file mode 100644
index 00000000..8b447af4
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultRoutingHandler.java
@@ -0,0 +1,551 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.Ip4Prefix;
+import org.onlab.packet.IpPrefix;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.MastershipRole;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class DefaultRoutingHandler {
+
+    private static Logger log = LoggerFactory
+            .getLogger(DefaultRoutingHandler.class);
+
+    private SegmentRoutingManager srManager;
+    private RoutingRulePopulator rulePopulator;
+    private HashMap<DeviceId, ECMPShortestPathGraph> currentEcmpSpgMap;
+    private HashMap<DeviceId, ECMPShortestPathGraph> updatedEcmpSpgMap;
+    private DeviceConfiguration config;
+    private final Lock statusLock = new ReentrantLock();
+    private volatile Status populationStatus;
+
+    /**
+     * Represents the default routing population status.
+     */
+    public enum Status {
+        // population process is not started yet.
+        IDLE,
+
+        // population process started.
+        STARTED,
+
+        // population process was aborted due to errors, mostly for groups not
+        // found.
+        ABORTED,
+
+        // population process was finished successfully.
+        SUCCEEDED
+    }
+
+    /**
+     * Creates a DefaultRoutingHandler object.
+     *
+     * @param srManager SegmentRoutingManager object
+     */
+    public DefaultRoutingHandler(SegmentRoutingManager srManager) {
+        this.srManager = srManager;
+        this.rulePopulator = checkNotNull(srManager.routingRulePopulator);
+        this.config = checkNotNull(srManager.deviceConfiguration);
+        this.populationStatus = Status.IDLE;
+        this.currentEcmpSpgMap = Maps.newHashMap();
+    }
+
+    /**
+     * Populates all routing rules to all connected routers, including default
+     * routing rules, adjacency rules, and policy rules if any.
+     *
+     * @return true if it succeeds in populating all rules, otherwise false
+     */
+    public boolean populateAllRoutingRules() {
+
+        statusLock.lock();
+        try {
+            populationStatus = Status.STARTED;
+            rulePopulator.resetCounter();
+            log.info("Starts to populate routing rules");
+            log.debug("populateAllRoutingRules: populationStatus is STARTED");
+
+            for (Device sw : srManager.deviceService.getDevices()) {
+                if (srManager.mastershipService.getLocalRole(sw.id()) != MastershipRole.MASTER) {
+                    log.debug("populateAllRoutingRules: skipping device {}...we are not master",
+                              sw.id());
+                    continue;
+                }
+
+                ECMPShortestPathGraph ecmpSpg = new ECMPShortestPathGraph(sw.id(), srManager);
+                if (!populateEcmpRoutingRules(sw.id(), ecmpSpg)) {
+                    log.debug("populateAllRoutingRules: populationStatus is ABORTED");
+                    populationStatus = Status.ABORTED;
+                    log.debug("Abort routing rule population");
+                    return false;
+                }
+                currentEcmpSpgMap.put(sw.id(), ecmpSpg);
+
+                // TODO: Set adjacency routing rule for all switches
+            }
+
+            log.debug("populateAllRoutingRules: populationStatus is SUCCEEDED");
+            populationStatus = Status.SUCCEEDED;
+            log.info("Completes routing rule population. Total # of rules pushed : {}",
+                    rulePopulator.getCounter());
+            return true;
+        } finally {
+            statusLock.unlock();
+        }
+    }
+
+    /**
+     * Populates the routing rules according to the route changes due to the link
+     * failure or link add. It computes the routes changed due to the link changes and
+     * repopulates the rules only for the routes.
+     *
+     * @param linkFail link failed, null for link added
+     * @return true if it succeeds to populate all rules, false otherwise
+     */
+    public boolean populateRoutingRulesForLinkStatusChange(Link linkFail) {
+
+        statusLock.lock();
+        try {
+
+            if (populationStatus == Status.STARTED) {
+                log.warn("Previous rule population is not finished.");
+                return true;
+            }
+
+            // Take the snapshots of the links
+            updatedEcmpSpgMap = new HashMap<>();
+            for (Device sw : srManager.deviceService.getDevices()) {
+                if (srManager.mastershipService.
+                        getLocalRole(sw.id()) != MastershipRole.MASTER) {
+                    continue;
+                }
+                ECMPShortestPathGraph ecmpSpgUpdated =
+                        new ECMPShortestPathGraph(sw.id(), srManager);
+                updatedEcmpSpgMap.put(sw.id(), ecmpSpgUpdated);
+            }
+
+            log.info("Starts rule population from link change");
+
+            Set<ArrayList<DeviceId>> routeChanges;
+            log.trace("populateRoutingRulesForLinkStatusChange: "
+                    + "populationStatus is STARTED");
+            populationStatus = Status.STARTED;
+            if (linkFail == null) {
+                // Compare all routes of existing ECMP SPG with the new ones
+                routeChanges = computeRouteChange();
+            } else {
+                // Compare existing ECMP SPG only with the link removed
+                routeChanges = computeDamagedRoutes(linkFail);
+            }
+
+            if (routeChanges.isEmpty()) {
+                log.info("No route changes for the link status change");
+                log.debug("populateRoutingRulesForLinkStatusChange: populationStatus is SUCCEEDED");
+                populationStatus = Status.SUCCEEDED;
+                return true;
+            }
+
+            if (repopulateRoutingRulesForRoutes(routeChanges)) {
+                log.debug("populateRoutingRulesForLinkStatusChange: populationStatus is SUCCEEDED");
+                populationStatus = Status.SUCCEEDED;
+                log.info("Complete to repopulate the rules. # of rules populated : {}",
+                        rulePopulator.getCounter());
+                return true;
+            } else {
+                log.debug("populateRoutingRulesForLinkStatusChange: populationStatus is ABORTED");
+                populationStatus = Status.ABORTED;
+                log.warn("Failed to repopulate the rules.");
+                return false;
+            }
+        } finally {
+            statusLock.unlock();
+        }
+    }
+
+    private boolean repopulateRoutingRulesForRoutes(Set<ArrayList<DeviceId>> routes) {
+        rulePopulator.resetCounter();
+        HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> routesBydevice =
+                new HashMap<>();
+        for (ArrayList<DeviceId> link: routes) {
+            // When only the source device is defined, reinstall routes to all other devices
+            if (link.size() == 1) {
+                log.trace("repopulateRoutingRulesForRoutes: running ECMP graph for device {}", link.get(0));
+                ECMPShortestPathGraph ecmpSpg = new ECMPShortestPathGraph(link.get(0), srManager);
+                if (populateEcmpRoutingRules(link.get(0), ecmpSpg)) {
+                    log.debug("Populating flow rules from {} to all is successful",
+                              link.get(0));
+                    currentEcmpSpgMap.put(link.get(0), ecmpSpg);
+                } else {
+                    log.warn("Failed to populate the flow rules from {} to all", link.get(0));
+                    return false;
+                }
+            } else {
+                ArrayList<ArrayList<DeviceId>> deviceRoutes =
+                        routesBydevice.get(link.get(1));
+                if (deviceRoutes == null) {
+                    deviceRoutes = new ArrayList<>();
+                    routesBydevice.put(link.get(1), deviceRoutes);
+                }
+                deviceRoutes.add(link);
+            }
+        }
+
+        for (DeviceId impactedDevice : routesBydevice.keySet()) {
+            ArrayList<ArrayList<DeviceId>> deviceRoutes =
+                    routesBydevice.get(impactedDevice);
+            for (ArrayList<DeviceId> link: deviceRoutes) {
+                log.debug("repopulate RoutingRules For Routes {} -> {}",
+                          link.get(0), link.get(1));
+                DeviceId src = link.get(0);
+                DeviceId dst = link.get(1);
+                ECMPShortestPathGraph ecmpSpg = updatedEcmpSpgMap.get(dst);
+                HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> switchVia =
+                        ecmpSpg.getAllLearnedSwitchesAndVia();
+                for (Integer itrIdx : switchVia.keySet()) {
+                    HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swViaMap =
+                            switchVia.get(itrIdx);
+                    for (DeviceId targetSw : swViaMap.keySet()) {
+                        if (!targetSw.equals(src)) {
+                            continue;
+                        }
+                        Set<DeviceId> nextHops = new HashSet<>();
+                        for (ArrayList<DeviceId> via : swViaMap.get(targetSw)) {
+                            if (via.isEmpty()) {
+                                nextHops.add(dst);
+                            } else {
+                                nextHops.add(via.get(0));
+                            }
+                        }
+                        if (!populateEcmpRoutingRulePartial(targetSw, dst, nextHops)) {
+                            return false;
+                        }
+                        log.debug("Populating flow rules from {} to {} is successful",
+                                  targetSw, dst);
+                    }
+                }
+                //currentEcmpSpgMap.put(dst, ecmpSpg);
+            }
+            //Only if all the flows for all impacted routes to a
+            //specific target are pushed successfully, update the
+            //ECMP graph for that target. (Or else the next event
+            //would not see any changes in the ECMP graphs)
+            currentEcmpSpgMap.put(impactedDevice,
+                                  updatedEcmpSpgMap.get(impactedDevice));
+        }
+        return true;
+    }
+
+    private Set<ArrayList<DeviceId>> computeDamagedRoutes(Link linkFail) {
+
+        Set<ArrayList<DeviceId>> routes = new HashSet<>();
+
+        for (Device sw : srManager.deviceService.getDevices()) {
+            log.debug("Computing the impacted routes for device {} due to link fail",
+                      sw.id());
+            if (srManager.mastershipService.
+                    getLocalRole(sw.id()) != MastershipRole.MASTER) {
+                continue;
+            }
+            ECMPShortestPathGraph ecmpSpg = currentEcmpSpgMap.get(sw.id());
+            if (ecmpSpg == null) {
+                log.error("No existing ECMP graph for switch {}", sw.id());
+                continue;
+            }
+            HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> switchVia =
+                    ecmpSpg.getAllLearnedSwitchesAndVia();
+            for (Integer itrIdx : switchVia.keySet()) {
+                HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swViaMap =
+                        switchVia.get(itrIdx);
+                for (DeviceId targetSw : swViaMap.keySet()) {
+                    DeviceId destSw = sw.id();
+                    Set<ArrayList<DeviceId>> subLinks =
+                            computeLinks(targetSw, destSw, swViaMap);
+                    for (ArrayList<DeviceId> alink: subLinks) {
+                        if ((alink.get(0).equals(linkFail.src().deviceId()) &&
+                                alink.get(1).equals(linkFail.dst().deviceId()))
+                                ||
+                             (alink.get(0).equals(linkFail.dst().deviceId()) &&
+                                     alink.get(1).equals(linkFail.src().deviceId()))) {
+                            log.debug("Impacted route:{}->{}", targetSw, destSw);
+                            ArrayList<DeviceId> aRoute = new ArrayList<>();
+                            aRoute.add(targetSw);
+                            aRoute.add(destSw);
+                            routes.add(aRoute);
+                            break;
+                        }
+                    }
+                }
+            }
+
+        }
+
+        return routes;
+    }
+
+    private Set<ArrayList<DeviceId>> computeRouteChange() {
+
+        Set<ArrayList<DeviceId>> routes = new HashSet<>();
+
+        for (Device sw : srManager.deviceService.getDevices()) {
+            log.debug("Computing the impacted routes for device {}",
+                      sw.id());
+            if (srManager.mastershipService.
+                    getLocalRole(sw.id()) != MastershipRole.MASTER) {
+                log.debug("No mastership for {} and skip route optimization",
+                          sw.id());
+                continue;
+            }
+
+            log.trace("link of {} - ", sw.id());
+            for (Link link: srManager.linkService.getDeviceLinks(sw.id())) {
+                log.trace("{} -> {} ", link.src().deviceId(), link.dst().deviceId());
+            }
+
+            log.debug("Checking route change for switch {}", sw.id());
+            ECMPShortestPathGraph ecmpSpg = currentEcmpSpgMap.get(sw.id());
+            if (ecmpSpg == null) {
+                log.debug("No existing ECMP graph for device {}", sw.id());
+                ArrayList<DeviceId> route = new ArrayList<>();
+                route.add(sw.id());
+                routes.add(route);
+                continue;
+            }
+            ECMPShortestPathGraph newEcmpSpg = updatedEcmpSpgMap.get(sw.id());
+            //currentEcmpSpgMap.put(sw.id(), newEcmpSpg);
+            HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> switchVia =
+                    ecmpSpg.getAllLearnedSwitchesAndVia();
+            HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> switchViaUpdated =
+                    newEcmpSpg.getAllLearnedSwitchesAndVia();
+
+            for (Integer itrIdx : switchViaUpdated.keySet()) {
+                HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swViaMapUpdated =
+                        switchViaUpdated.get(itrIdx);
+                for (DeviceId srcSw : swViaMapUpdated.keySet()) {
+                    ArrayList<ArrayList<DeviceId>> viaUpdated = swViaMapUpdated.get(srcSw);
+                    ArrayList<ArrayList<DeviceId>> via = getVia(switchVia, srcSw);
+                    if ((via == null) || !viaUpdated.equals(via)) {
+                        log.debug("Impacted route:{}->{}", srcSw, sw.id());
+                        ArrayList<DeviceId> route = new ArrayList<>();
+                        route.add(srcSw);
+                        route.add(sw.id());
+                        routes.add(route);
+                    }
+                }
+            }
+        }
+
+        for (ArrayList<DeviceId> link: routes) {
+            log.trace("Route changes - ");
+            if (link.size() == 1) {
+                log.trace(" : {} - all", link.get(0));
+            } else {
+                log.trace(" : {} - {}", link.get(0), link.get(1));
+            }
+        }
+
+        return routes;
+    }
+
+    private ArrayList<ArrayList<DeviceId>> getVia(HashMap<Integer, HashMap<DeviceId,
+            ArrayList<ArrayList<DeviceId>>>> switchVia, DeviceId srcSw) {
+        for (Integer itrIdx : switchVia.keySet()) {
+            HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swViaMap =
+                    switchVia.get(itrIdx);
+            if (swViaMap.get(srcSw) == null) {
+                continue;
+            } else {
+                return swViaMap.get(srcSw);
+            }
+        }
+
+        return null;
+    }
+
+    private Set<ArrayList<DeviceId>> computeLinks(DeviceId src,
+                                                  DeviceId dst,
+                       HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> viaMap) {
+        Set<ArrayList<DeviceId>> subLinks = Sets.newHashSet();
+        for (ArrayList<DeviceId> via : viaMap.get(src)) {
+            DeviceId linkSrc = src;
+            DeviceId linkDst = dst;
+            for (DeviceId viaDevice: via) {
+                ArrayList<DeviceId> link = new ArrayList<>();
+                linkDst = viaDevice;
+                link.add(linkSrc);
+                link.add(linkDst);
+                subLinks.add(link);
+                linkSrc = viaDevice;
+            }
+            ArrayList<DeviceId> link = new ArrayList<>();
+            link.add(linkSrc);
+            link.add(dst);
+            subLinks.add(link);
+        }
+
+        return subLinks;
+    }
+
+    private boolean populateEcmpRoutingRules(DeviceId destSw,
+                                             ECMPShortestPathGraph ecmpSPG) {
+
+        HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> switchVia = ecmpSPG
+                .getAllLearnedSwitchesAndVia();
+        for (Integer itrIdx : switchVia.keySet()) {
+            HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swViaMap = switchVia
+                    .get(itrIdx);
+            for (DeviceId targetSw : swViaMap.keySet()) {
+                Set<DeviceId> nextHops = new HashSet<>();
+
+                for (ArrayList<DeviceId> via : swViaMap.get(targetSw)) {
+                    if (via.isEmpty()) {
+                        nextHops.add(destSw);
+                    } else {
+                        nextHops.add(via.get(0));
+                    }
+                }
+                if (!populateEcmpRoutingRulePartial(targetSw, destSw, nextHops)) {
+                    return false;
+                }
+            }
+        }
+
+        return true;
+    }
+
+    private boolean populateEcmpRoutingRulePartial(DeviceId targetSw,
+                                                   DeviceId destSw,
+                                                   Set<DeviceId> nextHops) {
+        boolean result;
+
+        if (nextHops.isEmpty()) {
+            nextHops.add(destSw);
+        }
+
+        // If both target switch and dest switch are edge routers, then set IP
+        // rule for both subnet and router IP.
+        if (config.isEdgeDevice(targetSw) && config.isEdgeDevice(destSw)) {
+            List<Ip4Prefix> subnets = config.getSubnets(destSw);
+            log.debug("populateEcmpRoutingRulePartial in device {} towards {} for subnets {}",
+                    targetSw, destSw, subnets);
+            result = rulePopulator.populateIpRuleForSubnet(targetSw,
+                                                           subnets,
+                                                           destSw,
+                                                           nextHops);
+            if (!result) {
+                return false;
+            }
+
+            Ip4Address routerIp = config.getRouterIp(destSw);
+            IpPrefix routerIpPrefix = IpPrefix.valueOf(routerIp, IpPrefix.MAX_INET_MASK_LENGTH);
+            log.debug("populateEcmpRoutingRulePartial in device {} towards {} for router IP {}",
+                    targetSw, destSw, routerIpPrefix);
+            result = rulePopulator.populateIpRuleForRouter(targetSw, routerIpPrefix, destSw, nextHops);
+            if (!result) {
+                return false;
+            }
+
+        // If the target switch is an edge router, then set IP rules for the router IP.
+        } else if (config.isEdgeDevice(targetSw)) {
+            Ip4Address routerIp = config.getRouterIp(destSw);
+            IpPrefix routerIpPrefix = IpPrefix.valueOf(routerIp, IpPrefix.MAX_INET_MASK_LENGTH);
+            log.debug("populateEcmpRoutingRulePartial in device {} towards {} for router IP {}",
+                    targetSw, destSw, routerIpPrefix);
+            result = rulePopulator.populateIpRuleForRouter(targetSw, routerIpPrefix, destSw, nextHops);
+            if (!result) {
+                return false;
+            }
+        }
+
+        // Populates MPLS rules to all routers
+        log.debug("populateEcmpRoutingRulePartial in device{} towards {} for all MPLS rules",
+                targetSw, destSw);
+        result = rulePopulator.populateMplsRule(targetSw, destSw, nextHops);
+        if (!result) {
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Populates table miss entries for all tables, and pipeline rules for VLAN
+     * and TACM tables.
+     *
+     * @param deviceId Switch ID to set the rules
+     */
+    public void populateTtpRules(DeviceId deviceId) {
+        rulePopulator.populateTableVlan(deviceId);
+        rulePopulator.populateTableTMac(deviceId);
+    }
+
+    /**
+     * Start the flow rule population process if it was never started. The
+     * process finishes successfully when all flow rules are set and stops with
+     * ABORTED status when any groups required for flows is not set yet.
+     */
+    public void startPopulationProcess() {
+        statusLock.lock();
+        try {
+            if (populationStatus == Status.IDLE
+                    || populationStatus == Status.SUCCEEDED
+                    || populationStatus == Status.ABORTED) {
+                populationStatus = Status.STARTED;
+                populateAllRoutingRules();
+            } else {
+                log.warn("Not initiating startPopulationProcess as populationStatus is {}",
+                         populationStatus);
+            }
+        } finally {
+            statusLock.unlock();
+        }
+    }
+
+    /**
+     * Resume the flow rule population process if it was aborted for any reason.
+     * Mostly the process is aborted when the groups required are not set yet.
+     */
+    public void resumePopulationProcess() {
+        statusLock.lock();
+        try {
+            if (populationStatus == Status.ABORTED) {
+                populationStatus = Status.STARTED;
+                // TODO: we need to restart from the point aborted instead of
+                // restarting.
+                populateAllRoutingRules();
+            }
+        } finally {
+            statusLock.unlock();
+        }
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultTunnel.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultTunnel.java
new file mode 100644
index 00000000..8c6fbe8d
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DefaultTunnel.java
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+import java.util.List;
+import java.util.Objects;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Tunnel class.
+ */
+public class DefaultTunnel implements Tunnel {
+
+    private final String id;
+    private final List<Integer> labelIds;
+
+    private int groupId;
+    private boolean allowedToRemoveGroup;
+
+    /**
+     * Creates a Tunnel reference.
+     *
+     * @param tid  Tunnel ID
+     * @param labelIds Label stack of the tunnel
+     */
+    public DefaultTunnel(String tid, List<Integer> labelIds) {
+        this.id = checkNotNull(tid);
+        this.labelIds = labelIds;
+        //TODO: need to register the class in Kryo for this
+        //this.labelIds = Collections.unmodifiableList(labelIds);
+        this.groupId = -1;
+    }
+
+    /**
+     * Creates a new DefaultTunnel reference using the tunnel reference.
+     *
+     * @param tunnel DefaultTunnel reference
+     */
+    public DefaultTunnel(DefaultTunnel tunnel) {
+        this.id = tunnel.id;
+        this.labelIds = tunnel.labelIds;
+        this.groupId = tunnel.groupId;
+    }
+
+    @Override
+    public String id() {
+        return this.id;
+    }
+
+    @Override
+    public List<Integer> labelIds() {
+        return this.labelIds;
+    }
+
+    @Override
+    public int groupId() {
+        return this.groupId;
+    }
+
+    @Override
+    public void setGroupId(int id) {
+        this.groupId = id;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (o instanceof DefaultTunnel) {
+            DefaultTunnel tunnel = (DefaultTunnel) o;
+            // We compare only the tunnel paths.
+            if (tunnel.labelIds.equals(this.labelIds)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(labelIds);
+    }
+
+    @Override
+    public boolean isAllowedToRemoveGroup() {
+        return this.allowedToRemoveGroup;
+    }
+
+    @Override
+    public void allowToRemoveGroup(boolean b) {
+        this.allowedToRemoveGroup = b;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DeviceConfiguration.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DeviceConfiguration.java
new file mode 100644
index 00000000..d82eb5ec
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/DeviceConfiguration.java
@@ -0,0 +1,404 @@
+package org.onosproject.segmentrouting;
+
+import com.google.common.collect.Lists;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.Ip4Prefix;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.MacAddress;
+import org.onosproject.segmentrouting.grouphandler.DeviceProperties;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.PortNumber;
+import org.onosproject.segmentrouting.config.NetworkConfig.SwitchConfig;
+import org.onosproject.segmentrouting.config.NetworkConfigManager;
+import org.onosproject.segmentrouting.config.SegmentRouterConfig;
+import org.onosproject.segmentrouting.config.SegmentRouterConfig.Subnet;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Segment Routing configuration component that reads the
+ * segment routing related configuration from Network Configuration Manager
+ * component and organizes in more accessible formats.
+ *
+ * TODO: Merge multiple Segment Routing configuration wrapper classes into one.
+ */
+public class DeviceConfiguration implements DeviceProperties {
+
+    private static final Logger log = LoggerFactory
+            .getLogger(DeviceConfiguration.class);
+    private final List<Integer> allSegmentIds = new ArrayList<Integer>();
+    private final HashMap<DeviceId, SegmentRouterInfo> deviceConfigMap = new HashMap<>();
+    private final NetworkConfigManager configService;
+
+    private class SegmentRouterInfo {
+        int nodeSid;
+        DeviceId deviceId;
+        Ip4Address ip;
+        MacAddress mac;
+        boolean isEdge;
+        HashMap<PortNumber, Ip4Address> gatewayIps;
+        HashMap<PortNumber, Ip4Prefix> subnets;
+        List<SegmentRouterConfig.AdjacencySid> adjacencySids;
+    }
+
+    /**
+     * Constructor. Reads all the configuration for all devices of type
+     * Segment Router and organizes into various maps for easier access.
+     *
+     * @param configService handle to network configuration manager
+     * component from where the relevant configuration is retrieved.
+     */
+    public DeviceConfiguration(NetworkConfigManager configService) {
+        this.configService = checkNotNull(configService);
+        List<SwitchConfig> allSwitchCfg =
+                this.configService.getConfiguredAllowedSwitches();
+        for (SwitchConfig cfg : allSwitchCfg) {
+            if (!(cfg instanceof SegmentRouterConfig)) {
+                continue;
+            }
+            SegmentRouterInfo info = new SegmentRouterInfo();
+            info.nodeSid = ((SegmentRouterConfig) cfg).getNodeSid();
+            info.deviceId = ((SegmentRouterConfig) cfg).getDpid();
+            info.mac = MacAddress.valueOf(((
+                    SegmentRouterConfig) cfg).getRouterMac());
+            String routerIp = ((SegmentRouterConfig) cfg).getRouterIp();
+            Ip4Prefix prefix = checkNotNull(IpPrefix.valueOf(routerIp).getIp4Prefix());
+            info.ip = prefix.address();
+            info.isEdge = ((SegmentRouterConfig) cfg).isEdgeRouter();
+            info.subnets = new HashMap<>();
+            info.gatewayIps = new HashMap<PortNumber, Ip4Address>();
+            for (Subnet s: ((SegmentRouterConfig) cfg).getSubnets()) {
+                info.subnets.put(PortNumber.portNumber(s.getPortNo()),
+                                 Ip4Prefix.valueOf(s.getSubnetIp()));
+                String gatewayIp = s.getSubnetIp().
+                        substring(0, s.getSubnetIp().indexOf('/'));
+                info.gatewayIps.put(PortNumber.portNumber(s.getPortNo()),
+                                    Ip4Address.valueOf(gatewayIp));
+            }
+            info.adjacencySids = ((SegmentRouterConfig) cfg).getAdjacencySids();
+            this.deviceConfigMap.put(info.deviceId, info);
+            this.allSegmentIds.add(info.nodeSid);
+
+        }
+    }
+
+    /**
+     * Returns the segment id of a segment router.
+     *
+     * @param deviceId device identifier
+     * @return segment id
+     */
+    @Override
+    public int getSegmentId(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("getSegmentId for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).nodeSid);
+            return deviceConfigMap.get(deviceId).nodeSid;
+        } else {
+            log.warn("getSegmentId for device {} "
+                    + "throwing IllegalStateException "
+                    + "because device does not exist in config", deviceId);
+            throw new IllegalStateException();
+        }
+    }
+
+    /**
+     * Returns the segment id of a segment router given its mac address.
+     *
+     * @param routerMac router mac address
+     * @return segment id
+     */
+    public int getSegmentId(MacAddress routerMac) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+                    deviceConfigMap.entrySet()) {
+            if (entry.getValue().mac.equals(routerMac)) {
+                return entry.getValue().nodeSid;
+            }
+        }
+
+        return -1;
+    }
+
+    /**
+     * Returns the segment id of a segment router given its router ip address.
+     *
+     * @param routerAddress router ip address
+     * @return segment id
+     */
+    public int getSegmentId(Ip4Address routerAddress) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+            deviceConfigMap.entrySet()) {
+            if (entry.getValue().ip.equals(routerAddress)) {
+                return entry.getValue().nodeSid;
+            }
+        }
+
+        return -1;
+    }
+
+    /**
+     * Returns the router mac of a segment router.
+     *
+     * @param deviceId device identifier
+     * @return router mac address
+     */
+    @Override
+    public MacAddress getDeviceMac(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("getDeviceMac for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).mac);
+            return deviceConfigMap.get(deviceId).mac;
+        } else {
+            log.warn("getDeviceMac for device {} "
+                    + "throwing IllegalStateException "
+                    + "because device does not exist in config", deviceId);
+            throw new IllegalStateException();
+        }
+    }
+
+    /**
+     * Returns the router ip address of a segment router.
+     *
+     * @param deviceId device identifier
+     * @return router ip address
+     */
+    public Ip4Address getRouterIp(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("getDeviceIp for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).ip);
+            return deviceConfigMap.get(deviceId).ip;
+        } else {
+            log.warn("getRouterIp for device {} "
+                    + "throwing IllegalStateException "
+                    + "because device does not exist in config", deviceId);
+            throw new IllegalStateException();
+        }
+    }
+
+    /**
+     * Indicates if the segment router is a edge router or
+     * a transit/back bone router.
+     *
+     * @param deviceId device identifier
+     * @return boolean
+     */
+    @Override
+    public boolean isEdgeDevice(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("isEdgeDevice for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).isEdge);
+            return deviceConfigMap.get(deviceId).isEdge;
+        } else {
+            log.warn("isEdgeDevice for device {} "
+                    + "throwing IllegalStateException "
+                    + "because device does not exist in config", deviceId);
+            throw new IllegalStateException();
+        }
+    }
+
+    /**
+     * Returns the segment ids of all configured segment routers.
+     *
+     * @return list of segment ids
+     */
+    @Override
+    public List<Integer> getAllDeviceSegmentIds() {
+        return allSegmentIds;
+    }
+
+    /**
+     * Returns the device identifier or data plane identifier (dpid)
+     * of a segment router given its segment id.
+     *
+     * @param sid segment id
+     * @return deviceId device identifier
+     */
+    public DeviceId getDeviceId(int sid) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+            deviceConfigMap.entrySet()) {
+            if (entry.getValue().nodeSid == sid) {
+                return entry.getValue().deviceId;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Returns the device identifier or data plane identifier (dpid)
+     * of a segment router given its router ip address.
+     *
+     * @param ipAddress router ip address
+     * @return deviceId device identifier
+     */
+    public DeviceId getDeviceId(Ip4Address ipAddress) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+            deviceConfigMap.entrySet()) {
+            if (entry.getValue().ip.equals(ipAddress)) {
+                return entry.getValue().deviceId;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Returns the configured subnet gateway ip addresses for a segment router.
+     *
+     * @param deviceId device identifier
+     * @return list of ip addresses
+     */
+    public List<Ip4Address> getSubnetGatewayIps(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("getSubnetGatewayIps for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).gatewayIps.values());
+            return new ArrayList<Ip4Address>(deviceConfigMap.
+                    get(deviceId).gatewayIps.values());
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Returns the configured subnet prefixes for a segment router.
+     *
+     * @param deviceId device identifier
+     * @return list of ip prefixes
+     */
+    public List<Ip4Prefix> getSubnets(DeviceId deviceId) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            log.debug("getSubnets for device{} is {}",
+                    deviceId,
+                    deviceConfigMap.get(deviceId).subnets.values());
+            return new ArrayList<Ip4Prefix>(deviceConfigMap.
+                    get(deviceId).subnets.values());
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Returns the router ip address of segment router that has the
+     * specified ip address in its subnets.
+     *
+     * @param destIpAddress target ip address
+     * @return router ip address
+     */
+    public Ip4Address getRouterIpAddressForASubnetHost(Ip4Address destIpAddress) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+                    deviceConfigMap.entrySet()) {
+            for (Ip4Prefix prefix:entry.getValue().subnets.values()) {
+                if (prefix.contains(destIpAddress)) {
+                    return entry.getValue().ip;
+                }
+            }
+        }
+
+        log.debug("No router was found for {}", destIpAddress);
+        return null;
+    }
+
+    /**
+     * Returns the router mac address of segment router that has the
+     * specified ip address as one of its subnet gateway ip address.
+     *
+     * @param gatewayIpAddress router gateway ip address
+     * @return router mac address
+     */
+    public MacAddress getRouterMacForAGatewayIp(Ip4Address gatewayIpAddress) {
+        for (Map.Entry<DeviceId, SegmentRouterInfo> entry:
+                deviceConfigMap.entrySet()) {
+            if (entry.getValue().gatewayIps.
+                    values().contains(gatewayIpAddress)) {
+                return entry.getValue().mac;
+            }
+        }
+
+        log.debug("Cannot find a router for {}", gatewayIpAddress);
+        return null;
+    }
+
+
+    /**
+     * Checks if the host is in the subnet defined in the router with the
+     * device ID given.
+     *
+     * @param deviceId device identification of the router
+     * @param hostIp   host IP address to check
+     * @return true if the host is within the subnet of the router,
+     * false if no subnet is defined under the router or if the host is not
+     * within the subnet defined in the router
+     */
+    public boolean inSameSubnet(DeviceId deviceId, Ip4Address hostIp) {
+
+        List<Ip4Prefix> subnets = getSubnets(deviceId);
+        if (subnets == null) {
+            return false;
+        }
+
+        for (Ip4Prefix subnet: subnets) {
+            if (subnet.contains(hostIp)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Returns the ports corresponding to the adjacency Sid given.
+     *
+     * @param deviceId device identification of the router
+     * @param sid adjacency Sid
+     * @return list of port numbers
+     */
+    public List<Integer> getPortsForAdjacencySid(DeviceId deviceId, int sid) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            for (SegmentRouterConfig.AdjacencySid asid : deviceConfigMap.get(deviceId).adjacencySids) {
+                if (asid.getAdjSid() == sid) {
+                    return asid.getPorts();
+                }
+            }
+        }
+
+        return Lists.newArrayList();
+    }
+
+    /**
+     * Check if the Sid given is whether adjacency Sid of the router device or not.
+     *
+     * @param deviceId device identification of the router
+     * @param sid Sid to check
+     * @return true if the Sid given is the adjacency Sid of the device,
+     * otherwise false
+     */
+    public boolean isAdjacencySid(DeviceId deviceId, int sid) {
+        if (deviceConfigMap.get(deviceId) != null) {
+            if (deviceConfigMap.get(deviceId).adjacencySids.isEmpty()) {
+                return false;
+            } else {
+                for (SegmentRouterConfig.AdjacencySid asid:
+                        deviceConfigMap.get(deviceId).adjacencySids) {
+                    if (asid.getAdjSid() == sid) {
+                        return true;
+                    }
+                }
+                return false;
+            }
+        }
+
+        return false;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ECMPShortestPathGraph.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ECMPShortestPathGraph.java
new file mode 100644
index 00000000..cd28fcf9
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/ECMPShortestPathGraph.java
@@ -0,0 +1,374 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onosproject.net.DefaultLink;
+import org.onosproject.net.DefaultPath;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.Path;
+import org.onosproject.net.provider.ProviderId;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * This class creates bandwidth constrained breadth first tree and returns paths
+ * from root Device to leaf Devicees which satisfies the bandwidth condition. If
+ * bandwidth parameter is not specified, the normal breadth first tree will be
+ * calculated. The paths are snapshot paths at the point of the class
+ * instantiation.
+ */
+public class ECMPShortestPathGraph {
+    LinkedList<DeviceId> deviceQueue = new LinkedList<>();
+    LinkedList<Integer> distanceQueue = new LinkedList<>();
+    HashMap<DeviceId, Integer> deviceSearched = new HashMap<>();
+    HashMap<DeviceId, ArrayList<Link>> upstreamLinks = new HashMap<>();
+    HashMap<DeviceId, ArrayList<Path>> paths = new HashMap<>();
+    HashMap<Integer, ArrayList<DeviceId>> distanceDeviceMap = new HashMap<>();
+    DeviceId rootDevice;
+    private SegmentRoutingManager srManager;
+    private static final Logger log = LoggerFactory
+            .getLogger(ECMPShortestPathGraph.class);
+
+    /**
+     * Constructor.
+     *
+     * @param rootDevice root of the BFS tree
+     * @param linkListToAvoid link list to avoid
+     * @param deviceIdListToAvoid device list to avoid
+     */
+    public ECMPShortestPathGraph(DeviceId rootDevice, List<String> deviceIdListToAvoid,
+                                 List<Link> linkListToAvoid) {
+        this.rootDevice = rootDevice;
+        calcECMPShortestPathGraph(deviceIdListToAvoid, linkListToAvoid);
+    }
+
+    /**
+     * Constructor.
+     *
+     * @param rootDevice root of the BFS tree
+     * @param srManager SegmentRoutingManager object
+     */
+    public ECMPShortestPathGraph(DeviceId rootDevice, SegmentRoutingManager srManager) {
+        this.rootDevice = rootDevice;
+        this.srManager = srManager;
+        calcECMPShortestPathGraph();
+    }
+
+    /**
+     * Calculates the BFS tree using any provided constraints and Intents.
+     */
+    private void calcECMPShortestPathGraph() {
+        deviceQueue.add(rootDevice);
+        int currDistance = 0;
+        distanceQueue.add(currDistance);
+        deviceSearched.put(rootDevice, currDistance);
+        while (!deviceQueue.isEmpty()) {
+            DeviceId sw = deviceQueue.poll();
+            DeviceId prevSw = null;
+            currDistance = distanceQueue.poll();
+
+            for (Link link : srManager.linkService.getDeviceEgressLinks(sw)) {
+                DeviceId reachedDevice = link.dst().deviceId();
+                if ((prevSw != null)
+                        && (prevSw.equals(reachedDevice))) {
+                    /* Ignore LAG links between the same set of Devicees */
+                    continue;
+                } else  {
+                    prevSw = reachedDevice;
+                }
+
+                Integer distance = deviceSearched.get(reachedDevice);
+                if ((distance != null) && (distance.intValue() < (currDistance + 1))) {
+                    continue;
+                }
+                if (distance == null) {
+                    /* First time visiting this Device node */
+                    deviceQueue.add(reachedDevice);
+                    distanceQueue.add(currDistance + 1);
+                    deviceSearched.put(reachedDevice, currDistance + 1);
+
+                    ArrayList<DeviceId> distanceSwArray = distanceDeviceMap
+                            .get(currDistance + 1);
+                    if (distanceSwArray == null) {
+                        distanceSwArray = new ArrayList<DeviceId>();
+                        distanceSwArray.add(reachedDevice);
+                        distanceDeviceMap.put(currDistance + 1, distanceSwArray);
+                    } else {
+                        distanceSwArray.add(reachedDevice);
+                    }
+                }
+
+                ArrayList<Link> upstreamLinkArray =
+                        upstreamLinks.get(reachedDevice);
+                if (upstreamLinkArray == null) {
+                    upstreamLinkArray = new ArrayList<Link>();
+                    upstreamLinkArray.add(copyDefaultLink(link));
+                    //upstreamLinkArray.add(link);
+                    upstreamLinks.put(reachedDevice, upstreamLinkArray);
+                } else {
+                    /* ECMP links */
+                    upstreamLinkArray.add(copyDefaultLink(link));
+                }
+            }
+        }
+    }
+
+    /**
+     * Calculates the BFS tree using any provided constraints and Intents.
+     */
+    private void calcECMPShortestPathGraph(List<String> deviceIdListToAvoid, List<Link> linksToAvoid) {
+        deviceQueue.add(rootDevice);
+        int currDistance = 0;
+        distanceQueue.add(currDistance);
+        deviceSearched.put(rootDevice, currDistance);
+        boolean foundLinkToAvoid = false;
+        while (!deviceQueue.isEmpty()) {
+            DeviceId sw = deviceQueue.poll();
+            DeviceId prevSw = null;
+            currDistance = distanceQueue.poll();
+            for (Link link : srManager.linkService.getDeviceEgressLinks(sw)) {
+                for (Link linkToAvoid: linksToAvoid) {
+                    // TODO: equls should work
+                    //if (link.equals(linkToAvoid)) {
+                    if (linkContains(link, linksToAvoid)) {
+                        foundLinkToAvoid = true;
+                        break;
+                    }
+                }
+                if (foundLinkToAvoid) {
+                    foundLinkToAvoid = false;
+                    continue;
+                }
+                DeviceId reachedDevice = link.dst().deviceId();
+                if (deviceIdListToAvoid.contains(reachedDevice.toString())) {
+                    continue;
+                }
+                if ((prevSw != null)
+                        && (prevSw.equals(reachedDevice))) {
+                    /* Ignore LAG links between the same set of Devicees */
+                    continue;
+                } else {
+                    prevSw = reachedDevice;
+                }
+
+                Integer distance = deviceSearched.get(reachedDevice);
+                if ((distance != null) && (distance.intValue() < (currDistance + 1))) {
+                    continue;
+                }
+                if (distance == null) {
+                    /* First time visiting this Device node */
+                    deviceQueue.add(reachedDevice);
+                    distanceQueue.add(currDistance + 1);
+                    deviceSearched.put(reachedDevice, currDistance + 1);
+
+                    ArrayList<DeviceId> distanceSwArray = distanceDeviceMap
+                            .get(currDistance + 1);
+                    if (distanceSwArray == null) {
+                        distanceSwArray = new ArrayList<DeviceId>();
+                        distanceSwArray.add(reachedDevice);
+                        distanceDeviceMap.put(currDistance + 1, distanceSwArray);
+                    } else {
+                        distanceSwArray.add(reachedDevice);
+                    }
+                }
+
+                ArrayList<Link> upstreamLinkArray =
+                        upstreamLinks.get(reachedDevice);
+                if (upstreamLinkArray == null) {
+                    upstreamLinkArray = new ArrayList<Link>();
+                    upstreamLinkArray.add(copyDefaultLink(link));
+                    upstreamLinks.put(reachedDevice, upstreamLinkArray);
+                } else {
+                    /* ECMP links */
+                    upstreamLinkArray.add(copyDefaultLink(link));
+                }
+            }
+        }
+    }
+
+
+    private boolean linkContains(Link link, List<Link> links) {
+
+        DeviceId srcDevice1 = link.src().deviceId();
+        DeviceId dstDevice1 = link.dst().deviceId();
+        long srcPort1 = link.src().port().toLong();
+        long dstPort1 = link.dst().port().toLong();
+
+        for (Link link2: links) {
+            DeviceId srcDevice2 = link2.src().deviceId();
+            DeviceId dstDevice2 = link2.dst().deviceId();
+            long srcPort2 = link2.src().port().toLong();
+            long dstPort2 = link2.dst().port().toLong();
+
+            if (srcDevice1.toString().equals(srcDevice2.toString())
+                    && dstDevice1.toString().equals(dstDevice2.toString())
+                    && srcPort1 == srcPort2 && dstPort1 == dstPort2) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    private void getDFSPaths(DeviceId dstDeviceDeviceId, Path path, ArrayList<Path> paths) {
+        DeviceId rootDeviceDeviceId = rootDevice;
+        for (Link upstreamLink : upstreamLinks.get(dstDeviceDeviceId)) {
+            /* Deep clone the path object */
+            Path sofarPath;
+            ArrayList<Link> sofarLinks = new ArrayList<Link>();
+            if (path != null && !path.links().isEmpty()) {
+                sofarLinks.addAll(path.links());
+            }
+            sofarLinks.add(upstreamLink);
+            sofarPath = new DefaultPath(ProviderId.NONE, sofarLinks, 0);
+            if (upstreamLink.src().deviceId().equals(rootDeviceDeviceId)) {
+                paths.add(sofarPath);
+                return;
+            } else {
+                getDFSPaths(upstreamLink.src().deviceId(), sofarPath, paths);
+            }
+        }
+    }
+
+    /**
+     * Return root Device for the graph.
+     *
+     * @return root Device
+     */
+    public DeviceId getRootDevice() {
+        return rootDevice;
+    }
+
+    /**
+     * Return the computed ECMP paths from the root Device to a given Device in
+     * the network.
+     *
+     * @param targetDevice the target Device
+     * @return the list of ECMP Paths from the root Device to the target Device
+     */
+    public ArrayList<Path> getECMPPaths(DeviceId targetDevice) {
+        ArrayList<Path> pathArray = paths.get(targetDevice);
+        if (pathArray == null && deviceSearched.containsKey(
+                targetDevice)) {
+            pathArray = new ArrayList<>();
+            DeviceId sw = targetDevice;
+            getDFSPaths(sw, null, pathArray);
+            paths.put(targetDevice, pathArray);
+        }
+        return pathArray;
+    }
+
+    /**
+     * Return the complete info of the computed ECMP paths for each Device
+     * learned in multiple iterations from the root Device.
+     *
+     * @return the hash table of Devicees learned in multiple Dijkstra
+     *         iterations and corresponding ECMP paths to it from the root
+     *         Device
+     */
+    public HashMap<Integer, HashMap<DeviceId,
+            ArrayList<Path>>> getCompleteLearnedDeviceesAndPaths() {
+
+        HashMap<Integer, HashMap<DeviceId, ArrayList<Path>>> pathGraph = new
+                HashMap<Integer, HashMap<DeviceId, ArrayList<Path>>>();
+
+        for (Integer itrIndx : distanceDeviceMap.keySet()) {
+            HashMap<DeviceId, ArrayList<Path>> swMap = new
+                    HashMap<DeviceId, ArrayList<Path>>();
+            for (DeviceId sw : distanceDeviceMap.get(itrIndx)) {
+                swMap.put(sw, getECMPPaths(sw));
+            }
+            pathGraph.put(itrIndx, swMap);
+        }
+
+        return pathGraph;
+    }
+
+    /**
+     * Return the complete info of the computed ECMP paths for each Device
+     * learned in multiple iterations from the root Device.
+     *
+     * @return the hash table of Devicees learned in multiple Dijkstra
+     *         iterations and corresponding ECMP paths in terms of Devicees to
+     *         be traversed to it from the root Device
+     */
+    public HashMap<Integer, HashMap<DeviceId,
+            ArrayList<ArrayList<DeviceId>>>> getAllLearnedSwitchesAndVia() {
+
+        HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>> deviceViaMap =
+                new HashMap<Integer, HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>>();
+
+        for (Integer itrIndx : distanceDeviceMap.keySet()) {
+            HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>> swMap =
+                    new HashMap<DeviceId, ArrayList<ArrayList<DeviceId>>>();
+
+            for (DeviceId sw : distanceDeviceMap.get(itrIndx)) {
+                ArrayList<ArrayList<DeviceId>> swViaArray = new ArrayList<>();
+                for (Path path : getECMPPaths(sw)) {
+                    ArrayList<DeviceId> swVia = new ArrayList<>();
+                    for (Link link : path.links()) {
+                        if (link.src().deviceId().equals(rootDevice)) {
+                            /* No need to add the root Device again in
+                             * the Via list
+                             */
+                            continue;
+                        }
+                        swVia.add(link.src().deviceId());
+                    }
+                    swViaArray.add(swVia);
+                }
+                swMap.put(sw, swViaArray);
+            }
+            deviceViaMap.put(itrIndx, swMap);
+        }
+        return deviceViaMap;
+    }
+
+
+    private Link copyDefaultLink(Link link) {
+        DefaultLink src = (DefaultLink) link;
+        DefaultLink defaultLink = new DefaultLink(src.providerId(), src.src(),
+                src.dst(), src.type(), src.annotations());
+
+        return defaultLink;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sBuilder = new StringBuilder();
+        for (Device device: srManager.deviceService.getDevices()) {
+            if (device.id() != rootDevice) {
+                sBuilder.append("Paths from" + rootDevice + " to " + device.id() + "\r\n");
+                ArrayList<Path> paths = getECMPPaths(device.id());
+                if (paths != null) {
+                    for (Path path : paths) {
+                        for (Link link : path.links()) {
+                            sBuilder.append(" : " + link.src() + " -> " + link.dst());
+                        }
+                    }
+                }
+            }
+        }
+        return sBuilder.toString();
+    }
+}
+
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IcmpHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IcmpHandler.java
new file mode 100644
index 00000000..0f8fa59d
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IcmpHandler.java
@@ -0,0 +1,171 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.ICMP;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.MPLS;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.packet.DefaultOutboundPacket;
+import org.onosproject.net.packet.InboundPacket;
+import org.onosproject.net.packet.OutboundPacket;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.ByteBuffer;
+import java.util.List;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class IcmpHandler {
+
+    private static Logger log = LoggerFactory.getLogger(IcmpHandler.class);
+    private SegmentRoutingManager srManager;
+    private DeviceConfiguration config;
+
+    /**
+     * Creates an IcmpHandler object.
+     *
+     * @param srManager SegmentRoutingManager object
+     */
+    public IcmpHandler(SegmentRoutingManager srManager) {
+        this.srManager = srManager;
+        this.config = checkNotNull(srManager.deviceConfiguration);
+    }
+
+    /**
+     * Process incoming ICMP packet.
+     * If it is an ICMP request to router or known host, then sends an ICMP response.
+     * If it is an ICMP packet to known host and forward the packet to the host.
+     * If it is an ICMP packet to unknown host in a subnet, then sends an ARP request
+     * to the subnet.
+     *
+     * @param pkt inbound packet
+     */
+    public void processPacketIn(InboundPacket pkt) {
+
+        Ethernet ethernet = pkt.parsed();
+        IPv4 ipv4 = (IPv4) ethernet.getPayload();
+
+        ConnectPoint connectPoint = pkt.receivedFrom();
+        DeviceId deviceId = connectPoint.deviceId();
+        Ip4Address destinationAddress =
+                Ip4Address.valueOf(ipv4.getDestinationAddress());
+        List<Ip4Address> gatewayIpAddresses = config.getSubnetGatewayIps(deviceId);
+        Ip4Address routerIp = config.getRouterIp(deviceId);
+        IpPrefix routerIpPrefix = IpPrefix.valueOf(routerIp, IpPrefix.MAX_INET_MASK_LENGTH);
+        Ip4Address routerIpAddress = routerIpPrefix.getIp4Prefix().address();
+
+        // ICMP to the router IP or gateway IP
+        if (((ICMP) ipv4.getPayload()).getIcmpType() == ICMP.TYPE_ECHO_REQUEST &&
+                (destinationAddress.equals(routerIpAddress) ||
+                        gatewayIpAddresses.contains(destinationAddress))) {
+            sendICMPResponse(ethernet, connectPoint);
+            // TODO: do we need to set the flow rule again ??
+
+        // ICMP for any known host
+        } else if (!srManager.hostService.getHostsByIp(destinationAddress).isEmpty()) {
+            srManager.ipHandler.forwardPackets(deviceId, destinationAddress);
+
+        // ICMP for an unknown host in the subnet of the router
+        } else if (config.inSameSubnet(deviceId, destinationAddress)) {
+            srManager.arpHandler.sendArpRequest(deviceId, destinationAddress, connectPoint);
+
+        // ICMP for an unknown host
+        } else {
+            log.debug("ICMP request for unknown host {} ", destinationAddress);
+            // Do nothing
+        }
+    }
+
+    private void sendICMPResponse(Ethernet icmpRequest, ConnectPoint outport) {
+
+        Ethernet icmpReplyEth = new Ethernet();
+
+        IPv4 icmpRequestIpv4 = (IPv4) icmpRequest.getPayload();
+        IPv4 icmpReplyIpv4 = new IPv4();
+
+        int destAddress = icmpRequestIpv4.getDestinationAddress();
+        icmpReplyIpv4.setDestinationAddress(icmpRequestIpv4.getSourceAddress());
+        icmpReplyIpv4.setSourceAddress(destAddress);
+        icmpReplyIpv4.setTtl((byte) 64);
+        icmpReplyIpv4.setChecksum((short) 0);
+
+        ICMP icmpReply = new ICMP();
+        icmpReply.setIcmpType(ICMP.TYPE_ECHO_REPLY);
+        icmpReply.setIcmpCode(ICMP.SUBTYPE_ECHO_REPLY);
+        icmpReply.setChecksum((short) 0);
+
+        icmpReplyIpv4.setPayload(icmpReply);
+
+        icmpReplyEth.setPayload(icmpReplyIpv4);
+        icmpReplyEth.setEtherType(Ethernet.TYPE_IPV4);
+        icmpReplyEth.setDestinationMACAddress(icmpRequest.getSourceMACAddress());
+        icmpReplyEth.setSourceMACAddress(icmpRequest.getDestinationMACAddress());
+        icmpReplyEth.setVlanID(icmpRequest.getVlanID());
+
+        Ip4Address destIpAddress = Ip4Address.valueOf(icmpReplyIpv4.getDestinationAddress());
+        Ip4Address destRouterAddress = config.getRouterIpAddressForASubnetHost(destIpAddress);
+        int sid = config.getSegmentId(destRouterAddress);
+        if (sid < 0) {
+            log.warn("Cannot find the Segment ID for {}", destAddress);
+            return;
+        }
+
+        sendPacketOut(outport, icmpReplyEth, sid);
+
+    }
+
+    private void sendPacketOut(ConnectPoint outport, Ethernet payload, int sid) {
+
+        IPv4 ipPacket = (IPv4) payload.getPayload();
+        Ip4Address destIpAddress = Ip4Address.valueOf(ipPacket.getDestinationAddress());
+
+        if (sid == -1 || config.getSegmentId(payload.getDestinationMAC()) == sid ||
+                config.inSameSubnet(outport.deviceId(), destIpAddress)) {
+            TrafficTreatment treatment = DefaultTrafficTreatment.builder().
+                    setOutput(outport.port()).build();
+            OutboundPacket packet = new DefaultOutboundPacket(outport.deviceId(),
+                    treatment, ByteBuffer.wrap(payload.serialize()));
+            srManager.packetService.emit(packet);
+        } else {
+            log.warn("Send a MPLS packet as a ICMP response");
+            TrafficTreatment treatment = DefaultTrafficTreatment.builder()
+                    .setOutput(outport.port())
+                    .build();
+
+            payload.setEtherType(Ethernet.MPLS_UNICAST);
+            MPLS mplsPkt = new MPLS();
+            mplsPkt.setLabel(sid);
+            mplsPkt.setTtl(((IPv4) payload.getPayload()).getTtl());
+            mplsPkt.setPayload(payload.getPayload());
+            payload.setPayload(mplsPkt);
+
+            OutboundPacket packet = new DefaultOutboundPacket(outport.deviceId(),
+                    treatment, ByteBuffer.wrap(payload.serialize()));
+
+            srManager.packetService.emit(packet);
+        }
+    }
+
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IpHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IpHandler.java
new file mode 100644
index 00000000..81d00f50
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/IpHandler.java
@@ -0,0 +1,152 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.Ip4Address;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Host;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.packet.DefaultOutboundPacket;
+import org.onosproject.net.packet.InboundPacket;
+import org.onosproject.net.packet.OutboundPacket;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.nio.ByteBuffer;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class IpHandler {
+
+    private static Logger log = LoggerFactory.getLogger(IpHandler.class);
+    private SegmentRoutingManager srManager;
+    private DeviceConfiguration config;
+    private ConcurrentHashMap<Ip4Address, ConcurrentLinkedQueue<IPv4>> ipPacketQueue;
+
+    /**
+     * Creates an IpHandler object.
+     *
+     * @param srManager SegmentRoutingManager object
+     */
+    public IpHandler(SegmentRoutingManager srManager) {
+        this.srManager = srManager;
+        this.config = checkNotNull(srManager.deviceConfiguration);
+        ipPacketQueue = new ConcurrentHashMap<Ip4Address, ConcurrentLinkedQueue<IPv4>>();
+    }
+
+    /**
+     * Processes incoming IP packets.
+     *
+     * If it is an IP packet for known host, then forward it to the host.
+     * If it is an IP packet for unknown host in subnet, then send an ARP request
+     * to the subnet.
+     *
+     * @param pkt incoming packet
+     */
+    public void processPacketIn(InboundPacket pkt) {
+        Ethernet ethernet = pkt.parsed();
+        IPv4 ipv4 = (IPv4) ethernet.getPayload();
+
+        ConnectPoint connectPoint = pkt.receivedFrom();
+        DeviceId deviceId = connectPoint.deviceId();
+        Ip4Address destinationAddress =
+                Ip4Address.valueOf(ipv4.getDestinationAddress());
+
+        // IP packet for know hosts
+        if (!srManager.hostService.getHostsByIp(destinationAddress).isEmpty()) {
+            forwardPackets(deviceId, destinationAddress);
+
+        // IP packet for unknown host in the subnet of the router
+        } else if (config.inSameSubnet(deviceId, destinationAddress)) {
+            srManager.arpHandler.sendArpRequest(deviceId, destinationAddress, connectPoint);
+
+        // IP packets for unknown host
+        } else {
+            log.debug("ICMP request for unknown host {} which is not in the subnet",
+                    destinationAddress);
+            // Do nothing
+        }
+    }
+
+    /**
+     * Adds the IP packet to a buffer.
+     * The packets are forwarded to corresponding destination when the destination
+     * MAC address is known via ARP response.
+     *
+     * @param ipPacket IP packet to add to the buffer
+     */
+    public void addToPacketBuffer(IPv4 ipPacket) {
+
+        // Better not buffer TPC packets due to out-of-order packet transfer
+        if (ipPacket.getProtocol() == IPv4.PROTOCOL_TCP) {
+            return;
+        }
+
+        Ip4Address destIpAddress = Ip4Address.valueOf(ipPacket.getDestinationAddress());
+
+        if (ipPacketQueue.get(destIpAddress) == null) {
+            ConcurrentLinkedQueue<IPv4> queue = new ConcurrentLinkedQueue<IPv4>();
+            queue.add(ipPacket);
+            ipPacketQueue.put(destIpAddress, queue);
+        } else {
+            ipPacketQueue.get(destIpAddress).add(ipPacket);
+        }
+    }
+
+    /**
+     * Forwards IP packets in the buffer to the destination IP address.
+     * It is called when the controller finds the destination MAC address
+     * via ARP responsees.
+     *
+     * @param deviceId switch device ID
+     * @param destIpAddress destination IP address
+     */
+    public void forwardPackets(DeviceId deviceId, Ip4Address destIpAddress) {
+        if (ipPacketQueue.get(destIpAddress) == null) {
+            return;
+        }
+
+        for (IPv4 ipPacket : ipPacketQueue.get(destIpAddress)) {
+            Ip4Address destAddress = Ip4Address.valueOf(ipPacket.getDestinationAddress());
+            if (ipPacket != null && config.inSameSubnet(deviceId, destAddress)) {
+                ipPacket.setTtl((byte) (ipPacket.getTtl() - 1));
+                ipPacket.setChecksum((short) 0);
+                for (Host dest: srManager.hostService.getHostsByIp(destIpAddress)) {
+                    Ethernet eth = new Ethernet();
+                    eth.setDestinationMACAddress(dest.mac());
+                    eth.setSourceMACAddress(config.getDeviceMac(deviceId));
+                    eth.setEtherType(Ethernet.TYPE_IPV4);
+                    eth.setPayload(ipPacket);
+
+                    TrafficTreatment treatment = DefaultTrafficTreatment.builder().
+                            setOutput(dest.location().port()).build();
+                    OutboundPacket packet = new DefaultOutboundPacket(deviceId,
+                            treatment, ByteBuffer.wrap(eth.serialize()));
+                    srManager.packetService.emit(packet);
+                    ipPacketQueue.get(destIpAddress).remove(ipPacket);
+                }
+                ipPacketQueue.get(destIpAddress).remove(ipPacket);
+            }
+        }
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/NetworkConfigHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/NetworkConfigHandler.java
new file mode 100644
index 00000000..d3468178
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/NetworkConfigHandler.java
@@ -0,0 +1,157 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import com.google.common.collect.Lists;
+
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.Ip4Prefix;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.MacAddress;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.PortNumber;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.List;
+import java.util.Set;
+
+/**
+ * This class is temporary class and used only for test.
+ * It will be replaced with "real" Network Config Manager.
+ *
+ * TODO: Knock off this wrapper and directly use DeviceConfiguration class
+ */
+
+public class NetworkConfigHandler {
+
+    private static Logger log = LoggerFactory.getLogger(NetworkConfigHandler.class);
+    private SegmentRoutingManager srManager;
+    private DeviceConfiguration deviceConfig;
+
+    public NetworkConfigHandler(SegmentRoutingManager srManager,
+                                DeviceConfiguration deviceConfig) {
+        this.srManager = srManager;
+        this.deviceConfig = deviceConfig;
+    }
+
+    public List<Ip4Address> getGatewayIpAddress(DeviceId deviceId) {
+        return this.deviceConfig.getSubnetGatewayIps(deviceId);
+    }
+
+    public IpPrefix getRouterIpAddress(DeviceId deviceId) {
+        return IpPrefix.valueOf(deviceConfig.getRouterIp(deviceId), 32);
+    }
+
+    public MacAddress getRouterMacAddress(DeviceId deviceId) {
+        return deviceConfig.getDeviceMac(deviceId);
+    }
+
+    public boolean inSameSubnet(DeviceId deviceId, Ip4Address destIp) {
+
+        List<Ip4Prefix> subnets = getSubnetInfo(deviceId);
+        if (subnets == null) {
+            return false;
+        }
+
+        return subnets.stream()
+               .anyMatch((subnet) -> subnet.contains(destIp));
+    }
+
+    public boolean inSameSubnet(Ip4Address address, int sid) {
+        DeviceId deviceId = deviceConfig.getDeviceId(sid);
+        if (deviceId == null) {
+            log.warn("Cannot find a device for SID {}", sid);
+            return false;
+        }
+
+        return inSameSubnet(deviceId, address);
+    }
+
+    public List<Ip4Prefix> getSubnetInfo(DeviceId deviceId) {
+        return deviceConfig.getSubnets(deviceId);
+    }
+
+    public int getMplsId(DeviceId deviceId) {
+        return deviceConfig.getSegmentId(deviceId);
+    }
+
+    public int getMplsId(MacAddress routerMac) {
+        return deviceConfig.getSegmentId(routerMac);
+    }
+
+    public int getMplsId(Ip4Address routerIpAddress) {
+        return deviceConfig.getSegmentId(routerIpAddress);
+    }
+
+    public boolean isEcmpNotSupportedInTransit(DeviceId deviceId) {
+        //TODO: temporarily changing to true to test with Dell
+        return true;
+    }
+
+    public boolean isTransitRouter(DeviceId deviceId) {
+        return !(deviceConfig.isEdgeDevice(deviceId));
+    }
+
+
+    public boolean isEdgeRouter(DeviceId deviceId) {
+        return deviceConfig.isEdgeDevice(deviceId);
+    }
+
+    private List<PortNumber> getPortsToNeighbors(DeviceId deviceId, List<DeviceId> fwdSws) {
+
+        List<PortNumber> portNumbers = Lists.newArrayList();
+
+        Set<Link> links = srManager.linkService.getDeviceEgressLinks(deviceId);
+        for (Link link: links) {
+            for (DeviceId swId: fwdSws) {
+                if (link.dst().deviceId().equals(swId)) {
+                    portNumbers.add(link.src().port());
+                    break;
+                }
+            }
+        }
+
+        return portNumbers;
+    }
+
+    public List<PortNumber> getPortsToDevice(DeviceId deviceId) {
+        List<PortNumber> portNumbers = Lists.newArrayList();
+
+        Set<Link> links = srManager.linkService.getDeviceEgressLinks(deviceId);
+        for (Link link: links) {
+            if (link.dst().deviceId().equals(deviceId)) {
+                portNumbers.add(link.src().port());
+            }
+        }
+
+        return portNumbers;
+    }
+
+
+    public Ip4Address getDestinationRouterAddress(Ip4Address destIpAddress) {
+        return deviceConfig.getRouterIpAddressForASubnetHost(destIpAddress);
+    }
+
+    public DeviceId getDeviceId(Ip4Address ip4Address) {
+        return deviceConfig.getDeviceId(ip4Address);
+    }
+
+    public MacAddress getRouterMac(Ip4Address targetAddress) {
+        return deviceConfig.getRouterMacForAGatewayIp(targetAddress);
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Policy.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Policy.java
new file mode 100644
index 00000000..2e417959
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Policy.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+/**
+ * Interface for Segment Routing Policy.
+ */
+public interface Policy {
+    /**
+     * Enums for policy type.
+     */
+    enum Type {
+        // Tunnel flow policy type
+        TUNNEL_FLOW,
+
+        // Load balancing policy type
+        LOADBALANCE,
+
+        // policy to avoid specific routers or links
+        AVOID,
+
+        // Access Control policy type
+        DENY
+    }
+
+    /**
+     * Returns the policy ID.
+     *
+     * @return policy ID
+     */
+    String id();
+
+    /**
+     * Returns the priority of the policy.
+     *
+     * @return priority
+     */
+    int priority();
+
+    /**
+     * Returns the policy type.
+     *
+     * @return policy type
+     */
+    Type type();
+
+    /**
+     * Returns the source IP address of the policy.
+     *
+     * @return source IP address
+     */
+    String srcIp();
+
+    /**
+     * Returns the destination IP address of the policy.
+     *
+     * @return destination IP address
+     */
+    String dstIp();
+
+    /**
+     * Returns the IP protocol of the policy.
+     *
+     * @return IP protocol
+     */
+    String ipProto();
+
+    /**
+     * Returns the source port of the policy.
+     *
+     * @return source port
+     */
+    short srcPort();
+
+    /**
+     * Returns the destination of the policy.
+     *
+     * @return destination port
+     */
+    short dstPort();
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/PolicyHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/PolicyHandler.java
new file mode 100644
index 00000000..83cb7e86
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/PolicyHandler.java
@@ -0,0 +1,215 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.TpPort;
+import org.onosproject.cli.net.IpProtocol;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flowobjective.DefaultForwardingObjective;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.flowobjective.ForwardingObjective;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.slf4j.Logger;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Segment Routing Policy Handler.
+ */
+public class PolicyHandler {
+
+    protected final Logger log = getLogger(getClass());
+
+    private ApplicationId appId;
+    private DeviceConfiguration deviceConfiguration;
+    private FlowObjectiveService flowObjectiveService;
+    private TunnelHandler tunnelHandler;
+    private final EventuallyConsistentMap<String, Policy> policyStore;
+
+    public enum Result {
+        SUCCESS,
+        POLICY_EXISTS,
+        ID_EXISTS,
+        TUNNEL_NOT_FOUND,
+        POLICY_NOT_FOUND,
+        UNSUPPORTED_TYPE
+    }
+
+    /**
+     * Creates a reference.
+     *
+     * @param appId                segment routing application ID
+     * @param deviceConfiguration  DeviceConfiguration reference
+     * @param flowObjectiveService FlowObjectiveService reference
+     * @param tunnelHandler        tunnel handler reference
+     * @param policyStore          policy store
+     */
+    public PolicyHandler(ApplicationId appId,
+                         DeviceConfiguration deviceConfiguration,
+                         FlowObjectiveService flowObjectiveService,
+                         TunnelHandler tunnelHandler,
+                         EventuallyConsistentMap<String, Policy> policyStore) {
+        this.appId = appId;
+        this.deviceConfiguration = deviceConfiguration;
+        this.flowObjectiveService = flowObjectiveService;
+        this.tunnelHandler = tunnelHandler;
+        this.policyStore = policyStore;
+    }
+
+    /**
+     * Returns the policies.
+     *
+     * @return policy list
+     */
+    public List<Policy> getPolicies() {
+        return policyStore.values()
+                .stream()
+                .filter(policy -> policy instanceof TunnelPolicy)
+                .map(policy -> new TunnelPolicy((TunnelPolicy) policy))
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * Creates a policy using the policy information given.
+     *  @param policy policy reference to create
+     *  @return ID_EXISTS if the same policy ID exists,
+     *  POLICY_EXISTS if the same policy exists, TUNNEL_NOT_FOUND if the tunnel
+     *  does not exists, UNSUPPORTED_TYPE if the policy type is not supported,
+     *  SUCCESS if the policy is created successfully
+     */
+    public Result createPolicy(Policy policy) {
+
+        if (policyStore.containsKey(policy.id())) {
+            log.warn("The policy id {} exists already", policy.id());
+            return Result.ID_EXISTS;
+        }
+
+        if (policyStore.containsValue(policy)) {
+            log.warn("The same policy exists already");
+            return Result.POLICY_EXISTS;
+        }
+
+        if (policy.type() == Policy.Type.TUNNEL_FLOW) {
+
+            TunnelPolicy tunnelPolicy = (TunnelPolicy) policy;
+            Tunnel tunnel = tunnelHandler.getTunnel(tunnelPolicy.tunnelId());
+            if (tunnel == null) {
+                return Result.TUNNEL_NOT_FOUND;
+            }
+
+            ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective
+                    .builder()
+                    .fromApp(appId)
+                    .makePermanent()
+                    .nextStep(tunnel.groupId())
+                    .withPriority(tunnelPolicy.priority())
+                    .withSelector(buildSelector(policy))
+                    .withFlag(ForwardingObjective.Flag.VERSATILE);
+
+            DeviceId source = deviceConfiguration.getDeviceId(tunnel.labelIds().get(0));
+            flowObjectiveService.forward(source, fwdBuilder.add());
+
+        } else {
+            log.warn("Policy type {} is not supported yet.", policy.type());
+            return Result.UNSUPPORTED_TYPE;
+        }
+
+        policyStore.put(policy.id(), policy);
+
+        return Result.SUCCESS;
+    }
+
+    /**
+     * Removes the policy given.
+     *
+     * @param policyInfo policy information to remove
+     * @return POLICY_NOT_FOUND if the policy to remove does not exists,
+     * SUCCESS if it is removed successfully
+     */
+    public Result removePolicy(Policy policyInfo) {
+
+        if (policyStore.get(policyInfo.id()) != null) {
+            Policy policy = policyStore.get(policyInfo.id());
+            if (policy.type() == Policy.Type.TUNNEL_FLOW) {
+                TunnelPolicy tunnelPolicy = (TunnelPolicy) policy;
+                Tunnel tunnel = tunnelHandler.getTunnel(tunnelPolicy.tunnelId());
+
+                ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective
+                        .builder()
+                        .fromApp(appId)
+                        .makePermanent()
+                        .withSelector(buildSelector(policy))
+                        .withPriority(tunnelPolicy.priority())
+                        .nextStep(tunnel.groupId())
+                        .withFlag(ForwardingObjective.Flag.VERSATILE);
+
+                DeviceId source = deviceConfiguration.getDeviceId(tunnel.labelIds().get(0));
+                flowObjectiveService.forward(source, fwdBuilder.remove());
+
+                policyStore.remove(policyInfo.id());
+            }
+        } else {
+            log.warn("Policy {} was not found", policyInfo.id());
+            return Result.POLICY_NOT_FOUND;
+        }
+
+        return Result.SUCCESS;
+    }
+
+
+    private TrafficSelector buildSelector(Policy policy) {
+
+        TrafficSelector.Builder tsb = DefaultTrafficSelector.builder();
+        tsb.matchEthType(Ethernet.TYPE_IPV4);
+        if (policy.dstIp() != null && !policy.dstIp().isEmpty()) {
+            tsb.matchIPDst(IpPrefix.valueOf(policy.dstIp()));
+        }
+        if (policy.srcIp() != null && !policy.srcIp().isEmpty()) {
+            tsb.matchIPSrc(IpPrefix.valueOf(policy.srcIp()));
+        }
+        if (policy.ipProto() != null && !policy.ipProto().isEmpty()) {
+            Short ipProto = IpProtocol.valueOf(policy.ipProto()).value();
+            tsb.matchIPProtocol(ipProto.byteValue());
+            if (IpProtocol.valueOf(policy.ipProto()).equals(IpProtocol.TCP)) {
+                if (policy.srcPort() != 0) {
+                    tsb.matchTcpSrc(TpPort.tpPort(policy.srcPort()));
+                }
+                if (policy.dstPort() != 0) {
+                    tsb.matchTcpDst(TpPort.tpPort(policy.dstPort()));
+                }
+            } else if (IpProtocol.valueOf(policy.ipProto()).equals(IpProtocol.UDP)) {
+                if (policy.srcPort() != 0) {
+                    tsb.matchUdpSrc(TpPort.tpPort(policy.srcPort()));
+                }
+                if (policy.dstPort() != 0) {
+                    tsb.matchUdpDst(TpPort.tpPort(policy.dstPort()));
+                }
+            }
+        }
+
+        return tsb.build();
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/RoutingRulePopulator.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/RoutingRulePopulator.java
new file mode 100644
index 00000000..59fc4ca7
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/RoutingRulePopulator.java
@@ -0,0 +1,430 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.Ip4Prefix;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.MacAddress;
+import org.onlab.packet.MplsLabel;
+import org.onlab.packet.VlanId;
+import org.onosproject.segmentrouting.grouphandler.NeighborSet;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flow.criteria.Criteria;
+import org.onosproject.net.flowobjective.DefaultFilteringObjective;
+import org.onosproject.net.flowobjective.DefaultForwardingObjective;
+import org.onosproject.net.flowobjective.FilteringObjective;
+import org.onosproject.net.flowobjective.ForwardingObjective;
+import org.onosproject.net.flowobjective.Objective;
+import org.onosproject.net.flowobjective.ObjectiveError;
+import org.onosproject.net.flowobjective.ForwardingObjective.Builder;
+import org.onosproject.net.flowobjective.ObjectiveContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicLong;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+public class RoutingRulePopulator {
+
+    private static final Logger log = LoggerFactory
+            .getLogger(RoutingRulePopulator.class);
+
+    private AtomicLong rulePopulationCounter;
+    private SegmentRoutingManager srManager;
+    private DeviceConfiguration config;
+    /**
+     * Creates a RoutingRulePopulator object.
+     *
+     * @param srManager segment routing manager reference
+     */
+    public RoutingRulePopulator(SegmentRoutingManager srManager) {
+        this.srManager = srManager;
+        this.config = checkNotNull(srManager.deviceConfiguration);
+        this.rulePopulationCounter = new AtomicLong(0);
+    }
+
+    /**
+     * Resets the population counter.
+     */
+    public void resetCounter() {
+        rulePopulationCounter.set(0);
+    }
+
+    /**
+     * Returns the number of rules populated.
+     *
+     * @return number of rules
+     */
+    public long getCounter() {
+        return rulePopulationCounter.get();
+    }
+
+    /**
+     * Populates IP flow rules for specific hosts directly connected to the
+     * switch.
+     *
+     * @param deviceId switch ID to set the rules
+     * @param hostIp host IP address
+     * @param hostMac host MAC address
+     * @param outPort port where the host is connected
+     */
+    public void populateIpRuleForHost(DeviceId deviceId, Ip4Address hostIp,
+                                      MacAddress hostMac, PortNumber outPort) {
+        TrafficSelector.Builder sbuilder = DefaultTrafficSelector.builder();
+        TrafficTreatment.Builder tbuilder = DefaultTrafficTreatment.builder();
+
+        sbuilder.matchIPDst(IpPrefix.valueOf(hostIp, 32));
+        sbuilder.matchEthType(Ethernet.TYPE_IPV4);
+
+        tbuilder.deferred()
+                .setEthDst(hostMac)
+                .setEthSrc(config.getDeviceMac(deviceId))
+                .setOutput(outPort);
+
+        TrafficTreatment treatment = tbuilder.build();
+        TrafficSelector selector = sbuilder.build();
+
+        ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective
+                .builder().fromApp(srManager.appId).makePermanent()
+                .withSelector(selector).withTreatment(treatment)
+                .withPriority(100).withFlag(ForwardingObjective.Flag.SPECIFIC);
+
+        log.debug("Installing IPv4 forwarding objective "
+                + "for host {} in switch {}", hostIp, deviceId);
+        srManager.flowObjectiveService.
+            forward(deviceId,
+                    fwdBuilder.
+                    add(new SRObjectiveContext(deviceId,
+                                           SRObjectiveContext.ObjectiveType.FORWARDING)));
+        rulePopulationCounter.incrementAndGet();
+    }
+
+    /**
+     * Populates IP flow rules for the subnets of the destination router.
+     *
+     * @param deviceId switch ID to set the rules
+     * @param subnets subnet information
+     * @param destSw destination switch ID
+     * @param nextHops next hop switch ID list
+     * @return true if all rules are set successfully, false otherwise
+     */
+    public boolean populateIpRuleForSubnet(DeviceId deviceId,
+                                           List<Ip4Prefix> subnets,
+                                           DeviceId destSw,
+                                           Set<DeviceId> nextHops) {
+
+        for (IpPrefix subnet : subnets) {
+            if (!populateIpRuleForRouter(deviceId, subnet, destSw, nextHops)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Populates IP flow rules for the router IP address.
+     *
+     * @param deviceId device ID to set the rules
+     * @param ipPrefix the IP address of the destination router
+     * @param destSw device ID of the destination router
+     * @param nextHops next hop switch ID list
+     * @return true if all rules are set successfully, false otherwise
+     */
+    public boolean populateIpRuleForRouter(DeviceId deviceId,
+                                           IpPrefix ipPrefix, DeviceId destSw,
+                                           Set<DeviceId> nextHops) {
+
+        TrafficSelector.Builder sbuilder = DefaultTrafficSelector.builder();
+        TrafficTreatment.Builder tbuilder = DefaultTrafficTreatment.builder();
+
+        sbuilder.matchIPDst(ipPrefix);
+        sbuilder.matchEthType(Ethernet.TYPE_IPV4);
+
+        NeighborSet ns = null;
+
+        // If the next hop is the same as the final destination, then MPLS label
+        // is not set.
+        if (nextHops.size() == 1 && nextHops.toArray()[0].equals(destSw)) {
+            tbuilder.deferred().decNwTtl();
+            ns = new NeighborSet(nextHops);
+        } else {
+            tbuilder.deferred().copyTtlOut();
+            ns = new NeighborSet(nextHops, config.getSegmentId(destSw));
+        }
+
+        TrafficTreatment treatment = tbuilder.build();
+        TrafficSelector selector = sbuilder.build();
+
+        if (srManager.getNextObjectiveId(deviceId, ns) <= 0) {
+            log.warn("No next objective in {} for ns: {}", deviceId, ns);
+            return false;
+        }
+
+        ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective
+                .builder()
+                .fromApp(srManager.appId)
+                .makePermanent()
+                .nextStep(srManager.getNextObjectiveId(deviceId, ns))
+                .withTreatment(treatment)
+                .withSelector(selector)
+                .withPriority(100)
+                .withFlag(ForwardingObjective.Flag.SPECIFIC);
+        log.debug("Installing IPv4 forwarding objective "
+                        + "for router IP/subnet {} in switch {}",
+                ipPrefix,
+                deviceId);
+        srManager.flowObjectiveService.
+            forward(deviceId,
+                    fwdBuilder.
+                    add(new SRObjectiveContext(deviceId,
+                                               SRObjectiveContext.ObjectiveType.FORWARDING)));
+        rulePopulationCounter.incrementAndGet();
+
+        return true;
+    }
+
+    /**
+     * Populates MPLS flow rules to all transit routers.
+     *
+     * @param deviceId device ID of the switch to set the rules
+     * @param destSwId destination switch device ID
+     * @param nextHops next hops switch ID list
+     * @return true if all rules are set successfully, false otherwise
+     */
+    public boolean populateMplsRule(DeviceId deviceId, DeviceId destSwId,
+                                    Set<DeviceId> nextHops) {
+
+        TrafficSelector.Builder sbuilder = DefaultTrafficSelector.builder();
+        List<ForwardingObjective.Builder> fwdObjBuilders = new ArrayList<ForwardingObjective.Builder>();
+
+        // TODO Handle the case of Bos == false
+        sbuilder.matchMplsLabel(MplsLabel.mplsLabel(config.getSegmentId(destSwId)));
+        sbuilder.matchEthType(Ethernet.MPLS_UNICAST);
+
+        // If the next hop is the destination router, do PHP
+        if (nextHops.size() == 1 && destSwId.equals(nextHops.toArray()[0])) {
+            log.debug("populateMplsRule: Installing MPLS forwarding objective for "
+                    + "label {} in switch {} with PHP",
+                    config.getSegmentId(destSwId),
+                    deviceId);
+
+            ForwardingObjective.Builder fwdObjBosBuilder =
+                    getMplsForwardingObjective(deviceId,
+                                               destSwId,
+                                               nextHops,
+                                               true,
+                                               true);
+            // TODO: Check with Sangho on why we need this
+            ForwardingObjective.Builder fwdObjNoBosBuilder =
+                    getMplsForwardingObjective(deviceId,
+                                               destSwId,
+                                               nextHops,
+                                               true,
+                                               false);
+            if (fwdObjBosBuilder != null) {
+                fwdObjBuilders.add(fwdObjBosBuilder);
+            } else {
+                log.warn("Failed to set MPLS rules.");
+                return false;
+            }
+        } else {
+            log.debug("Installing MPLS forwarding objective for "
+                    + "label {} in switch {} without PHP",
+                    config.getSegmentId(destSwId),
+                    deviceId);
+
+            ForwardingObjective.Builder fwdObjBosBuilder =
+                    getMplsForwardingObjective(deviceId,
+                                               destSwId,
+                                               nextHops,
+                                               false,
+                                               true);
+            // TODO: Check with Sangho on why we need this
+            ForwardingObjective.Builder fwdObjNoBosBuilder =
+                    getMplsForwardingObjective(deviceId,
+                                               destSwId,
+                                               nextHops,
+                                               false,
+                                               false);
+            if (fwdObjBosBuilder != null) {
+                fwdObjBuilders.add(fwdObjBosBuilder);
+            } else {
+                log.warn("Failed to set MPLS rules.");
+                return false;
+            }
+        }
+
+        TrafficSelector selector = sbuilder.build();
+        for (ForwardingObjective.Builder fwdObjBuilder : fwdObjBuilders) {
+            ((Builder) ((Builder) fwdObjBuilder.fromApp(srManager.appId)
+                    .makePermanent()).withSelector(selector)
+                    .withPriority(100))
+                    .withFlag(ForwardingObjective.Flag.SPECIFIC);
+            srManager.flowObjectiveService.
+                forward(deviceId,
+                        fwdObjBuilder.
+                        add(new SRObjectiveContext(deviceId,
+                                                   SRObjectiveContext.ObjectiveType.FORWARDING)));
+            rulePopulationCounter.incrementAndGet();
+        }
+
+        return true;
+    }
+
+    private ForwardingObjective.Builder getMplsForwardingObjective(DeviceId deviceId,
+                                                                   DeviceId destSw,
+                                                                   Set<DeviceId> nextHops,
+                                                                   boolean phpRequired,
+                                                                   boolean isBos) {
+
+        ForwardingObjective.Builder fwdBuilder = DefaultForwardingObjective
+                .builder().withFlag(ForwardingObjective.Flag.SPECIFIC);
+
+        TrafficTreatment.Builder tbuilder = DefaultTrafficTreatment.builder();
+
+        if (phpRequired) {
+            log.debug("getMplsForwardingObjective: php required");
+            tbuilder.deferred().copyTtlIn();
+            if (isBos) {
+                tbuilder.deferred().popMpls(Ethernet.TYPE_IPV4).decNwTtl();
+            } else {
+                tbuilder.deferred().popMpls(Ethernet.MPLS_UNICAST).decMplsTtl();
+            }
+        } else {
+            log.debug("getMplsForwardingObjective: php not required");
+            tbuilder.deferred().decMplsTtl();
+        }
+
+        if (!isECMPSupportedInTransitRouter() && !config.isEdgeDevice(deviceId)) {
+            PortNumber port = selectOnePort(deviceId, nextHops);
+            DeviceId nextHop = (DeviceId) nextHops.toArray()[0];
+            if (port == null) {
+                log.warn("No link from {} to {}", deviceId, nextHops);
+                return null;
+            }
+            tbuilder.deferred()
+                    .setEthSrc(config.getDeviceMac(deviceId))
+                    .setEthDst(config.getDeviceMac(nextHop))
+                    .setOutput(port);
+            fwdBuilder.withTreatment(tbuilder.build());
+        } else {
+            NeighborSet ns = new NeighborSet(nextHops);
+            fwdBuilder.withTreatment(tbuilder.build());
+            fwdBuilder.nextStep(srManager
+                    .getNextObjectiveId(deviceId, ns));
+        }
+
+        return fwdBuilder;
+    }
+
+    private boolean isECMPSupportedInTransitRouter() {
+
+        // TODO: remove this function when objectives subsystem is supported.
+        return false;
+    }
+
+    /**
+     * Populates VLAN flows rules. All packets are forwarded to TMAC table.
+     *
+     * @param deviceId switch ID to set the rules
+     */
+    public void populateTableVlan(DeviceId deviceId) {
+        FilteringObjective.Builder fob = DefaultFilteringObjective.builder();
+        fob.withKey(Criteria.matchInPort(PortNumber.ALL))
+                .addCondition(Criteria.matchVlanId(VlanId.NONE));
+        fob.permit().fromApp(srManager.appId);
+        log.debug("populateTableVlan: Installing filtering objective for untagged packets");
+        srManager.flowObjectiveService.
+            filter(deviceId,
+                   fob.add(new SRObjectiveContext(deviceId,
+                                                  SRObjectiveContext.ObjectiveType.FILTER)));
+    }
+
+    /**
+     * Populates TMAC table rules. IP packets are forwarded to IP table. MPLS
+     * packets are forwarded to MPLS table.
+     *
+     * @param deviceId switch ID to set the rules
+     */
+    public void populateTableTMac(DeviceId deviceId) {
+
+        FilteringObjective.Builder fob = DefaultFilteringObjective.builder();
+        fob.withKey(Criteria.matchInPort(PortNumber.ALL))
+                .addCondition(Criteria.matchEthDst(config
+                                      .getDeviceMac(deviceId)));
+        fob.permit().fromApp(srManager.appId);
+        log.debug("populateTableVlan: Installing filtering objective for router mac");
+        srManager.flowObjectiveService.
+            filter(deviceId,
+                   fob.add(new SRObjectiveContext(deviceId,
+                                                  SRObjectiveContext.ObjectiveType.FILTER)));
+    }
+
+    private PortNumber selectOnePort(DeviceId srcId, Set<DeviceId> destIds) {
+
+        Set<Link> links = srManager.linkService.getDeviceLinks(srcId);
+        for (DeviceId destId: destIds) {
+            for (Link link : links) {
+                if (link.dst().deviceId().equals(destId)) {
+                    return link.src().port();
+                } else if (link.src().deviceId().equals(destId)) {
+                    return link.dst().port();
+                }
+            }
+        }
+
+        return null;
+    }
+
+    private static class SRObjectiveContext implements ObjectiveContext {
+        enum ObjectiveType {
+            FILTER,
+            FORWARDING
+        }
+        final DeviceId deviceId;
+        final ObjectiveType type;
+
+        SRObjectiveContext(DeviceId deviceId, ObjectiveType type) {
+            this.deviceId = deviceId;
+            this.type = type;
+        }
+        @Override
+        public void onSuccess(Objective objective) {
+            log.debug("{} objective operation successful in device {}",
+                      type.name(), deviceId);
+        }
+
+        @Override
+        public void onError(Objective objective, ObjectiveError error) {
+            log.warn("{} objective {} operation failed with error: {} in device {}",
+                     type.name(), objective, error, deviceId);
+        }
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java
new file mode 100644
index 00000000..874faabf
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingManager.java
@@ -0,0 +1,517 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.packet.Ethernet;
+import org.onlab.packet.IPv4;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.event.Event;
+import org.onosproject.segmentrouting.grouphandler.DefaultGroupHandler;
+import org.onosproject.segmentrouting.grouphandler.NeighborSet;
+import org.onosproject.segmentrouting.grouphandler.NeighborSetNextObjectiveStoreKey;
+import org.onosproject.mastership.MastershipService;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.Port;
+import org.onosproject.net.device.DeviceEvent;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.group.GroupKey;
+import org.onosproject.net.host.HostService;
+import org.onosproject.net.intent.IntentService;
+import org.onosproject.net.link.LinkEvent;
+import org.onosproject.net.link.LinkListener;
+import org.onosproject.net.link.LinkService;
+import org.onosproject.net.packet.InboundPacket;
+import org.onosproject.net.packet.PacketContext;
+import org.onosproject.net.packet.PacketProcessor;
+import org.onosproject.net.packet.PacketService;
+import org.onosproject.net.topology.TopologyService;
+import org.onosproject.segmentrouting.config.NetworkConfigManager;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.onosproject.store.service.EventuallyConsistentMapBuilder;
+import org.onosproject.store.service.StorageService;
+import org.onosproject.store.service.WallClockTimestamp;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.net.URI;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+@SuppressWarnings("ALL")
+@Service
+@Component(immediate = true)
+public class SegmentRoutingManager implements SegmentRoutingService {
+
+    private static Logger log = LoggerFactory
+            .getLogger(SegmentRoutingManager.class);
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected TopologyService topologyService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected PacketService packetService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected IntentService intentService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected HostService hostService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected FlowObjectiveService flowObjectiveService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected LinkService linkService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected MastershipService mastershipService;
+
+    protected ArpHandler arpHandler = null;
+    protected IcmpHandler icmpHandler = null;
+    protected IpHandler ipHandler = null;
+    protected RoutingRulePopulator routingRulePopulator = null;
+    protected ApplicationId appId;
+    protected DeviceConfiguration deviceConfiguration = null;
+
+
+    private DefaultRoutingHandler defaultRoutingHandler = null;
+    private TunnelHandler tunnelHandler = null;
+    private PolicyHandler policyHandler = null;
+    private InternalPacketProcessor processor = new InternalPacketProcessor();
+    private InternalEventHandler eventHandler = new InternalEventHandler();
+
+    private ScheduledExecutorService executorService = Executors
+            .newScheduledThreadPool(1);
+
+    private static ScheduledFuture<?> eventHandlerFuture = null;
+    private ConcurrentLinkedQueue<Event> eventQueue = new ConcurrentLinkedQueue<Event>();
+    private Map<DeviceId, DefaultGroupHandler> groupHandlerMap = new ConcurrentHashMap<DeviceId, DefaultGroupHandler>();
+    // Per device next objective ID store with (device id + neighbor set) as key
+    private EventuallyConsistentMap<NeighborSetNextObjectiveStoreKey,
+        Integer> nsNextObjStore = null;
+    private EventuallyConsistentMap<String, Tunnel> tunnelStore = null;
+    private EventuallyConsistentMap<String, Policy> policyStore = null;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected StorageService storageService;
+
+    private NetworkConfigManager networkConfigService = new NetworkConfigManager();;
+
+    private Object threadSchedulerLock = new Object();
+    private static int numOfEventsQueued = 0;
+    private static int numOfEventsExecuted = 0;
+    private static int numOfHandlerExecution = 0;
+    private static int numOfHandlerScheduled = 0;
+
+    private KryoNamespace.Builder kryoBuilder = null;
+
+    @Activate
+    protected void activate() {
+        appId = coreService
+                .registerApplication("org.onosproject.segmentrouting");
+
+        kryoBuilder = new KryoNamespace.Builder()
+            .register(NeighborSetNextObjectiveStoreKey.class,
+                    NeighborSet.class,
+                    DeviceId.class,
+                    URI.class,
+                    WallClockTimestamp.class,
+                    org.onosproject.cluster.NodeId.class,
+                    HashSet.class,
+                    Tunnel.class,
+                    DefaultTunnel.class,
+                    Policy.class,
+                    TunnelPolicy.class,
+                    Policy.Type.class
+            );
+
+        log.debug("Creating EC map nsnextobjectivestore");
+        EventuallyConsistentMapBuilder<NeighborSetNextObjectiveStoreKey, Integer>
+                nsNextObjMapBuilder = storageService.eventuallyConsistentMapBuilder();
+
+        nsNextObjStore = nsNextObjMapBuilder
+                .withName("nsnextobjectivestore")
+                .withSerializer(kryoBuilder)
+                .withTimestampProvider((k, v) -> new WallClockTimestamp())
+                .build();
+        log.trace("Current size {}", nsNextObjStore.size());
+
+        EventuallyConsistentMapBuilder<String, Tunnel> tunnelMapBuilder =
+                storageService.eventuallyConsistentMapBuilder();
+
+        tunnelStore = tunnelMapBuilder
+                .withName("tunnelstore")
+                .withSerializer(kryoBuilder)
+                .withTimestampProvider((k, v) -> new WallClockTimestamp())
+                .build();
+
+        EventuallyConsistentMapBuilder<String, Policy> policyMapBuilder =
+                storageService.eventuallyConsistentMapBuilder();
+
+        policyStore = policyMapBuilder
+                .withName("policystore")
+                .withSerializer(kryoBuilder)
+                .withTimestampProvider((k, v) -> new WallClockTimestamp())
+                .build();
+
+        networkConfigService.init();
+        deviceConfiguration = new DeviceConfiguration(networkConfigService);
+        arpHandler = new ArpHandler(this);
+        icmpHandler = new IcmpHandler(this);
+        ipHandler = new IpHandler(this);
+        routingRulePopulator = new RoutingRulePopulator(this);
+        defaultRoutingHandler = new DefaultRoutingHandler(this);
+        tunnelHandler = new TunnelHandler(linkService, deviceConfiguration,
+                groupHandlerMap, tunnelStore);
+        policyHandler = new PolicyHandler(appId, deviceConfiguration,
+                flowObjectiveService, tunnelHandler, policyStore);
+
+        packetService.addProcessor(processor, PacketProcessor.director(2));
+        linkService.addListener(new InternalLinkListener());
+        deviceService.addListener(new InternalDeviceListener());
+
+        for (Device device : deviceService.getDevices()) {
+            //Irrespective whether the local is a MASTER or not for this device,
+            //create group handler instance and push default TTP flow rules.
+            //Because in a multi-instance setup, instances can initiate
+            //groups for any devices. Also the default TTP rules are needed
+            //to be pushed before inserting any IP table entries for any device
+            DefaultGroupHandler groupHandler = DefaultGroupHandler
+                    .createGroupHandler(device.id(), appId,
+                                        deviceConfiguration, linkService,
+                                        flowObjectiveService,
+                                        nsNextObjStore);
+            groupHandlerMap.put(device.id(), groupHandler);
+            defaultRoutingHandler.populateTtpRules(device.id());
+        }
+
+        defaultRoutingHandler.startPopulationProcess();
+        log.info("Started");
+
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        packetService.removeProcessor(processor);
+        processor = null;
+        log.info("Stopped");
+    }
+
+
+    @Override
+    public List<Tunnel> getTunnels() {
+        return tunnelHandler.getTunnels();
+    }
+
+    @Override
+    public TunnelHandler.Result createTunnel(Tunnel tunnel) {
+        return tunnelHandler.createTunnel(tunnel);
+    }
+
+    @Override
+    public TunnelHandler.Result removeTunnel(Tunnel tunnel) {
+        for (Policy policy: policyHandler.getPolicies()) {
+            if (policy.type() == Policy.Type.TUNNEL_FLOW) {
+                TunnelPolicy tunnelPolicy = (TunnelPolicy) policy;
+                if (tunnelPolicy.tunnelId().equals(tunnel.id())) {
+                    log.warn("Cannot remove the tunnel used by a policy");
+                    return TunnelHandler.Result.TUNNEL_IN_USE;
+                }
+            }
+        }
+        return tunnelHandler.removeTunnel(tunnel);
+    }
+
+    @Override
+    public PolicyHandler.Result removePolicy(Policy policy) {
+        return policyHandler.removePolicy(policy);
+    }
+
+    @Override
+    public PolicyHandler.Result createPolicy(Policy policy) {
+        return policyHandler.createPolicy(policy);
+    }
+
+    @Override
+    public List<Policy> getPolicies() {
+        return policyHandler.getPolicies();
+    }
+
+    /**
+     * Returns the tunnel object with the tunnel ID.
+     *
+     * @param tunnelId Tunnel ID
+     * @return Tunnel reference
+     */
+    public Tunnel getTunnel(String tunnelId) {
+        return tunnelHandler.getTunnel(tunnelId);
+    }
+
+    /**
+     * Returns the GrouopKey object for the device and the NighborSet given.
+     *
+     * @param ns NeightborSet object for the GroupKey
+     * @return GroupKey object for the NeighborSet
+     */
+    public GroupKey getGroupKey(NeighborSet ns) {
+
+        for (DefaultGroupHandler groupHandler : groupHandlerMap.values()) {
+            return groupHandler.getGroupKey(ns);
+        }
+
+        return null;
+    }
+
+    /**
+     * Returns the next objective ID for the NeighborSet given. If the nextObjectiveID does not exist,
+     * a new one is created and returned.
+     *
+     * @param deviceId Device ID
+     * @param ns NegighborSet
+     * @return next objective ID
+     */
+    public int getNextObjectiveId(DeviceId deviceId, NeighborSet ns) {
+
+        if (groupHandlerMap.get(deviceId) != null) {
+            log.trace("getNextObjectiveId query in device {}", deviceId);
+            return groupHandlerMap
+                    .get(deviceId).getNextObjectiveId(ns);
+        } else {
+            log.warn("getNextObjectiveId query in device {} not found", deviceId);
+            return -1;
+        }
+    }
+
+    private class InternalPacketProcessor implements PacketProcessor {
+
+        @Override
+        public void process(PacketContext context) {
+
+            if (context.isHandled()) {
+                return;
+            }
+
+            InboundPacket pkt = context.inPacket();
+            Ethernet ethernet = pkt.parsed();
+
+            if (ethernet.getEtherType() == Ethernet.TYPE_ARP) {
+                arpHandler.processPacketIn(pkt);
+            } else if (ethernet.getEtherType() == Ethernet.TYPE_IPV4) {
+                IPv4 ipPacket = (IPv4) ethernet.getPayload();
+                ipHandler.addToPacketBuffer(ipPacket);
+                if (ipPacket.getProtocol() == IPv4.PROTOCOL_ICMP) {
+                    icmpHandler.processPacketIn(pkt);
+                } else {
+                    ipHandler.processPacketIn(pkt);
+                }
+            }
+        }
+    }
+
+    private class InternalLinkListener implements LinkListener {
+        @Override
+        public void event(LinkEvent event) {
+            if (event.type() == LinkEvent.Type.LINK_ADDED
+                    || event.type() == LinkEvent.Type.LINK_REMOVED) {
+                log.debug("Event {} received from Link Service", event.type());
+                scheduleEventHandlerIfNotScheduled(event);
+            }
+        }
+    }
+
+    private class InternalDeviceListener implements DeviceListener {
+
+        @Override
+        public void event(DeviceEvent event) {
+            /*if (mastershipService.getLocalRole(event.subject().id()) != MastershipRole.MASTER) {
+                log.debug("Local role {} is not MASTER for device {}",
+                          mastershipService.getLocalRole(event.subject().id()),
+                          event.subject().id());
+                return;
+            }*/
+
+            switch (event.type()) {
+            case DEVICE_ADDED:
+            case PORT_REMOVED:
+            case DEVICE_UPDATED:
+            case DEVICE_AVAILABILITY_CHANGED:
+                log.debug("Event {} received from Device Service", event.type());
+                scheduleEventHandlerIfNotScheduled(event);
+                break;
+            default:
+            }
+        }
+    }
+
+    private void scheduleEventHandlerIfNotScheduled(Event event) {
+
+        synchronized (threadSchedulerLock) {
+            eventQueue.add(event);
+            numOfEventsQueued++;
+
+            if ((numOfHandlerScheduled - numOfHandlerExecution) == 0) {
+                //No pending scheduled event handling threads. So start a new one.
+                eventHandlerFuture = executorService
+                        .schedule(eventHandler, 100, TimeUnit.MILLISECONDS);
+                numOfHandlerScheduled++;
+            }
+            log.trace("numOfEventsQueued {}, numOfEventHanlderScheduled {}",
+                      numOfEventsQueued,
+                      numOfHandlerScheduled);
+        }
+    }
+
+    private class InternalEventHandler implements Runnable {
+
+        @Override
+        public void run() {
+            try {
+                while (true) {
+                    Event event = null;
+                    synchronized (threadSchedulerLock) {
+                        if (!eventQueue.isEmpty()) {
+                            event = eventQueue.poll();
+                            numOfEventsExecuted++;
+                        } else {
+                            numOfHandlerExecution++;
+                            log.debug("numOfHandlerExecution {} numOfEventsExecuted {}",
+                                      numOfHandlerExecution, numOfEventsExecuted);
+                            break;
+                        }
+                    }
+                    if (event.type() == LinkEvent.Type.LINK_ADDED) {
+                        processLinkAdded((Link) event.subject());
+                    } else if (event.type() == LinkEvent.Type.LINK_REMOVED) {
+                        processLinkRemoved((Link) event.subject());
+                    //} else if (event.type() == GroupEvent.Type.GROUP_ADDED) {
+                    //    processGroupAdded((Group) event.subject());
+                    } else if (event.type() == DeviceEvent.Type.DEVICE_ADDED ||
+                            event.type() == DeviceEvent.Type.DEVICE_AVAILABILITY_CHANGED ||
+                            event.type() == DeviceEvent.Type.DEVICE_UPDATED) {
+                        if (deviceService.isAvailable(((Device) event.subject()).id())) {
+                            processDeviceAdded((Device) event.subject());
+                        }
+                    } else if (event.type() == DeviceEvent.Type.PORT_REMOVED) {
+                        processPortRemoved((Device) event.subject(),
+                                           ((DeviceEvent) event).port());
+                    } else {
+                        log.warn("Unhandled event type: {}", event.type());
+                    }
+                }
+            } catch (Exception e) {
+                log.error("SegmentRouting event handler "
+                        + "thread thrown an exception: {}", e);
+            }
+        }
+    }
+
+    private void processLinkAdded(Link link) {
+        log.debug("A new link {} was added", link.toString());
+
+        //Irrespective whether the local is a MASTER or not for this device,
+        //create group handler instance and push default TTP flow rules.
+        //Because in a multi-instance setup, instances can initiate
+        //groups for any devices. Also the default TTP rules are needed
+        //to be pushed before inserting any IP table entries for any device
+        DefaultGroupHandler groupHandler = groupHandlerMap.get(link.src()
+                .deviceId());
+        if (groupHandler != null) {
+            groupHandler.linkUp(link);
+        } else {
+            Device device = deviceService.getDevice(link.src().deviceId());
+            if (device != null) {
+                log.warn("processLinkAdded: Link Added "
+                        + "Notification without Device Added "
+                        + "event, still handling it");
+                processDeviceAdded(device);
+                groupHandler = groupHandlerMap.get(link.src()
+                                                   .deviceId());
+                groupHandler.linkUp(link);
+            }
+        }
+
+        log.trace("Starting optimized route population process");
+        defaultRoutingHandler.populateRoutingRulesForLinkStatusChange(null);
+        //log.trace("processLinkAdded: re-starting route population process");
+        //defaultRoutingHandler.startPopulationProcess();
+    }
+
+    private void processLinkRemoved(Link link) {
+        log.debug("A link {} was removed", link.toString());
+        DefaultGroupHandler groupHandler = groupHandlerMap.get(link.src().deviceId());
+        if (groupHandler != null) {
+            groupHandler.portDown(link.src().port());
+        }
+        log.trace("Starting optimized route population process");
+        defaultRoutingHandler.populateRoutingRulesForLinkStatusChange(link);
+        //log.trace("processLinkRemoved: re-starting route population process");
+        //defaultRoutingHandler.startPopulationProcess();
+    }
+
+    private void processDeviceAdded(Device device) {
+        log.debug("A new device with ID {} was added", device.id());
+        //Irrespective whether the local is a MASTER or not for this device,
+        //create group handler instance and push default TTP flow rules.
+        //Because in a multi-instance setup, instances can initiate
+        //groups for any devices. Also the default TTP rules are needed
+        //to be pushed before inserting any IP table entries for any device
+        DefaultGroupHandler dgh = DefaultGroupHandler.
+                createGroupHandler(device.id(),
+                                   appId,
+                                   deviceConfiguration,
+                                   linkService,
+                                   flowObjectiveService,
+                                   nsNextObjStore);
+        groupHandlerMap.put(device.id(), dgh);
+        defaultRoutingHandler.populateTtpRules(device.id());
+    }
+
+    private void processPortRemoved(Device device, Port port) {
+        log.debug("Port {} was removed", port.toString());
+        DefaultGroupHandler groupHandler = groupHandlerMap.get(device.id());
+        if (groupHandler != null) {
+            groupHandler.portDown(port.number());
+        }
+    }
+
+
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java
new file mode 100644
index 00000000..44bd453c
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/SegmentRoutingService.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import java.util.List;
+
+/**
+ * Segment Routing Service for REST API.
+ */
+public interface SegmentRoutingService {
+
+    /**
+     * Returns all tunnels.
+     *
+     * @return list of tunnels
+     */
+    List<Tunnel> getTunnels();
+
+    /**
+     * Creates a tunnel.
+     *
+     * @param tunnel tunnel reference to create
+     * @return WRONG_PATH if the tunnel path is wrong, ID_EXISTS if the tunnel ID
+     * exists already, TUNNEL_EXISTS if the same tunnel exists, INTERNAL_ERROR
+     * if the tunnel creation failed internally, SUCCESS if the tunnel is created
+     * successfully
+     */
+    TunnelHandler.Result createTunnel(Tunnel tunnel);
+
+    /**
+     * Returns all policies.
+     *
+     * @return list of policy
+     */
+    List<Policy> getPolicies();
+
+    /**
+     * Creates a policy.
+     *
+     * @param policy policy reference to create
+     * @return ID_EXISTS if the same policy ID exists,
+     *  POLICY_EXISTS if the same policy exists, TUNNEL_NOT_FOUND if the tunnel
+     *  does not exists, UNSUPPORTED_TYPE if the policy type is not supported,
+     *  SUCCESS if the policy is created successfully.
+     */
+    PolicyHandler.Result createPolicy(Policy policy);
+
+    /**
+     * Removes a tunnel.
+     *
+     * @param tunnel tunnel reference to remove
+     * @return TUNNEL_NOT_FOUND if the tunnel to remove does not exists,
+     * INTERNAL_ERROR if the tunnel creation failed internally, SUCCESS
+     * if the tunnel is created successfully.
+     */
+    TunnelHandler.Result removeTunnel(Tunnel tunnel);
+
+    /**
+     * Removes a policy.
+     *
+     * @param policy policy reference to remove
+     * @return POLICY_NOT_FOUND if the policy to remove does not exists,
+     * SUCCESS if it is removed successfully
+     */
+    PolicyHandler.Result removePolicy(Policy policy);
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Tunnel.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Tunnel.java
new file mode 100644
index 00000000..783d253e
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/Tunnel.java
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+import java.util.List;
+
+/**
+ * Tunnel interface.
+ */
+public interface Tunnel {
+
+    /**
+     * Returns the tunnel ID.
+     *
+     * @return tunnel ID
+     */
+    String id();
+
+    /**
+     * Returns Segment IDs for the tunnel including source and destination.
+     *
+     * @return List of Node ID
+     */
+    List<Integer> labelIds();
+
+    /**
+     * Returns the group ID for the tunnel.
+     *
+     * @return group ID
+     */
+    int groupId();
+
+    /**
+     * Sets group ID for the tunnel.
+     *
+     * @param groupId group identifier
+     */
+    void setGroupId(int groupId);
+
+    /**
+     * Sets the flag to allow to remove the group or not.
+     *
+     * @param ok the flag; true - allow to remove
+     */
+    void allowToRemoveGroup(boolean ok);
+
+    /**
+     * Checks if it is allowed to remove the group for the tunnel.
+     *
+     * @return true if allowed, false otherwise
+     */
+    boolean isAllowedToRemoveGroup();
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelHandler.java
new file mode 100644
index 00000000..820bb40a
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelHandler.java
@@ -0,0 +1,199 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting;
+
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.link.LinkService;
+import org.onosproject.segmentrouting.grouphandler.DefaultGroupHandler;
+import org.onosproject.segmentrouting.grouphandler.NeighborSet;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.slf4j.Logger;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Tunnel Handler.
+ */
+public class TunnelHandler {
+    protected final Logger log = getLogger(getClass());
+
+    private final DeviceConfiguration config;
+    private final EventuallyConsistentMap<String, Tunnel> tunnelStore;
+    private Map<DeviceId, DefaultGroupHandler> groupHandlerMap;
+    private LinkService linkService;
+
+    public enum Result {
+        SUCCESS,
+        WRONG_PATH,
+        TUNNEL_EXISTS,
+        ID_EXISTS,
+        TUNNEL_NOT_FOUND,
+        TUNNEL_IN_USE,
+        INTERNAL_ERROR
+    }
+
+    public TunnelHandler(LinkService linkService,
+                         DeviceConfiguration deviceConfiguration,
+                         Map<DeviceId, DefaultGroupHandler> groupHandlerMap,
+                         EventuallyConsistentMap<String, Tunnel> tunnelStore) {
+        this.linkService = linkService;
+        this.config = deviceConfiguration;
+        this.groupHandlerMap = groupHandlerMap;
+        this.tunnelStore = tunnelStore;
+    }
+
+    /**
+     * Creates a tunnel.
+     *
+     * @param tunnel tunnel reference to create a tunnel
+     * @return WRONG_PATH if the tunnel path is wrong, ID_EXISTS if the tunnel ID
+     * exists already, TUNNEL_EXISTS if the same tunnel exists, INTERNAL_ERROR
+     * if the tunnel creation failed internally, SUCCESS if the tunnel is created
+     * successfully
+     */
+    public Result createTunnel(Tunnel tunnel) {
+
+        if (tunnel.labelIds().isEmpty() || tunnel.labelIds().size() < 3) {
+            log.error("More than one router needs to specified to created a tunnel");
+            return Result.WRONG_PATH;
+        }
+
+        if (tunnelStore.containsKey(tunnel.id())) {
+            log.warn("The same tunnel ID exists already");
+            return Result.ID_EXISTS;
+        }
+
+        if (tunnelStore.containsValue(tunnel)) {
+            log.warn("The same tunnel exists already");
+            return Result.TUNNEL_EXISTS;
+        }
+
+        int groupId = createGroupsForTunnel(tunnel);
+        if (groupId < 0) {
+            log.error("Failed to create groups for the tunnel");
+            return Result.INTERNAL_ERROR;
+        }
+
+        tunnel.setGroupId(groupId);
+        tunnelStore.put(tunnel.id(), tunnel);
+
+        return Result.SUCCESS;
+    }
+
+    /**
+     * Removes the tunnel with the tunnel ID given.
+     *
+     * @param tunnelInfo tunnel information to delete tunnels
+     * @return TUNNEL_NOT_FOUND if the tunnel to remove does not exists,
+     * INTERNAL_ERROR if the tunnel creation failed internally, SUCCESS
+     * if the tunnel is created successfully.
+     */
+    public Result removeTunnel(Tunnel tunnelInfo) {
+
+        Tunnel tunnel = tunnelStore.get(tunnelInfo.id());
+        if (tunnel != null) {
+            DeviceId deviceId = config.getDeviceId(tunnel.labelIds().get(0));
+            if (tunnel.isAllowedToRemoveGroup()) {
+                if (groupHandlerMap.get(deviceId).removeGroup(tunnel.groupId())) {
+                    tunnelStore.remove(tunnel.id());
+                } else {
+                    log.error("Failed to remove the tunnel {}", tunnelInfo.id());
+                    return Result.INTERNAL_ERROR;
+                }
+            } else {
+                log.debug("The group is not removed because it is being used.");
+                tunnelStore.remove(tunnel.id());
+            }
+        } else {
+            log.error("No tunnel found for tunnel ID {}", tunnelInfo.id());
+            return Result.TUNNEL_NOT_FOUND;
+        }
+
+        return Result.SUCCESS;
+    }
+
+    /**
+     * Returns the tunnel with the tunnel ID given.
+     *
+     * @param tid Tunnel ID
+     * @return Tunnel reference
+     */
+    public Tunnel getTunnel(String tid) {
+        return tunnelStore.get(tid);
+    }
+
+    /**
+     * Returns all tunnels.
+     *
+     * @return list of Tunnels
+     */
+    public List<Tunnel> getTunnels() {
+        List<Tunnel> tunnels = new ArrayList<>();
+        tunnelStore.values().forEach(tunnel -> tunnels.add(
+                new DefaultTunnel((DefaultTunnel) tunnel)));
+
+        return tunnels;
+    }
+
+    private int createGroupsForTunnel(Tunnel tunnel) {
+
+        List<Integer> portNumbers;
+        final int groupError = -1;
+
+        DeviceId deviceId = config.getDeviceId(tunnel.labelIds().get(0));
+        if (deviceId == null) {
+            log.warn("No device found for SID {}", tunnel.labelIds().get(0));
+            return groupError;
+        } else if (groupHandlerMap.get(deviceId) == null) {
+            log.warn("group handler not found for {}", deviceId);
+            return groupError;
+        }
+        Set<DeviceId> deviceIds = new HashSet<>();
+        int sid = tunnel.labelIds().get(1);
+        if (config.isAdjacencySid(deviceId, sid)) {
+            portNumbers = config.getPortsForAdjacencySid(deviceId, sid);
+            for (Link link: linkService.getDeviceEgressLinks(deviceId)) {
+                for (Integer port: portNumbers) {
+                    if (link.src().port().toLong() == port) {
+                        deviceIds.add(link.dst().deviceId());
+                    }
+                }
+            }
+        } else {
+            deviceIds.add(config.getDeviceId(sid));
+        }
+
+        NeighborSet ns = new NeighborSet(deviceIds, tunnel.labelIds().get(2));
+
+        // If the tunnel reuses any existing groups, then tunnel handler
+        // should not remove the group.
+        if (groupHandlerMap.get(deviceId).hasNextObjectiveId(ns)) {
+            tunnel.allowToRemoveGroup(false);
+        } else {
+            tunnel.allowToRemoveGroup(true);
+        }
+
+        return groupHandlerMap.get(deviceId).getNextObjectiveId(ns);
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelPolicy.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelPolicy.java
new file mode 100644
index 00000000..06dbdb21
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/TunnelPolicy.java
@@ -0,0 +1,291 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+import java.util.Objects;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Tunnel Policy.
+ */
+public final class TunnelPolicy implements Policy {
+
+    private final Type type;
+    private final String id;
+    private final int priority;
+    private final String tunnelId;
+    private String dstIp;
+    private String srcIp;
+    private String ipProto;
+    private short srcPort;
+    private short dstPort;
+
+    private TunnelPolicy(String policyId, Type type, int priority, String tunnelId, String srcIp,
+                         String dstIp, String ipProto, short srcPort, short dstPort) {
+        this.id = checkNotNull(policyId);
+        this.type = type;
+        this.tunnelId = tunnelId;
+        this.priority = priority;
+        this.dstIp = dstIp;
+        this.srcIp = srcIp;
+        this.ipProto = ipProto;
+        this.srcPort = srcPort;
+        this.dstPort = dstPort;
+
+    }
+
+    /**
+     * Creates a TunnelPolicy reference.
+     *
+     * @param p TunnelPolicy reference
+     */
+    public TunnelPolicy(TunnelPolicy p) {
+        this.id = p.id;
+        this.type = p.type;
+        this.tunnelId = p.tunnelId;
+        this.priority = p.priority;
+        this.srcIp = p.srcIp;
+        this.dstIp = p.dstIp;
+        this.ipProto = p.ipProto;
+        this.srcPort = p.srcPort;
+        this.dstPort = p.dstPort;
+    }
+
+    /**
+     * Returns the TunnelPolicy builder reference.
+     *
+     * @return TunnelPolicy builder
+     */
+    public static TunnelPolicy.Builder builder() {
+        return new Builder();
+    }
+
+    @Override
+    public String id() {
+        return this.id;
+    }
+
+    @Override
+    public int priority() {
+        return priority;
+    }
+
+    @Override
+    public Type type() {
+        return type;
+    }
+
+    @Override
+    public String srcIp() {
+        return srcIp;
+    }
+
+    @Override
+    public String dstIp() {
+        return dstIp;
+    }
+
+    @Override
+    public String ipProto() {
+        return ipProto;
+    }
+
+    @Override
+    public short srcPort() {
+        return srcPort;
+    }
+
+    @Override
+    public short dstPort() {
+        return dstPort;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (o instanceof TunnelPolicy) {
+            TunnelPolicy that = (TunnelPolicy) o;
+            // We do not compare the policy ID
+            if (this.type.equals(that.type) &&
+                    this.tunnelId.equals(that.tunnelId) &&
+                    this.priority == that.priority &&
+                    this.srcIp.equals(that.srcIp) &&
+                    this.dstIp.equals(that.dstIp) &&
+                    this.srcPort == that.srcPort &&
+                    this.dstPort == that.dstPort &&
+                    this.ipProto.equals(that.ipProto)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, tunnelId, srcIp, dstIp, ipProto,
+                srcPort, dstPort, priority);
+    }
+
+    /**
+     * Returns the tunnel ID of the policy.
+     *
+     * @return Tunnel ID
+     */
+    public String tunnelId() {
+        return this.tunnelId;
+    }
+
+
+    /**
+     * Tunnel Policy Builder.
+     */
+    public static final class Builder {
+
+        private String id;
+        private Type type;
+        private int priority;
+        private String tunnelId;
+        private String dstIp;
+        private String srcIp;
+        private String ipProto;
+        private short srcPort;
+        private short dstPort;
+
+        /**
+         * Sets the policy Id.
+         *
+         * @param id policy Id
+         * @return Builder object
+         */
+        public Builder setPolicyId(String id) {
+            this.id = id;
+
+            return this;
+        }
+
+        /**
+         * Sets the policy type.
+         *
+         * @param type policy type
+         * @return Builder object
+         */
+        public Builder setType(Type type) {
+            this.type = type;
+
+            return this;
+        }
+
+        /**
+         * Sets the source IP address.
+         *
+         * @param srcIp source IP address
+         * @return Builder object
+         */
+        public Builder setSrcIp(String srcIp) {
+            this.srcIp = srcIp;
+
+            return this;
+        }
+
+        /**
+         * Sets the destination IP address.
+         *
+         * @param dstIp destination IP address
+         * @return Builder object
+         */
+        public Builder setDstIp(String dstIp) {
+            this.dstIp = dstIp;
+
+            return this;
+        }
+
+        /**
+         * Sets the IP protocol.
+         *
+         * @param proto IP protocol
+         * @return Builder object
+         */
+        public Builder setIpProto(String proto) {
+            this.ipProto = proto;
+
+            return this;
+        }
+
+        /**
+         * Sets the source port.
+         *
+         * @param srcPort source port
+         * @return Builder object
+         */
+        public Builder setSrcPort(short srcPort) {
+            this.srcPort = srcPort;
+
+            return this;
+        }
+
+        /**
+         * Sets the destination port.
+         *
+         * @param dstPort destination port
+         * @return Builder object
+         */
+        public Builder setDstPort(short dstPort) {
+            this.dstPort = dstPort;
+
+            return this;
+        }
+
+        /**
+         * Sets the priority of the policy.
+         *
+         * @param p priority
+         * @return Builder object
+         */
+        public Builder setPriority(int p) {
+            this.priority = p;
+
+            return this;
+        }
+
+        /**
+         * Sets the tunnel Id.
+         *
+         * @param tunnelId tunnel Id
+         * @return Builder object
+         */
+        public Builder setTunnelId(String tunnelId) {
+            this.tunnelId = tunnelId;
+
+            return this;
+        }
+
+        /**
+         * Builds the policy.
+         *
+         * @return Tunnel Policy reference
+         */
+        public Policy build() {
+            return new TunnelPolicy(id, type, priority, tunnelId, srcIp, dstIp,
+                    ipProto, srcPort, dstPort);
+        }
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyAddCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyAddCommand.java
new file mode 100644
index 00000000..b00633cd
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyAddCommand.java
@@ -0,0 +1,132 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.Policy;
+import org.onosproject.segmentrouting.PolicyHandler;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.TunnelPolicy;
+
+/**
+ * Command to add a new policy.
+ */
+@Command(scope = "onos", name = "srpolicy-add",
+        description = "Create a new policy")
+public class PolicyAddCommand extends AbstractShellCommand {
+
+    // TODO: Need to support skipping some parameters
+
+    @Argument(index = 0, name = "ID",
+            description = "policy ID",
+            required = true, multiValued = false)
+    String policyId;
+
+    @Argument(index = 1, name = "priority",
+            description = "priority",
+            required = true, multiValued = false)
+    int priority;
+
+    @Argument(index = 2, name = "src_IP",
+            description = "src IP",
+            required = false, multiValued = false)
+    String srcIp;
+
+    @Argument(index = 3, name = "src_port",
+            description = "src port",
+            required = false, multiValued = false)
+    short srcPort;
+
+    @Argument(index = 4, name = "dst_IP",
+            description = "dst IP",
+            required = false, multiValued = false)
+    String dstIp;
+
+    @Argument(index = 5, name = "dst_port",
+            description = "dst port",
+            required = false, multiValued = false)
+    short dstPort;
+
+    @Argument(index = 6, name = "proto",
+            description = "IP protocol",
+            required = false, multiValued = false)
+    String proto;
+
+    @Argument(index = 7, name = "policy_type",
+            description = "policy type",
+            required = true, multiValued = false)
+    String policyType;
+
+    @Argument(index = 8, name = "tunnel_ID",
+            description = "tunnel ID",
+            required = false, multiValued = false)
+    String tunnelId;
+
+    @Override
+    protected void execute() {
+
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        TunnelPolicy.Builder tpb = TunnelPolicy.builder().setPolicyId(policyId);
+        tpb.setPriority(priority);
+        tpb.setType(Policy.Type.valueOf(policyType));
+
+        if (srcIp != null) {
+            tpb.setSrcIp(srcIp);
+        }
+        if (dstIp != null) {
+            tpb.setDstIp(dstIp);
+        }
+        if (srcPort != 0) {
+            tpb.setSrcPort(srcPort);
+        }
+        if (dstPort != 0) {
+            tpb.setDstPort(dstPort);
+        }
+        if (!proto.equals("ip")) {
+            tpb.setIpProto(proto);
+        }
+        if (Policy.Type.valueOf(policyType) == Policy.Type.TUNNEL_FLOW) {
+            if (tunnelId == null) {
+                error("tunnel ID must be specified for TUNNEL_FLOW policy");
+                return;
+            }
+            tpb.setTunnelId(tunnelId);
+        }
+        PolicyHandler.Result result = srService.createPolicy(tpb.build());
+
+        switch (result) {
+            case POLICY_EXISTS:
+                error("the same policy exists");
+                break;
+            case ID_EXISTS:
+                error("the same policy ID exists");
+                break;
+            case TUNNEL_NOT_FOUND:
+                error("the tunnel is not found");
+                break;
+            case UNSUPPORTED_TYPE:
+                error("the policy type specified is not supported");
+                break;
+            default:
+                break;
+        }
+
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyListCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyListCommand.java
new file mode 100644
index 00000000..929c98c5
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyListCommand.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.Policy;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.TunnelPolicy;
+
+/**
+ * Command to show the list of policies.
+ */
+@Command(scope = "onos", name = "srpolicy-list",
+        description = "Lists all policies")
+public class PolicyListCommand extends AbstractShellCommand {
+
+    private static final String FORMAT_MAPPING_TUNNEL =
+            "  id=%s, type=%s,  prio=%d, src=%s, port=%d, dst=%s, port=%d, proto=%s, tunnel=%s";
+
+    @Override
+    protected void execute() {
+
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        srService.getPolicies().forEach(policy -> printPolicy(policy));
+    }
+
+    private void printPolicy(Policy policy) {
+        if (policy.type() == Policy.Type.TUNNEL_FLOW) {
+            print(FORMAT_MAPPING_TUNNEL, policy.id(), policy.type(), policy.priority(),
+                    policy.srcIp(), policy.srcPort(), policy.dstIp(), policy.dstPort(),
+                    (policy.ipProto() == null) ? "" : policy.ipProto(),
+                    ((TunnelPolicy) policy).tunnelId());
+        }
+    }
+}
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyRemoveCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyRemoveCommand.java
new file mode 100644
index 00000000..34fe40d8
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/PolicyRemoveCommand.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.PolicyHandler;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.TunnelPolicy;
+
+/**
+ * Command to remove a policy.
+ */
+@Command(scope = "onos", name = "srpolicy-remove",
+        description = "Remove a policy")
+public class PolicyRemoveCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "policy ID",
+            description = "policy ID",
+            required = true, multiValued = false)
+    String policyId;
+
+    @Override
+    protected void execute() {
+
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        TunnelPolicy.Builder tpb = TunnelPolicy.builder().setPolicyId(policyId);
+        PolicyHandler.Result result = srService.removePolicy(tpb.build());
+        if (result == PolicyHandler.Result.POLICY_NOT_FOUND) {
+            print("ERROR: the policy is not found");
+        }
+    }
+}
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelAddCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelAddCommand.java
new file mode 100644
index 00000000..bb0ae549
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelAddCommand.java
@@ -0,0 +1,80 @@
+
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.DefaultTunnel;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.Tunnel;
+import org.onosproject.segmentrouting.TunnelHandler;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.StringTokenizer;
+
+/**
+ * Command to add a new tunnel.
+ */
+@Command(scope = "onos", name = "srtunnel-add",
+        description = "Create a new tunnel")
+public class TunnelAddCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "tunnel ID",
+            description = "tunnel ID",
+            required = true, multiValued = false)
+    String tunnelId;
+
+    @Argument(index = 1, name = "label path",
+            description = "label path",
+            required = true, multiValued = false)
+    String labels;
+
+
+    @Override
+    protected void execute() {
+
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        List<Integer> labelIds = new ArrayList<>();
+        StringTokenizer strToken = new StringTokenizer(labels, ",");
+        while (strToken.hasMoreTokens()) {
+            labelIds.add(Integer.valueOf(strToken.nextToken()));
+        }
+        Tunnel tunnel = new DefaultTunnel(tunnelId, labelIds);
+
+        TunnelHandler.Result result = srService.createTunnel(tunnel);
+        switch (result) {
+            case ID_EXISTS:
+                print("ERROR: the same tunnel ID exists");
+                break;
+            case TUNNEL_EXISTS:
+                print("ERROR: the same tunnel exists");
+                break;
+            case INTERNAL_ERROR:
+                print("ERROR: internal tunnel creation error");
+                break;
+            case WRONG_PATH:
+                print("ERROR: the tunnel path is wrong");
+                break;
+            default:
+                break;
+        }
+    }
+}
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelListCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelListCommand.java
new file mode 100644
index 00000000..fe510783
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelListCommand.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.Tunnel;
+
+/**
+ * Command to show the list of tunnels.
+ */
+@Command(scope = "onos", name = "srtunnel-list",
+        description = "Lists all tunnels")
+public class TunnelListCommand extends AbstractShellCommand {
+
+    private static final String FORMAT_MAPPING =
+            "  id=%s, path=%s";
+
+    @Override
+    protected void execute() {
+
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        srService.getTunnels().forEach(tunnel -> printTunnel(tunnel));
+    }
+
+    private void printTunnel(Tunnel tunnel) {
+        print(FORMAT_MAPPING, tunnel.id(), tunnel.labelIds());
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelRemoveCommand.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelRemoveCommand.java
new file mode 100644
index 00000000..cca22c30
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/TunnelRemoveCommand.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.cli;
+
+
+import com.google.common.collect.Lists;
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onosproject.cli.AbstractShellCommand;
+import org.onosproject.segmentrouting.DefaultTunnel;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.Tunnel;
+import org.onosproject.segmentrouting.TunnelHandler;
+
+/**
+ * Command to remove a tunnel.
+ */
+@Command(scope = "onos", name = "srtunnel-remove",
+        description = "Remove a tunnel")
+public class TunnelRemoveCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "tunnel ID",
+            description = "tunnel ID",
+            required = true, multiValued = false)
+    String tunnelId;
+
+    @Override
+    protected void execute() {
+        SegmentRoutingService srService =
+                AbstractShellCommand.get(SegmentRoutingService.class);
+
+        Tunnel tunnel = new DefaultTunnel(tunnelId, Lists.newArrayList());
+        TunnelHandler.Result result = srService.removeTunnel(tunnel);
+        switch (result) {
+            case TUNNEL_IN_USE:
+                print("ERROR: the tunnel is still in use");
+                break;
+            case TUNNEL_NOT_FOUND:
+                print("ERROR: the tunnel is not found");
+                break;
+            default:
+                break;
+        }
+    }
+}
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/package-info.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/package-info.java
new file mode 100644
index 00000000..1a9d3c78
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/cli/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Segment routing application CLI handlers.
+ */
+package org.onosproject.segmentrouting.cli;
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfig.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfig.java
new file mode 100644
index 00000000..6ae0779e
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfig.java
@@ -0,0 +1,336 @@
+package org.onosproject.segmentrouting.config;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import org.onosproject.net.DeviceId;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.databind.JsonNode;
+
+/**
+ * Public class corresponding to JSON described data model. Defines the network
+ * configuration at startup.
+ */
+public class NetworkConfig {
+    protected static final Logger log = LoggerFactory.getLogger(NetworkConfig.class);
+
+    @SuppressWarnings("unused")
+    private String comment;
+
+    private Boolean restrictSwitches;
+    private Boolean restrictLinks;
+    private List<SwitchConfig> switches;
+    private List<LinkConfig> links;
+
+    /**
+     * Default constructor.
+     */
+    public NetworkConfig() {
+        switches = new ArrayList<SwitchConfig>();
+        links = new ArrayList<LinkConfig>();
+    }
+
+    @JsonProperty("comment")
+    public void setComment(String c) {
+        log.trace("NetworkConfig: comment={}", c);
+        comment = c;
+    }
+
+    @JsonProperty("restrictSwitches")
+    public void setRestrictSwitches(boolean rs) {
+        log.trace("NetworkConfig: restrictSwitches={}", rs);
+        restrictSwitches = rs;
+    }
+
+    /**
+     * Returns default restrict configuration for switches.
+     *
+     * @return boolean
+     */
+    public Boolean getRestrictSwitches() {
+        return restrictSwitches;
+    }
+
+    @JsonProperty("restrictLinks")
+    public void setRestrictLinks(boolean rl) {
+        log.trace("NetworkConfig: restrictLinks={}", rl);
+        restrictLinks = rl;
+    }
+
+    /**
+     * Returns default restrict configuration for links.
+     *
+     * @return boolean
+     */
+    public Boolean getRestrictLinks() {
+        return restrictLinks;
+    }
+
+    /**
+     * Returns configuration for switches.
+     *
+     * @return list of switch configuration
+     */
+    public List<SwitchConfig> getSwitchConfig() {
+        return switches;
+    }
+
+    @JsonProperty("switchConfig")
+    public void setSwitchConfig(List<SwitchConfig> switches2) {
+        log.trace("NetworkConfig: switchConfig={}", switches2);
+        this.switches = switches2;
+    }
+
+    /**
+     * Java class corresponding to JSON described switch
+     * configuration data model.
+     */
+    public static class SwitchConfig {
+        protected String nodeDpid;
+        protected String name;
+        protected String type;
+        protected boolean allowed;
+        protected double latitude;
+        protected double longitude;
+        protected Map<String, JsonNode> params;
+        protected Map<String, String> publishAttributes;
+        protected DeviceId dpid;
+
+        /**
+         * Returns the configured "name" of a switch.
+         *
+         * @return string
+         */
+        public String getName() {
+            return name;
+        }
+
+        @JsonProperty("name")
+        public void setName(String name) {
+            log.trace("SwitchConfig: name={}", name);
+            this.name = name;
+        }
+
+        /**
+         * Returns the data plane identifier of a switch.
+         *
+         * @return ONOS device identifier
+         */
+        public DeviceId getDpid() {
+            return dpid;
+        }
+
+        public void setDpid(DeviceId dpid) {
+            this.dpid = dpid;
+            this.nodeDpid = dpid.toString();
+        }
+
+        /**
+         * Returns the data plane identifier of a switch.
+         *
+         * @return string
+         */
+        public String getNodeDpid() {
+            return nodeDpid;
+        }
+
+        // mapper sets both DeviceId and string fields for dpid
+        @JsonProperty("nodeDpid")
+        public void setNodeDpid(String nodeDpid) {
+            log.trace("SwitchConfig: nodeDpid={}", nodeDpid);
+            this.nodeDpid = nodeDpid;
+            this.dpid = DeviceId.deviceId(nodeDpid);
+        }
+
+        /**
+         * Returns the type of a switch.
+         *
+         * @return string
+         */
+        public String getType() {
+            return type;
+        }
+
+        @JsonProperty("type")
+        public void setType(String type) {
+            log.trace("SwitchConfig: type={}", type);
+            this.type = type;
+        }
+
+        /**
+         * Returns the latitude of a switch.
+         *
+         * @return double
+         */
+        public double getLatitude() {
+            return latitude;
+        }
+
+        @JsonProperty("latitude")
+        public void setLatitude(double latitude) {
+            log.trace("SwitchConfig: latitude={}", latitude);
+            this.latitude = latitude;
+        }
+
+        /**
+         * Returns the longitude of a switch.
+         *
+         * @return double
+         */
+        public double getLongitude() {
+            return longitude;
+        }
+
+        @JsonProperty("longitude")
+        public void setLongitude(double longitude) {
+            log.trace("SwitchConfig: longitude={}", longitude);
+            this.longitude = longitude;
+        }
+
+        /**
+         * Returns the allowed flag for a switch.
+         *
+         * @return boolean
+         */
+        public boolean isAllowed() {
+            return allowed;
+        }
+
+        @JsonProperty("allowed")
+        public void setAllowed(boolean allowed) {
+            this.allowed = allowed;
+        }
+
+        /**
+         * Returns the additional configured parameters of a switch.
+         *
+         * @return key value map
+         */
+        public Map<String, JsonNode> getParams() {
+            return params;
+        }
+
+        @JsonProperty("params")
+        public void setParams(Map<String, JsonNode> params) {
+            this.params = params;
+        }
+
+        /**
+         * Reserved for future use.
+         *
+         * @return key value map
+         */
+        public Map<String, String> getPublishAttributes() {
+            return publishAttributes;
+        }
+
+        @JsonProperty("publishAttributes")
+        public void setPublishAttributes(Map<String, String> publishAttributes) {
+            this.publishAttributes = publishAttributes;
+        }
+
+    }
+
+    @JsonProperty("linkConfig")
+    public void setLinkConfig(List<LinkConfig> links2) {
+        this.links = links2;
+    }
+
+    /**
+     * Reserved for future use.
+     *
+     * @return list of configured link configuration
+     */
+    public List<LinkConfig> getLinkConfig() {
+        return links;
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class LinkConfig {
+        protected String type;
+        protected Boolean allowed;
+        protected DeviceId dpid1;
+        protected DeviceId dpid2;
+        protected String nodeDpid1;
+        protected String nodeDpid2;
+        protected Map<String, JsonNode> params;
+        protected Map<String, String> publishAttributes;
+
+        public String getType() {
+            return type;
+        }
+
+        public void setType(String type) {
+            this.type = type;
+        }
+
+        public Boolean isAllowed() {
+            return allowed;
+        }
+
+        public void setAllowed(Boolean allowed) {
+            this.allowed = allowed;
+        }
+
+        public String getNodeDpid1() {
+            return nodeDpid1;
+        }
+
+        // mapper sets both long and string fields for dpid
+        public void setNodeDpid1(String nodeDpid1) {
+            this.nodeDpid1 = nodeDpid1;
+            this.dpid1 = DeviceId.deviceId(nodeDpid1);
+        }
+
+        public String getNodeDpid2() {
+            return nodeDpid2;
+        }
+
+        // mapper sets both long and string fields for dpid
+        public void setNodeDpid2(String nodeDpid2) {
+            this.nodeDpid2 = nodeDpid2;
+            this.dpid2 = DeviceId.deviceId(nodeDpid2);
+        }
+
+        public DeviceId getDpid1() {
+            return dpid1;
+        }
+
+        public void setDpid1(DeviceId dpid1) {
+            this.dpid1 = dpid1;
+            this.nodeDpid1 = dpid1.toString();
+        }
+
+        public DeviceId getDpid2() {
+            return dpid2;
+        }
+
+        public void setDpid2(DeviceId dpid2) {
+            this.dpid2 = dpid2;
+            this.nodeDpid2 = dpid2.toString();
+        }
+
+        public Map<String, JsonNode> getParams() {
+            return params;
+        }
+
+        public void setParams(Map<String, JsonNode> params) {
+            this.params = params;
+        }
+
+        public Map<String, String> getPublishAttributes() {
+            return publishAttributes;
+        }
+
+        public void setPublishAttributes(Map<String, String> publishAttributes) {
+            this.publishAttributes = publishAttributes;
+        }
+    }
+}
+
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigException.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigException.java
new file mode 100644
index 00000000..91942216
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigException.java
@@ -0,0 +1,200 @@
+package org.onosproject.segmentrouting.config;
+
+import org.onosproject.net.DeviceId;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * NetworkConfigExceptions specifies a set of unchecked runtime exceptions that
+ * can be thrown by the {@link NetworkConfigManager}. It indicates errors that
+ * must be fixed in the config file before controller execution can proceed.
+ */
+public class NetworkConfigException extends RuntimeException {
+
+    private static final long serialVersionUID = 4959684709803000652L;
+    protected static final Logger log = LoggerFactory
+            .getLogger(NetworkConfigException.class);
+
+    /**
+     * Exception for duplicate device identifier configuration.
+     */
+    public static class DuplicateDpid extends RuntimeException {
+        private static final long serialVersionUID = 5491113234592145335L;
+
+        public DuplicateDpid(DeviceId dpid) {
+            super();
+            log.error("Duplicate dpid found in switch-config Dpid:{}",
+                    dpid);
+        }
+    }
+
+    /**
+     * Exception for duplicate device name configuration.
+     */
+    public static class DuplicateName extends RuntimeException {
+        private static final long serialVersionUID = -4090171438031376129L;
+
+        public DuplicateName(String name) {
+            super();
+            log.error("Duplicate name found in switch-config name:{}", name);
+        }
+    }
+
+    /**
+     * Exception for unspecified device identifier for a switch.
+     */
+    public static class DpidNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -8494418855597117254L;
+
+        public DpidNotSpecified(String name) {
+            super();
+            log.error("Dpid not specified for switch-config name:{}", name);
+        }
+    }
+
+    /**
+     * Exception for unspecified device name for a switch.
+     */
+    public static class NameNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -3518881744110422891L;
+
+        public NameNotSpecified(DeviceId dpid) {
+            super();
+            log.error("Name not specified for switch-config dpid:{}",
+                    dpid);
+        }
+    }
+
+    /**
+     * Exception for unspecified device type for a switch.
+     */
+    public static class SwitchTypeNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = 2527453336226053753L;
+
+        public SwitchTypeNotSpecified(DeviceId dpid) {
+            super();
+            log.error("Switch type not specified for switch-config dpid:{}",
+                    dpid);
+        }
+    }
+
+    /**
+     * Exception for unknown device type configured for a switch.
+     */
+    public static class UnknownSwitchType extends RuntimeException {
+        private static final long serialVersionUID = 7758418165512249170L;
+
+        public UnknownSwitchType(String type, String name) {
+            super();
+            log.error("Unknown switch type {} for switch name:{}", type, name);
+        }
+    }
+
+    /**
+     * Exception for missing required parameter configuration for a switch.
+     */
+    public static class ParamsNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = 6247582323691265513L;
+
+        public ParamsNotSpecified(String name) {
+            super();
+            log.error("Params required - not specified for switch:{}", name);
+        }
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class LinkTypeNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -2089470389588542215L;
+
+        public LinkTypeNotSpecified(String dpid1, String dpid2) {
+            super();
+            log.error("Link type not specified for link-config between "
+                    + "dpid1:{} and dpid2:{}", dpid1, dpid2);
+        }
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class LinkDpidNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -5701825916378616004L;
+
+        public LinkDpidNotSpecified(String dpid1, String dpid2) {
+            super();
+            if (dpid1 == null) {
+                log.error("nodeDpid1 not specified for link-config ");
+            }
+            if (dpid2 == null) {
+                log.error("nodeDpid2 not specified for link-config ");
+            }
+        }
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class LinkForUnknownSwitchConfig extends RuntimeException {
+        private static final long serialVersionUID = -2910458439881964094L;
+
+        public LinkForUnknownSwitchConfig(String dpid) {
+            super();
+            log.error("Link configuration was specified for a switch-dpid {} "
+                    + "that has not been configured", dpid);
+        }
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class UnknownLinkType extends RuntimeException {
+        private static final long serialVersionUID = -5505376193106542305L;
+
+        public UnknownLinkType(String linktype, String dpid1, String dpid2) {
+            super();
+            log.error("unknown link type {} for links between dpid1:{} "
+                    + "and dpid2:{}", linktype, dpid1, dpid2);
+        }
+    }
+
+    /**
+     * Exception for generic configuration errors.
+     */
+    public static class ErrorConfig extends RuntimeException {
+        private static final long serialVersionUID = -2827406314700193147L;
+
+        public ErrorConfig(String errorMsg) {
+            super();
+            log.error(errorMsg);
+        }
+
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class SwitchDpidNotConverted extends RuntimeException {
+        private static final long serialVersionUID = 5640347104590170426L;
+
+        public SwitchDpidNotConverted(String name) {
+            super();
+            log.error("Switch dpid specified as a HexString {} does not match "
+                    + "with long value", name);
+        }
+    }
+
+    /**
+     * Reserved for future use.
+     */
+    public static class LinkDpidNotConverted extends RuntimeException {
+        private static final long serialVersionUID = 2397245646094080774L;
+
+        public LinkDpidNotConverted(String dpid1, String dpid2) {
+            log.error("Dpids expressed as HexStrings for links between dpid1:{} "
+                    + "and dpid2:{} do not match with long values", dpid1, dpid2);
+        }
+    }
+
+}
+
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigManager.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigManager.java
new file mode 100644
index 00000000..44e4f1c6
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigManager.java
@@ -0,0 +1,323 @@
+package org.onosproject.segmentrouting.config;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.segmentrouting.config.NetworkConfig.LinkConfig;
+import org.onosproject.segmentrouting.config.NetworkConfig.SwitchConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.core.JsonParseException;
+import com.fasterxml.jackson.databind.JsonMappingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+/**
+ * NetworkConfigManager manages all network configuration for switches, links
+ * and any other state that needs to be configured for correct network
+ * operation.
+ *
+ */
+public class NetworkConfigManager implements NetworkConfigService {
+    protected static final Logger log = LoggerFactory
+            .getLogger(NetworkConfigManager.class);
+    private static final String CONFIG_DIR = "../config";
+    private static final String DEFAULT_CONFIG_FILE = "segmentrouting.conf";
+    private final String configFileName = DEFAULT_CONFIG_FILE;
+    /**
+     * JSON Config file needs to use one of the following types for defining the
+     * kind of switch or link it wishes to configure.
+     */
+    public static final String SEGMENT_ROUTER = "Router_SR";
+
+    public static final String PKT_LINK = "pktLink";
+
+    NetworkConfig networkConfig;
+    private ConcurrentMap<DeviceId, SwitchConfig> configuredSwitches;
+    private ConcurrentMap<Link, LinkConfig> configuredLinks;
+    private Map<String, DeviceId> nameToDpid;
+
+    @Override
+    public SwitchConfigStatus checkSwitchConfig(DeviceId dpid) {
+        SwitchConfig swc = configuredSwitches.get(dpid);
+        if (networkConfig.getRestrictSwitches()) {
+            // default deny behavior
+            if (swc == null) {
+                // switch is not configured - we deny this switch
+                return new SwitchConfigStatus(NetworkConfigState.DENY, null,
+                        "Switch not configured, in network denying switches by default.");
+            }
+            if (swc.isAllowed()) {
+                // switch is allowed in config, return configured attributes
+                return new SwitchConfigStatus(NetworkConfigState.ACCEPT_ADD, swc);
+            } else {
+                // switch has been configured off (administratively down)
+                return new SwitchConfigStatus(NetworkConfigState.DENY, null,
+                        "Switch configured down (allowed=false).");
+            }
+        } else {
+            // default allow behavior
+            if (swc == null) {
+                // no config to add
+                return new SwitchConfigStatus(NetworkConfigState.ACCEPT, null);
+            }
+            if (swc.isAllowed()) {
+                // switch is allowed in config, return configured attributes
+                return new SwitchConfigStatus(NetworkConfigState.ACCEPT_ADD, swc);
+            } else {
+                // switch has been configured off (administratively down)
+                return new SwitchConfigStatus(NetworkConfigState.DENY, null,
+                        "Switch configured down (allowed=false).");
+            }
+        }
+
+    }
+
+    @Override
+    public LinkConfigStatus checkLinkConfig(Link linkTuple) {
+        LinkConfig lkc = getConfiguredLink(linkTuple);
+        // links are always disallowed if any one of the nodes that make up the
+        // link are disallowed
+        DeviceId linkNode1 = linkTuple.src().deviceId();
+        SwitchConfigStatus scs1 = checkSwitchConfig(linkNode1);
+        if (scs1.getConfigState() == NetworkConfigState.DENY) {
+            return new LinkConfigStatus(NetworkConfigState.DENY, null,
+                    "Link-node: " + linkNode1 + " denied by config: " + scs1.getMsg());
+        }
+        DeviceId linkNode2 = linkTuple.dst().deviceId();
+        SwitchConfigStatus scs2 = checkSwitchConfig(linkNode2);
+        if (scs2.getConfigState() == NetworkConfigState.DENY) {
+            return new LinkConfigStatus(NetworkConfigState.DENY, null,
+                    "Link-node: " + linkNode2 + " denied by config: " + scs2.getMsg());
+        }
+        if (networkConfig.getRestrictLinks()) {
+            // default deny behavior
+            if (lkc == null) {
+                // link is not configured - we deny this link
+                return new LinkConfigStatus(NetworkConfigState.DENY, null,
+                        "Link not configured, in network denying links by default.");
+            }
+            if (lkc.isAllowed()) {
+                // link is allowed in config, return configured attributes
+                return new LinkConfigStatus(NetworkConfigState.ACCEPT_ADD, lkc);
+            } else {
+                // link has been configured off (administratively down)
+                return new LinkConfigStatus(NetworkConfigState.DENY, null,
+                        "Link configured down (allowed=false).");
+            }
+        } else {
+            // default allow behavior
+            if (lkc == null) {
+                // no config to add
+                return new LinkConfigStatus(NetworkConfigState.ACCEPT, null);
+            }
+            if (lkc.isAllowed()) {
+                // link is allowed in config, return configured attributes
+                return new LinkConfigStatus(NetworkConfigState.ACCEPT_ADD, lkc);
+            } else {
+                // link has been configured off (administratively down)
+                return new LinkConfigStatus(NetworkConfigState.DENY, null,
+                        "Link configured down (allowed=false).");
+            }
+        }
+
+    }
+
+    @Override
+    public List<SwitchConfig> getConfiguredAllowedSwitches() {
+        List<SwitchConfig> allowed = new ArrayList<SwitchConfig>();
+        for (SwitchConfig swc : configuredSwitches.values()) {
+            if (swc.isAllowed()) {
+                allowed.add(swc);
+            }
+        }
+        return allowed;
+    }
+
+    @Override
+    public List<LinkConfig> getConfiguredAllowedLinks() {
+        List<LinkConfig> allowed = new ArrayList<LinkConfig>();
+        for (LinkConfig lkc : configuredLinks.values()) {
+            if (lkc.isAllowed()) {
+                allowed.add(lkc);
+            }
+        }
+        return allowed;
+    }
+
+    @Override
+    public DeviceId getDpidForName(String name) {
+        if (nameToDpid.get(name) != null) {
+            return nameToDpid.get(name);
+        }
+        return null;
+    }
+
+    // **************
+    // Private methods
+    // **************
+
+    private void loadNetworkConfig() {
+        File configFile = new File(CONFIG_DIR, configFileName);
+        ObjectMapper mapper = new ObjectMapper();
+        networkConfig = new NetworkConfig();
+
+        try {
+            networkConfig = mapper.readValue(configFile,
+                                             NetworkConfig.class);
+        } catch (JsonParseException e) {
+            String err = String.format("JsonParseException while loading network "
+                    + "config from file: %s: %s", configFileName,
+                    e.getMessage());
+            throw new NetworkConfigException.ErrorConfig(err);
+        } catch (JsonMappingException e) {
+            String err = String.format(
+                    "JsonMappingException while loading network config "
+                            + "from file: %s: %s",
+                            configFileName,
+                            e.getMessage());
+            throw new NetworkConfigException.ErrorConfig(err);
+        } catch (IOException e) {
+            String err = String.format("IOException while loading network config "
+                    + "from file: %s %s", configFileName, e.getMessage());
+            throw new NetworkConfigException.ErrorConfig(err);
+        }
+
+        log.info("Network config specifies: {} switches and {} links",
+                (networkConfig.getRestrictSwitches())
+                        ? networkConfig.getSwitchConfig().size() : "default allow",
+                        (networkConfig.getRestrictLinks())
+                        ? networkConfig.getLinkConfig().size() : "default allow");
+    }
+
+    private void parseNetworkConfig() {
+        List<SwitchConfig> swConfList = networkConfig.getSwitchConfig();
+        List<LinkConfig> lkConfList = networkConfig.getLinkConfig();
+        validateSwitchConfig(swConfList);
+        createTypeSpecificSwitchConfig(swConfList);
+        validateLinkConfig(lkConfList);
+        createTypeSpecificLinkConfig(lkConfList);
+        // TODO validate reachability matrix 'names' for configured dpids
+    }
+
+    private void createTypeSpecificSwitchConfig(List<SwitchConfig> swConfList) {
+        for (SwitchConfig swc : swConfList) {
+            nameToDpid.put(swc.getName(), swc.getDpid());
+            String swtype = swc.getType();
+            switch (swtype) {
+            case SEGMENT_ROUTER:
+                SwitchConfig sr = new SegmentRouterConfig(swc);
+                configuredSwitches.put(sr.getDpid(), sr);
+                break;
+            default:
+                throw new NetworkConfigException.UnknownSwitchType(swtype,
+                        swc.getName());
+            }
+        }
+    }
+
+    private void createTypeSpecificLinkConfig(List<LinkConfig> lkConfList) {
+        for (LinkConfig lkc : lkConfList) {
+            String lktype = lkc.getType();
+            switch (lktype) {
+            case PKT_LINK:
+                PktLinkConfig pk = new PktLinkConfig(lkc);
+                for (Link lt : pk.getLinkTupleList()) {
+                    configuredLinks.put(lt, pk);
+                }
+                break;
+            default:
+                throw new NetworkConfigException.UnknownLinkType(lktype,
+                        lkc.getNodeDpid1(), lkc.getNodeDpid2());
+            }
+        }
+    }
+
+    private void validateSwitchConfig(List<SwitchConfig> swConfList) {
+        Set<DeviceId> swDpids = new HashSet<DeviceId>();
+        Set<String> swNames = new HashSet<String>();
+        for (SwitchConfig swc : swConfList) {
+            if (swc.getNodeDpid() == null || swc.getDpid() == null) {
+                throw new NetworkConfigException.DpidNotSpecified(swc.getName());
+            }
+            // ensure both String and DeviceId values of dpid are set
+            if (!swc.getDpid().equals(DeviceId.deviceId(swc.getNodeDpid()))) {
+                throw new NetworkConfigException.SwitchDpidNotConverted(
+                        swc.getName());
+            }
+            if (swc.getName() == null) {
+                throw new NetworkConfigException.NameNotSpecified(swc.getDpid());
+            }
+            if (swc.getType() == null) {
+                throw new NetworkConfigException.SwitchTypeNotSpecified(
+                        swc.getDpid());
+            }
+            if (!swDpids.add(swc.getDpid())) {
+                throw new NetworkConfigException.DuplicateDpid(swc.getDpid());
+            }
+            if (!swNames.add(swc.getName())) {
+                throw new NetworkConfigException.DuplicateName(swc.getName());
+            }
+            // TODO Add more validations
+        }
+    }
+
+    private void validateLinkConfig(List<LinkConfig> lkConfList) {
+        for (LinkConfig lkc : lkConfList) {
+            if (lkc.getNodeDpid1() == null || lkc.getNodeDpid2() == null) {
+                throw new NetworkConfigException.LinkDpidNotSpecified(
+                        lkc.getNodeDpid1(), lkc.getNodeDpid2());
+            }
+            // ensure both String and Long values are set
+            if (!lkc.getDpid1().equals(DeviceId.deviceId(lkc.getNodeDpid1())) ||
+                    !lkc.getDpid2().equals(DeviceId.deviceId(lkc.getNodeDpid2()))) {
+                throw new NetworkConfigException.LinkDpidNotConverted(
+                        lkc.getNodeDpid1(), lkc.getNodeDpid2());
+            }
+            if (lkc.getType() == null) {
+                throw new NetworkConfigException.LinkTypeNotSpecified(
+                        lkc.getNodeDpid1(), lkc.getNodeDpid2());
+            }
+            if (configuredSwitches.get(lkc.getDpid1()) == null) {
+                throw new NetworkConfigException.LinkForUnknownSwitchConfig(
+                        lkc.getNodeDpid1());
+            }
+            if (configuredSwitches.get(lkc.getDpid2()) == null) {
+                throw new NetworkConfigException.LinkForUnknownSwitchConfig(
+                        lkc.getNodeDpid2());
+            }
+            // TODO add more validations
+        }
+
+    }
+
+    private LinkConfig getConfiguredLink(Link linkTuple) {
+        LinkConfig lkc = null;
+        // first try the unidirectional link with the ports assigned
+        lkc = configuredLinks.get(linkTuple);
+        return lkc;
+    }
+
+
+    /**
+     * Initializes the network configuration manager module by
+     * loading and parsing the network configuration file.
+     */
+    public void init() {
+        loadNetworkConfig();
+        configuredSwitches = new ConcurrentHashMap<DeviceId, SwitchConfig>();
+        configuredLinks = new ConcurrentHashMap<Link, LinkConfig>();
+        nameToDpid = new HashMap<String, DeviceId>();
+        parseNetworkConfig();
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigService.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigService.java
new file mode 100644
index 00000000..56855271
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/NetworkConfigService.java
@@ -0,0 +1,256 @@
+package org.onosproject.segmentrouting.config;
+
+import java.util.List;
+
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.segmentrouting.config.NetworkConfig.LinkConfig;
+import org.onosproject.segmentrouting.config.NetworkConfig.SwitchConfig;
+
+/**
+ * Exposes methods to retrieve network configuration.
+ *
+ * TODO: currently only startup-configuration is exposed and such configuration
+ * cannot be changed at runtime. Need to add runtime support for changes to
+ * configuration (via REST/CLI) in future releases.
+ *
+ * TODO: return immutable objects or defensive copies of network config so that
+ * users of this API do not inadvertently or maliciously change network config.
+ *
+ * @deprecated in Drake; see org.onosproject.net.config
+ */
+@Deprecated
+public interface NetworkConfigService {
+
+    /**
+     * Suggests the action to be taken by the caller given the configuration
+     * associated with the queried network-object (eg. switch, link etc.).
+     */
+    enum NetworkConfigState {
+        /**
+         * Associated network object has been configured to not be allowed in
+         * the network.
+         */
+        DENY,
+
+        /**
+         * Associated network object has been configured to be allowed in the
+         * network.
+         */
+        ACCEPT,
+
+        /**
+         * Associated network object has been configured to be allowed in the
+         * network. In addition, there are configured parameters that should be
+         * added to the object.
+         */
+        ACCEPT_ADD,
+    }
+
+    /**
+     * Returns the configuration outcome (accept, deny etc.), and any configured
+     * parameters to the caller, in response to a query for the configuration
+     * associated with a switch.
+     */
+    class SwitchConfigStatus {
+        private NetworkConfigState configState;
+        private SwitchConfig switchConfig;
+        private String msg;
+
+        SwitchConfigStatus(NetworkConfigState configState,
+                SwitchConfig switchConfig, String msg) {
+            this.configState = configState;
+            this.switchConfig = switchConfig;
+            this.msg = msg;
+        }
+
+        SwitchConfigStatus(NetworkConfigState configState,
+                SwitchConfig switchConfig) {
+            this.configState = configState;
+            this.switchConfig = switchConfig;
+            this.msg = "";
+        }
+
+        /**
+         * Returns the configuration state for the switch.
+         *
+         * @return non-null NetworkConfigState
+         */
+        public NetworkConfigState getConfigState() {
+            return configState;
+        }
+
+        /**
+         * Returns the switch configuration, which may be null if no
+         * configuration exists, or if the configuration state disallows the
+         * switch.
+         *
+         * @return SwitchConfig, the switch configuration, or null
+         */
+        public SwitchConfig getSwitchConfig() {
+            return switchConfig;
+        }
+
+        /**
+         * User readable string typically used to specify the reason why a
+         * switch is being disallowed.
+         *
+         * @return A non-null but possibly empty String
+         */
+        public String getMsg() {
+            return msg;
+        }
+
+    }
+
+    /**
+     * Reserved for future use.
+     *
+     * Returns the configuration outcome (accept, deny etc.), and any configured
+     * parameters to the caller, in response to a query for the configuration
+     * associated with a link.
+     */
+    class LinkConfigStatus {
+        private NetworkConfigState configState;
+        private LinkConfig linkConfig;
+        private String msg;
+
+        LinkConfigStatus(NetworkConfigState configState,
+                LinkConfig linkConfig, String msg) {
+            this.configState = configState;
+            this.linkConfig = linkConfig;
+            this.msg = msg;
+        }
+
+        LinkConfigStatus(NetworkConfigState configState,
+                LinkConfig linkConfig) {
+            this.configState = configState;
+            this.linkConfig = linkConfig;
+            this.msg = "";
+        }
+
+        /**
+         * Returns the configuration state for the link.
+         *
+         * @return non-null NetworkConfigState
+         */
+        public NetworkConfigState getConfigState() {
+            return configState;
+        }
+
+        /**
+         * Returns the link configuration, which may be null if no configuration
+         * exists, or if the configuration state disallows the link.
+         *
+         * @return SwitchConfig, the switch configuration, or null
+         */
+        public LinkConfig getLinkConfig() {
+            return linkConfig;
+        }
+
+        /**
+         * User readable string typically used to specify the reason why a link
+         * is being disallowed.
+         *
+         * @return msg A non-null but possibly empty String
+         */
+        public String getMsg() {
+            return msg;
+        }
+
+    }
+
+    /**
+     * Checks the switch configuration (if any) associated with the 'dpid'.
+     * Determines if the switch should be allowed or denied according to
+     * configuration rules.
+     *
+     * The method always returns a non-null SwitchConfigStatus. The enclosed
+     * ConfigState contains the result of the check. The enclosed SwitchConfig
+     * may or may not be null, depending on the outcome of the check.
+     *
+     * @param dpid device id of the switch to be queried
+     * @return SwitchConfigStatus with outcome of check and associated config.
+     */
+    SwitchConfigStatus checkSwitchConfig(DeviceId dpid);
+
+    /**
+     * Reserved for future use.
+     *
+     * Checks the link configuration (if any) associated with the 'link'.
+     * Determines if the link should be allowed or denied according to
+     * configuration rules. Note that the 'link' is a unidirectional link which
+     * checked against configuration that is typically defined for a
+     * bidirectional link. The caller may make a second call if it wishes to
+     * check the 'reverse' direction.
+     *
+     * Also note that the configuration may not specify ports for a given
+     * bidirectional link. In such cases, the configuration applies to all links
+     * between the two switches. This method will check the given 'link' against
+     * such configuration.
+
+     * The method always returns a non-null LinkConfigStatus. The enclosed
+     * ConfigState contains the result of the check. The enclosed LinkConfig may
+     * or may not be null, depending on the outcome of the check.
+     *
+     * @param linkTuple unidirectional link to be queried
+     * @return LinkConfigStatus with outcome of check and associated config.
+     */
+    LinkConfigStatus checkLinkConfig(Link linkTuple);
+
+    /**
+     * Retrieves a list of switches that have been configured, and have been
+     * determined to be 'allowed' in the network, according to configuration
+     * rules.
+     *
+     * Note that it is possible that there are other switches that are allowed
+     * in the network that have NOT been configured. Such switches will not be a
+     * part of the returned list.
+     *
+     * Also note that it is possible that some switches will not be discovered
+     * and the only way the controller can know about these switches is via
+     * configuration. Such switches will be included in this list. It is up to
+     * the caller to determine which SwitchConfig applies to non-discovered
+     * switches.
+     *
+     * @return a non-null List of SwitchConfig which may be empty
+     */
+    List<SwitchConfig> getConfiguredAllowedSwitches();
+
+    /**
+     * Reserved for future use.
+     *
+     * Retrieves a list of links that have been configured, and have been
+     * determined to be 'allowed' in the network, according to configuration
+     * rules.
+     *
+     * Note that it is possible that there are other links that are allowed in
+     * the network that have NOT been configured. Such links will not be a part
+     * of the returned list.
+     *
+     * Also note that it is possible that some links will not be discovered and
+     * the only way the controller can know about these links is via
+     * configuration. Such links will be included in this list. It is up to the
+     * caller to determine which LinkConfig applies to non-discovered links.
+     *
+     * In addition, note that the LinkConfig applies to the configured
+     * bi-directional link, which may or may not have declared ports. The
+     * associated unidirectional LinkTuple can be retrieved from the
+     * getLinkTupleList() method in the LinkConfig object.
+     *
+     * @return a non-null List of LinkConfig which may be empty
+     */
+    List<LinkConfig> getConfiguredAllowedLinks();
+
+    /**
+     * Retrieves the Dpid associated with a 'name' for a configured switch
+     * object. This method does not check of the switches are 'allowed' by
+     * config.
+     *
+     * @param name device name
+     * @return the Dpid corresponding to a given 'name', or null if no
+     *         configured switch was found for the given 'name'.
+     */
+    DeviceId getDpidForName(String name);
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/PktLinkConfig.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/PktLinkConfig.java
new file mode 100644
index 00000000..c66ac3c7
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/PktLinkConfig.java
@@ -0,0 +1,144 @@
+package org.onosproject.segmentrouting.config;
+
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.onosproject.net.Link;
+import org.onosproject.segmentrouting.config.NetworkConfig.LinkConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.databind.JsonNode;
+
+/**
+ * Reserved for future use.
+ * Configuration for a link between two packet-switches.
+ */
+public class PktLinkConfig extends LinkConfig {
+    protected static final Logger log = LoggerFactory
+            .getLogger(PktLinkConfig.class);
+    private int port1;
+    private int port2;
+    private String nodeName1;
+    private String nodeName2;
+    private List<Link> linkTupleList;
+
+    public PktLinkConfig(LinkConfig lkc) {
+        nodeDpid1 = lkc.getNodeDpid1();
+        nodeDpid2 = lkc.getNodeDpid2();
+        dpid1 = lkc.getDpid1();
+        dpid2 = lkc.getDpid2();
+        type = lkc.getType();
+        allowed = lkc.isAllowed();
+        params = lkc.getParams();
+        publishAttributes = new ConcurrentHashMap<String, String>();
+        parseParams();
+        validateParams();
+        setPublishAttributes();
+    }
+
+    // ********************
+    // Packet Link Configuration
+    // ********************
+
+    public int getPort1() {
+        return port1;
+    }
+
+    public void setPort1(int port1) {
+        this.port1 = port1;
+    }
+
+    public int getPort2() {
+        return port2;
+    }
+
+    public void setPort2(int port2) {
+        this.port2 = port2;
+    }
+
+    public String getNodeName1() {
+        return nodeName1;
+    }
+
+    public void setNodeName1(String nodeName1) {
+        this.nodeName1 = nodeName1;
+    }
+
+    public String getNodeName2() {
+        return nodeName2;
+    }
+
+    public void setNodeName2(String nodeName2) {
+        this.nodeName2 = nodeName2;
+    }
+
+    /**
+     * Returns the two unidirectional links corresponding to the packet-link
+     * configuration. It is possible that the ports in the LinkTuple have
+     * portnumber '0', implying that the configuration applies to all links
+     * between the two switches.
+     *
+     * @return a list of LinkTuple with exactly 2 unidirectional links
+     */
+    public List<Link> getLinkTupleList() {
+        return linkTupleList;
+    }
+
+    private void setPublishAttributes() {
+
+    }
+
+    private void parseParams() {
+        if (params == null) {
+            throw new PktLinkParamsNotSpecified(nodeDpid1, nodeDpid2);
+        }
+        Set<Entry<String, JsonNode>> m = params.entrySet();
+        for (Entry<String, JsonNode> e : m) {
+            String key = e.getKey();
+            JsonNode j = e.getValue();
+            if (key.equals("nodeName1")) {
+                setNodeName1(j.asText());
+            } else if (key.equals("nodeName2")) {
+                setNodeName2(j.asText());
+            } else if (key.equals("port1")) {
+                setPort1(j.asInt());
+            } else if (key.equals("port2")) {
+                setPort2(j.asInt());
+            } else {
+                throw new UnknownPktLinkConfig(key, nodeDpid1, nodeDpid2);
+            }
+        }
+    }
+
+    private void validateParams() {
+        // TODO - wrong-names, duplicate links,
+        // duplicate use of port, is switch-allowed for which link is allowed?
+        // valid port numbers
+    }
+
+    public static class PktLinkParamsNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = 6247582323691265513L;
+
+        public PktLinkParamsNotSpecified(String dpidA, String dpidB) {
+            super();
+            log.error("Params required for packet link - not specified "
+                    + "for link between switch1:{} and switch2:{}",
+                    dpidA, dpidB);
+        }
+    }
+
+    public static class UnknownPktLinkConfig extends RuntimeException {
+        private static final long serialVersionUID = -5750132094884129179L;
+
+        public UnknownPktLinkConfig(String key, String dpidA, String dpidB) {
+            super();
+            log.error("Unknown packet-link config {} for link between"
+                    + " dpid1: {} and dpid2: {}", key,
+                    dpidA, dpidB);
+        }
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/SegmentRouterConfig.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/SegmentRouterConfig.java
new file mode 100644
index 00000000..4775c77f
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/SegmentRouterConfig.java
@@ -0,0 +1,430 @@
+package org.onosproject.segmentrouting.config;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.onosproject.net.DeviceId;
+import org.onosproject.segmentrouting.config.NetworkConfig.SwitchConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+/**
+ * Manages additional configuration for switches configured as Segment Routers.
+ */
+public class SegmentRouterConfig extends SwitchConfig {
+    protected static final Logger log = LoggerFactory
+            .getLogger(SegmentRouterConfig.class);
+    private String routerIp;
+    private String routerMac;
+    private int nodeSid;
+    private boolean isEdgeRouter;
+    private List<AdjacencySid> adjacencySids;
+    private List<Subnet> subnets;
+
+    public static final String ROUTER_IP = "routerIp";
+    public static final String ROUTER_MAC = "routerMac";
+    public static final String NODE_SID = "nodeSid";
+    public static final String ADJACENCY_SIDS = "adjacencySids";
+    public static final String SUBNETS = "subnets";
+    public static final String ISEDGE = "isEdgeRouter";
+    private static final int SRGB_MAX = 1000;
+
+    /**
+     * Parses and validates the additional configuration parameters applicable
+     * to segment routers.
+     *
+     * @param swc switch configuration
+     */
+    public SegmentRouterConfig(SwitchConfig swc) {
+        this.setName(swc.getName());
+        this.setDpid(swc.getDpid());
+        this.setType(swc.getType());
+        this.setLatitude(swc.getLatitude());
+        this.setLongitude(swc.getLongitude());
+        this.setParams(swc.getParams());
+        this.setAllowed(swc.isAllowed());
+        publishAttributes = new ConcurrentHashMap<String, String>();
+        adjacencySids = new ArrayList<AdjacencySid>();
+        subnets = new ArrayList<Subnet>();
+        parseParams();
+        validateParams();
+        setPublishAttributes();
+    }
+
+    /**
+     * Returns the configured segment router IP address.
+     *
+     * @return ip address in string format
+     */
+    public String getRouterIp() {
+        return routerIp;
+    }
+
+    public void setRouterIp(String routerIp) {
+        this.routerIp = routerIp;
+    }
+
+    /**
+     * Returns the configured segment router mac address.
+     *
+     * @return mac address in string format
+     */
+    public String getRouterMac() {
+        return routerMac;
+    }
+
+    public void setRouterMac(String routerMac) {
+        this.routerMac = routerMac;
+    }
+
+    /**
+     * Returns the configured sID for a segment router.
+     *
+     * @return segment identifier
+     */
+    public int getNodeSid() {
+        return nodeSid;
+    }
+
+    public void setNodeSid(int nodeSid) {
+        this.nodeSid = nodeSid;
+    }
+
+    /**
+     * Returns the flag that indicates the configured segment router
+     * is edge or backbone router.
+     *
+     * @return boolean
+     */
+    public boolean isEdgeRouter() {
+        return isEdgeRouter;
+    }
+
+    public void setIsEdgeRouter(boolean isEdge) {
+        this.isEdgeRouter = isEdge;
+    }
+
+    /**
+     * Class representing segment router adjacency identifier.
+     */
+    public static class AdjacencySid {
+        private int adjSid;
+        private List<Integer> ports;
+
+        public AdjacencySid(int adjSid, List<Integer> ports) {
+            this.ports = ports;
+            this.adjSid = adjSid;
+        }
+
+        /**
+         * Returns the list of ports part of a segment
+         * router adjacency identifier.
+         *
+         * @return list of integers
+         */
+        public List<Integer> getPorts() {
+            return ports;
+        }
+
+        public void setPorts(List<Integer> ports) {
+            this.ports = ports;
+        }
+
+        /**
+         * Returns the configured adjacency id of a segment router.
+         *
+         * @return integer
+         */
+        public int getAdjSid() {
+            return adjSid;
+        }
+
+        public void setAdjSid(int adjSid) {
+            this.adjSid = adjSid;
+        }
+    }
+
+    /**
+     * Returns the configured adjacent segment IDs for a segment router.
+     *
+     * @return list of adjacency identifier
+     */
+    public List<AdjacencySid> getAdjacencySids() {
+        return adjacencySids;
+    }
+
+    public void setAdjacencySids(List<AdjacencySid> adjacencySids) {
+        this.adjacencySids = adjacencySids;
+    }
+
+    /**
+     * Class representing a subnet attached to a segment router.
+     */
+    public static class Subnet {
+        private int portNo;
+        private String subnetIp;
+
+        public Subnet(int portNo, String subnetIp) {
+            this.portNo = portNo;
+            this.subnetIp = subnetIp;
+        }
+
+        /**
+         * Returns the port number of segment router on
+         * which subnet is attached.
+         *
+         * @return integer
+         */
+        public int getPortNo() {
+            return portNo;
+        }
+
+        public void setPortNo(int portNo) {
+            this.portNo = portNo;
+        }
+
+        /**
+         * Returns the configured subnet address.
+         *
+         * @return subnet ip address in string format
+         */
+        public String getSubnetIp() {
+            return subnetIp;
+        }
+
+        public void setSubnetIp(String subnetIp) {
+            this.subnetIp = subnetIp;
+        }
+    }
+
+    /**
+     * Returns the configured subnets for a segment router.
+     *
+     * @return list of subnets
+     */
+    public List<Subnet> getSubnets() {
+        return subnets;
+    }
+
+    public void setSubnets(List<Subnet> subnets) {
+        this.subnets = subnets;
+    }
+
+    // ********************
+    // Helper methods
+    // ********************
+
+    private void parseParams() {
+        if (params == null) {
+            throw new NetworkConfigException.ParamsNotSpecified(name);
+        }
+
+        Set<Entry<String, JsonNode>> m = params.entrySet();
+        for (Entry<String, JsonNode> e : m) {
+            String key = e.getKey();
+            JsonNode j = e.getValue();
+            if (key.equals("routerIp")) {
+                setRouterIp(j.asText());
+            } else if (key.equals("routerMac")) {
+                setRouterMac(j.asText());
+            } else if (key.equals("nodeSid")) {
+                setNodeSid(j.asInt());
+            } else if (key.equals("isEdgeRouter")) {
+                setIsEdgeRouter(j.asBoolean());
+            } else if (key.equals("adjacencySids") || key.equals("subnets")) {
+                getInnerParams(j, key);
+            } else {
+                throw new UnknownSegmentRouterConfig(key, dpid);
+            }
+        }
+    }
+
+    private void getInnerParams(JsonNode j, String innerParam) {
+        Iterator<JsonNode> innerList = j.elements();
+        while (innerList.hasNext()) {
+            Iterator<Entry<String, JsonNode>> f = innerList.next().fields();
+            int portNo = -1;
+            int adjSid = -1;
+            String subnetIp = null;
+            List<Integer> ports = null;
+            while (f.hasNext()) {
+                Entry<String, JsonNode> fe = f.next();
+                if (fe.getKey().equals("portNo")) {
+                    portNo = fe.getValue().asInt();
+                } else if (fe.getKey().equals("adjSid")) {
+                    adjSid = fe.getValue().asInt();
+                } else if (fe.getKey().equals("subnetIp")) {
+                    subnetIp = fe.getValue().asText();
+                } else if (fe.getKey().equals("ports")) {
+                    if (fe.getValue().isArray()) {
+                        Iterator<JsonNode> i = fe.getValue().elements();
+                        ports = new ArrayList<Integer>();
+                        while (i.hasNext()) {
+                            ports.add(i.next().asInt());
+                        }
+                    }
+                } else {
+                    throw new UnknownSegmentRouterConfig(fe.getKey(), dpid);
+                }
+            }
+            if (innerParam.equals("adjacencySids")) {
+                AdjacencySid ads = new AdjacencySid(adjSid, ports);
+                adjacencySids.add(ads);
+            } else {
+                Subnet sip = new Subnet(portNo, subnetIp);
+                subnets.add(sip);
+            }
+        }
+    }
+
+    private void validateParams() {
+        if (routerIp == null) {
+            throw new IpNotSpecified(dpid);
+        }
+        if (routerMac == null) {
+            throw new MacNotSpecified(dpid);
+        }
+        if (isEdgeRouter && subnets.isEmpty()) {
+            throw new SubnetNotSpecifiedInEdgeRouter(dpid);
+        }
+        if (!isEdgeRouter && !subnets.isEmpty()) {
+            throw new SubnetSpecifiedInBackboneRouter(dpid);
+        }
+        if (nodeSid > SRGB_MAX) {
+            throw new NodeLabelNotInSRGB(nodeSid, dpid);
+        }
+        for (AdjacencySid as : adjacencySids) {
+            int label = as.getAdjSid();
+            List<Integer> plist = as.getPorts();
+            if (label <= SRGB_MAX) {
+                throw new AdjacencyLabelInSRGB(label, dpid);
+            }
+            if (plist.size() <= 1) {
+                throw new AdjacencyLabelNotEnoughPorts(label, dpid);
+            }
+        }
+
+
+        // TODO more validations
+    }
+
+    /**
+     * Setting publishAttributes implies that this is the configuration that
+     * will be added to Topology.Switch object before it is published on the
+     * channel to other controller instances.
+     */
+    private void setPublishAttributes() {
+        publishAttributes.put(ROUTER_IP, routerIp);
+        publishAttributes.put(ROUTER_MAC, routerMac);
+        publishAttributes.put(NODE_SID, String.valueOf(nodeSid));
+        publishAttributes.put(ISEDGE, String.valueOf(isEdgeRouter));
+        ObjectMapper mapper = new ObjectMapper();
+        try {
+            publishAttributes.put(ADJACENCY_SIDS,
+                    mapper.writeValueAsString(adjacencySids));
+            publishAttributes.put(SUBNETS,
+                    mapper.writeValueAsString(subnets));
+        } catch (JsonProcessingException e) {
+            log.error("Error while writing SR config: {}", e.getCause());
+        } catch (IOException e) {
+            log.error("Error while writing SR config: {}", e.getCause());
+        }
+    }
+
+    // ********************
+    // Exceptions
+    // ********************
+
+    public static class IpNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -3001502553646331686L;
+
+        public IpNotSpecified(DeviceId dpid) {
+            super();
+            log.error("Router IP address not specified for SR config dpid:{}",
+                    dpid);
+        }
+    }
+
+    public static class MacNotSpecified extends RuntimeException {
+        private static final long serialVersionUID = -5850132094884129179L;
+
+        public MacNotSpecified(DeviceId dpid) {
+            super();
+            log.error("Router Mac address not specified for SR config dpid:{}",
+                    dpid);
+        }
+    }
+
+    public static class UnknownSegmentRouterConfig extends RuntimeException {
+        private static final long serialVersionUID = -5750132094884129179L;
+
+        public UnknownSegmentRouterConfig(String key, DeviceId dpid) {
+            super();
+            log.error("Unknown Segment Router config {} in dpid: {}", key,
+                    dpid);
+        }
+    }
+
+    public static class SubnetNotSpecifiedInEdgeRouter extends RuntimeException {
+        private static final long serialVersionUID = -5855458472668581268L;
+
+        public SubnetNotSpecifiedInEdgeRouter(DeviceId dpid) {
+            super();
+            log.error("Subnet was not specified for edge router in dpid: {}",
+                    dpid);
+        }
+    }
+
+    public static class SubnetSpecifiedInBackboneRouter extends RuntimeException {
+        private static final long serialVersionUID = 1L;
+
+        public SubnetSpecifiedInBackboneRouter(DeviceId dpid) {
+            super();
+            log.error("Subnet was specified in backbone router in dpid: {}",
+                    dpid);
+        }
+    }
+
+    public static class NodeLabelNotInSRGB extends RuntimeException {
+        private static final long serialVersionUID = -8482670903748519526L;
+
+        public NodeLabelNotInSRGB(int label, DeviceId dpid) {
+            super();
+            log.error("Node sif {} specified in not in global label-base "
+                    + "in dpid: {}", label,
+                    dpid);
+        }
+    }
+
+    public static class AdjacencyLabelInSRGB extends RuntimeException {
+        private static final long serialVersionUID = -8482670903748519526L;
+
+        public AdjacencyLabelInSRGB(int label, DeviceId dpid) {
+            super();
+            log.error("Adjaceny label {} specified from global label-base "
+                    + "in dpid: {}", label,
+                    dpid);
+        }
+    }
+
+    public static class AdjacencyLabelNotEnoughPorts extends RuntimeException {
+        private static final long serialVersionUID = -8482670903748519526L;
+
+        public AdjacencyLabelNotEnoughPorts(int label, DeviceId dpid) {
+            super();
+            log.error("Adjaceny label {} must be specified for at least 2 ports. "
+                    + "Adjacency labels for single ports are auto-generated "
+                    + "in dpid: {}", label,
+                    dpid);
+        }
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/package-info.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/package-info.java
new file mode 100644
index 00000000..fdae9c9e
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/config/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Segment routing network configuration mechanism.
+ */
+package org.onosproject.segmentrouting.config;
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultEdgeGroupHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultEdgeGroupHandler.java
new file mode 100644
index 00000000..41cf8acc
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultEdgeGroupHandler.java
@@ -0,0 +1,180 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.link.LinkService;
+import org.onosproject.store.service.EventuallyConsistentMap;
+
+/**
+ * Default ECMP group handler creation module for an edge device.
+ * This component creates a set of ECMP groups for every neighbor
+ * that this device is connected to.
+ * For example, consider a network of 4 devices: D0 (Segment ID: 100),
+ * D1 (Segment ID: 101), D2 (Segment ID: 102) and D3 (Segment ID: 103),
+ * where D0 and D3 are edge devices and D1 and D2 are transit devices.
+ * Assume device D0 is connected to 2 neighbors (D1 and D2 ).
+ * The following groups will be created in D0:
+ * 1) all ports to D1 + with no label push,
+ * 2) all ports to D1 + with label 102 pushed,
+ * 3) all ports to D1 + with label 103 pushed,
+ * 4) all ports to D2 + with no label push,
+ * 5) all ports to D2 + with label 101 pushed,
+ * 6) all ports to D2 + with label 103 pushed,
+ * 7) all ports to D1 and D2 + with label 103 pushed
+ */
+public class DefaultEdgeGroupHandler extends DefaultGroupHandler {
+
+    protected DefaultEdgeGroupHandler(DeviceId deviceId,
+                                  ApplicationId appId,
+                                  DeviceProperties config,
+                                  LinkService linkService,
+                                  FlowObjectiveService flowObjService,
+                                  EventuallyConsistentMap<
+                                  NeighborSetNextObjectiveStoreKey,
+                                  Integer> nsNextObjStore) {
+        super(deviceId, appId, config, linkService, flowObjService, nsNextObjStore);
+    }
+
+    @Override
+    public void createGroups() {
+        log.debug("Creating default groups "
+                + "for edge device {}", deviceId);
+        Set<DeviceId> neighbors = devicePortMap.keySet();
+        if (neighbors == null || neighbors.isEmpty()) {
+            return;
+        }
+
+        // Create all possible Neighbor sets from this router
+        Set<Set<DeviceId>> powerSet = getPowerSetOfNeighbors(neighbors);
+        log.trace("createGroupsAtEdgeRouter: The size of neighbor powerset "
+                + "for sw {} is {}", deviceId, powerSet.size());
+        Set<NeighborSet> nsSet = new HashSet<NeighborSet>();
+        for (Set<DeviceId> combo : powerSet) {
+            if (combo.isEmpty()) {
+                continue;
+            }
+            List<Integer> groupSegmentIds =
+                    getSegmentIdsTobePairedWithNeighborSet(combo);
+            for (Integer sId : groupSegmentIds) {
+                NeighborSet ns = new NeighborSet(combo, sId);
+                log.trace("createGroupsAtEdgeRouter: sw {} "
+                        + "combo {} sId {} ns {}",
+                        deviceId, combo, sId, ns);
+                nsSet.add(ns);
+            }
+        }
+        log.trace("createGroupsAtEdgeRouter: The neighborset "
+                + "with label for sw {} is {}",
+                deviceId, nsSet);
+
+        createGroupsFromNeighborsets(nsSet);
+    }
+
+    @Override
+    protected void newNeighbor(Link newNeighborLink) {
+        log.debug("New Neighbor: Updating groups "
+                + "for edge device {}", deviceId);
+        // Recompute neighbor power set
+        addNeighborAtPort(newNeighborLink.dst().deviceId(),
+                          newNeighborLink.src().port());
+        // Compute new neighbor sets due to the addition of new neighbor
+        Set<NeighborSet> nsSet = computeImpactedNeighborsetForPortEvent(
+                                             newNeighborLink.dst().deviceId(),
+                                             devicePortMap.keySet());
+        createGroupsFromNeighborsets(nsSet);
+    }
+
+    @Override
+    protected void newPortToExistingNeighbor(Link newNeighborLink) {
+        /*log.debug("New port to existing neighbor: Updating "
+                + "groups for edge device {}", deviceId);
+        addNeighborAtPort(newNeighborLink.dst().deviceId(),
+                          newNeighborLink.src().port());
+        Set<NeighborSet> nsSet = computeImpactedNeighborsetForPortEvent(
+                                              newNeighborLink.dst().deviceId(),
+                                              devicePortMap.keySet());
+        for (NeighborSet ns : nsSet) {
+            // Create the new bucket to be updated
+            TrafficTreatment.Builder tBuilder =
+                    DefaultTrafficTreatment.builder();
+            tBuilder.setOutput(newNeighborLink.src().port())
+                    .setEthDst(deviceConfig.getDeviceMac(
+                          newNeighborLink.dst().deviceId()))
+                    .setEthSrc(nodeMacAddr);
+            if (ns.getEdgeLabel() != NeighborSet.NO_EDGE_LABEL) {
+                tBuilder.pushMpls()
+                        .setMpls(MplsLabel.
+                                 mplsLabel(ns.getEdgeLabel()));
+            }
+
+            Integer nextId = deviceNextObjectiveIds.get(ns);
+            if (nextId != null) {
+                NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                        .builder().withId(nextId)
+                        .withType(NextObjective.Type.HASHED).fromApp(appId);
+
+                nextObjBuilder.addTreatment(tBuilder.build());
+
+                NextObjective nextObjective = nextObjBuilder.add();
+                flowObjectiveService.next(deviceId, nextObjective);
+            }
+        }*/
+    }
+
+    @Override
+    protected Set<NeighborSet> computeImpactedNeighborsetForPortEvent(
+                                            DeviceId impactedNeighbor,
+                                            Set<DeviceId> updatedNeighbors) {
+        Set<Set<DeviceId>> powerSet = getPowerSetOfNeighbors(updatedNeighbors);
+
+        Set<DeviceId> tmp = new HashSet<DeviceId>();
+        tmp.addAll(updatedNeighbors);
+        tmp.remove(impactedNeighbor);
+        Set<Set<DeviceId>> tmpPowerSet = getPowerSetOfNeighbors(tmp);
+
+        // Compute the impacted neighbor sets
+        powerSet.removeAll(tmpPowerSet);
+
+        Set<NeighborSet> nsSet = new HashSet<NeighborSet>();
+        for (Set<DeviceId> combo : powerSet) {
+            if (combo.isEmpty()) {
+                continue;
+            }
+            List<Integer> groupSegmentIds =
+                    getSegmentIdsTobePairedWithNeighborSet(combo);
+            for (Integer sId : groupSegmentIds) {
+                NeighborSet ns = new NeighborSet(combo, sId);
+                log.trace("computeImpactedNeighborsetForPortEvent: sw {} "
+                        + "combo {} sId {} ns {}",
+                        deviceId, combo, sId, ns);
+                nsSet.add(ns);
+            }
+        }
+        log.trace("computeImpactedNeighborsetForPortEvent: The neighborset "
+                + "with label for sw {} is {}",
+                deviceId, nsSet);
+        return nsSet;
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultGroupHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultGroupHandler.java
new file mode 100644
index 00000000..a43a0f09
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultGroupHandler.java
@@ -0,0 +1,539 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.slf4j.LoggerFactory.getLogger;
+
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Random;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import org.onlab.packet.MacAddress;
+import org.onlab.packet.MplsLabel;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flowobjective.DefaultNextObjective;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.flowobjective.NextObjective;
+import org.onosproject.net.flowobjective.Objective;
+import org.onosproject.net.flowobjective.ObjectiveContext;
+import org.onosproject.net.flowobjective.ObjectiveError;
+import org.onosproject.net.group.DefaultGroupKey;
+import org.onosproject.net.group.GroupKey;
+import org.onosproject.net.link.LinkService;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.slf4j.Logger;
+
+/**
+ * Default ECMP group handler creation module. This component creates a set of
+ * ECMP groups for every neighbor that this device is connected to based on
+ * whether the current device is an edge device or a transit device.
+ */
+public class DefaultGroupHandler {
+    protected static final Logger log = getLogger(DefaultGroupHandler.class);
+
+    protected final DeviceId deviceId;
+    protected final ApplicationId appId;
+    protected final DeviceProperties deviceConfig;
+    protected final List<Integer> allSegmentIds;
+    protected final int nodeSegmentId;
+    protected final boolean isEdgeRouter;
+    protected final MacAddress nodeMacAddr;
+    protected LinkService linkService;
+    protected FlowObjectiveService flowObjectiveService;
+
+    protected HashMap<DeviceId, Set<PortNumber>> devicePortMap = new HashMap<>();
+    protected HashMap<PortNumber, DeviceId> portDeviceMap = new HashMap<>();
+    //protected HashMap<NeighborSet, Integer> deviceNextObjectiveIds =
+    //        new HashMap<NeighborSet, Integer>();
+    protected EventuallyConsistentMap<
+        NeighborSetNextObjectiveStoreKey, Integer> nsNextObjStore = null;
+    protected Random rand = new Random();
+
+    protected KryoNamespace.Builder kryo = new KryoNamespace.Builder()
+            .register(URI.class).register(HashSet.class)
+            .register(DeviceId.class).register(PortNumber.class)
+            .register(NeighborSet.class).register(PolicyGroupIdentifier.class)
+            .register(PolicyGroupParams.class)
+            .register(GroupBucketIdentifier.class)
+            .register(GroupBucketIdentifier.BucketOutputType.class);
+
+    protected DefaultGroupHandler(DeviceId deviceId, ApplicationId appId,
+                                  DeviceProperties config,
+                                  LinkService linkService,
+                                  FlowObjectiveService flowObjService,
+                                  EventuallyConsistentMap<
+                                  NeighborSetNextObjectiveStoreKey,
+                                  Integer> nsNextObjStore) {
+        this.deviceId = checkNotNull(deviceId);
+        this.appId = checkNotNull(appId);
+        this.deviceConfig = checkNotNull(config);
+        this.linkService = checkNotNull(linkService);
+        allSegmentIds = checkNotNull(config.getAllDeviceSegmentIds());
+        nodeSegmentId = config.getSegmentId(deviceId);
+        isEdgeRouter = config.isEdgeDevice(deviceId);
+        nodeMacAddr = checkNotNull(config.getDeviceMac(deviceId));
+        this.flowObjectiveService = flowObjService;
+        this.nsNextObjStore = nsNextObjStore;
+
+        populateNeighborMaps();
+    }
+
+    /**
+     * Creates a group handler object based on the type of device. If device is
+     * of edge type it returns edge group handler, else it returns transit group
+     * handler.
+     *
+     * @param deviceId device identifier
+     * @param appId application identifier
+     * @param config interface to retrieve the device properties
+     * @param linkService link service object
+     * @param flowObjService flow objective service object
+     * @param nsNextObjStore next objective store map
+     * @return default group handler type
+     */
+    public static DefaultGroupHandler createGroupHandler(DeviceId deviceId,
+                                                         ApplicationId appId,
+                                                         DeviceProperties config,
+                                                         LinkService linkService,
+                                                         FlowObjectiveService flowObjService,
+                                                         EventuallyConsistentMap<NeighborSetNextObjectiveStoreKey,
+                                                                 Integer> nsNextObjStore) {
+        if (config.isEdgeDevice(deviceId)) {
+            return new DefaultEdgeGroupHandler(deviceId, appId, config,
+                                               linkService,
+                                               flowObjService,
+                                               nsNextObjStore);
+        } else {
+            return new DefaultTransitGroupHandler(deviceId, appId, config,
+                                                  linkService,
+                                                  flowObjService,
+                                                  nsNextObjStore);
+        }
+    }
+
+    /**
+     * Creates the auto created groups for this device based on the current
+     * snapshot of the topology.
+     */
+    // Empty implementations to be overridden by derived classes
+    public void createGroups() {
+    }
+
+    /**
+     * Performs group creation or update procedures when a new link is
+     * discovered on this device.
+     *
+     * @param newLink new neighbor link
+     */
+    public void linkUp(Link newLink) {
+
+        if (newLink.type() != Link.Type.DIRECT) {
+            log.warn("linkUp: unknown link type");
+            return;
+        }
+
+        if (!newLink.src().deviceId().equals(deviceId)) {
+            log.warn("linkUp: deviceId{} doesn't match with link src{}",
+                     deviceId, newLink.src().deviceId());
+            return;
+        }
+
+        log.debug("Device {} linkUp at local port {} to neighbor {}", deviceId,
+                  newLink.src().port(), newLink.dst().deviceId());
+        addNeighborAtPort(newLink.dst().deviceId(),
+                          newLink.src().port());
+        /*if (devicePortMap.get(newLink.dst().deviceId()) == null) {
+            // New Neighbor
+            newNeighbor(newLink);
+        } else {
+            // Old Neighbor
+            newPortToExistingNeighbor(newLink);
+        }*/
+        Set<NeighborSet> nsSet = nsNextObjStore.keySet()
+                .stream()
+                .filter((nsStoreEntry) -> (nsStoreEntry.deviceId().equals(deviceId)))
+                .map((nsStoreEntry) -> (nsStoreEntry.neighborSet()))
+                .filter((ns) -> (ns.getDeviceIds()
+                        .contains(newLink.dst().deviceId())))
+                .collect(Collectors.toSet());
+        log.trace("linkUp: nsNextObjStore contents for device {}:",
+                deviceId,
+                nsSet);
+        for (NeighborSet ns : nsSet) {
+            // Create the new bucket to be updated
+            TrafficTreatment.Builder tBuilder =
+                    DefaultTrafficTreatment.builder();
+            tBuilder.setOutput(newLink.src().port())
+                    .setEthDst(deviceConfig.getDeviceMac(
+                          newLink.dst().deviceId()))
+                    .setEthSrc(nodeMacAddr);
+            if (ns.getEdgeLabel() != NeighborSet.NO_EDGE_LABEL) {
+                tBuilder.pushMpls()
+                        .setMpls(MplsLabel.
+                                 mplsLabel(ns.getEdgeLabel()));
+            }
+
+            Integer nextId = nsNextObjStore.
+                    get(new NeighborSetNextObjectiveStoreKey(deviceId, ns));
+            if (nextId != null) {
+                NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                        .builder().withId(nextId)
+                        .withType(NextObjective.Type.HASHED).fromApp(appId);
+
+                nextObjBuilder.addTreatment(tBuilder.build());
+
+                log.debug("linkUp in device {}: Adding Bucket "
+                        + "with Port {} to next object id {}",
+                        deviceId,
+                        newLink.src().port(),
+                        nextId);
+                NextObjective nextObjective = nextObjBuilder.
+                        add(new SRNextObjectiveContext(deviceId));
+                flowObjectiveService.next(deviceId, nextObjective);
+            }
+        }
+    }
+
+    /**
+     * Performs group recovery procedures when a port goes down on this device.
+     *
+     * @param port port number that has gone down
+     */
+    public void portDown(PortNumber port) {
+        if (portDeviceMap.get(port) == null) {
+            log.warn("portDown: unknown port");
+            return;
+        }
+        log.debug("Device {} portDown {} to neighbor {}", deviceId, port,
+                  portDeviceMap.get(port));
+        /*Set<NeighborSet> nsSet = computeImpactedNeighborsetForPortEvent(portDeviceMap
+                                                                                .get(port),
+                                                                        devicePortMap
+                                                                                .keySet());*/
+        Set<NeighborSet> nsSet = nsNextObjStore.keySet()
+                .stream()
+                .filter((nsStoreEntry) -> (nsStoreEntry.deviceId().equals(deviceId)))
+                .map((nsStoreEntry) -> (nsStoreEntry.neighborSet()))
+                .filter((ns) -> (ns.getDeviceIds()
+                        .contains(portDeviceMap.get(port))))
+                .collect(Collectors.toSet());
+        log.trace("portDown: nsNextObjStore contents for device {}:",
+                  deviceId,
+                  nsSet);
+        for (NeighborSet ns : nsSet) {
+            // Create the bucket to be removed
+            TrafficTreatment.Builder tBuilder = DefaultTrafficTreatment
+                    .builder();
+            tBuilder.setOutput(port)
+                    .setEthDst(deviceConfig.getDeviceMac(portDeviceMap
+                                       .get(port))).setEthSrc(nodeMacAddr);
+            if (ns.getEdgeLabel() != NeighborSet.NO_EDGE_LABEL) {
+                tBuilder.pushMpls().setMpls(MplsLabel.mplsLabel(ns
+                                                    .getEdgeLabel()));
+            }
+
+            Integer nextId = nsNextObjStore.
+                    get(new NeighborSetNextObjectiveStoreKey(deviceId, ns));
+            if (nextId != null) {
+                NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                        .builder().withType(NextObjective.Type.SIMPLE).withId(nextId).fromApp(appId);
+
+                nextObjBuilder.addTreatment(tBuilder.build());
+
+                log.debug("portDown in device {}: Removing Bucket "
+                        + "with Port {} to next object id {}",
+                        deviceId,
+                        port,
+                        nextId);
+                NextObjective nextObjective = nextObjBuilder.
+                        remove(new SRNextObjectiveContext(deviceId));
+
+                flowObjectiveService.next(deviceId, nextObjective);
+            }
+
+        }
+
+        devicePortMap.get(portDeviceMap.get(port)).remove(port);
+        portDeviceMap.remove(port);
+    }
+
+    /**
+     * Returns the next objective associated with the neighborset.
+     * If there is no next objective for this neighborset, this API
+     * would create a next objective and return.
+     *
+     * @param ns neighborset
+     * @return int if found or -1
+     */
+    public int getNextObjectiveId(NeighborSet ns) {
+        Integer nextId = nsNextObjStore.
+                get(new NeighborSetNextObjectiveStoreKey(deviceId, ns));
+        if (nextId == null) {
+            log.trace("getNextObjectiveId in device{}: Next objective id "
+                    + "not found for {} and creating", deviceId, ns);
+            log.trace("getNextObjectiveId: nsNextObjStore contents for device {}: {}",
+                      deviceId,
+                      nsNextObjStore.entrySet()
+                      .stream()
+                      .filter((nsStoreEntry) ->
+                      (nsStoreEntry.getKey().deviceId().equals(deviceId)))
+                      .collect(Collectors.toList()));
+            createGroupsFromNeighborsets(Collections.singleton(ns));
+            nextId = nsNextObjStore.
+                    get(new NeighborSetNextObjectiveStoreKey(deviceId, ns));
+            if (nextId == null) {
+                log.warn("getNextObjectiveId: unable to create next objective");
+                return -1;
+            } else {
+                log.debug("getNextObjectiveId in device{}: Next objective id {} "
+                    + "created for {}", deviceId, nextId.intValue(), ns);
+            }
+        } else {
+            log.trace("getNextObjectiveId in device{}: Next objective id {} "
+                    + "found for {}", deviceId, nextId.intValue(), ns);
+        }
+        return nextId.intValue();
+    }
+
+    /**
+     * Checks if the next objective ID (group) for the neighbor set exists or not.
+     *
+     * @param ns neighbor set to check
+     * @return true if it exists, false otherwise
+     */
+    public boolean hasNextObjectiveId(NeighborSet ns) {
+        Integer nextId = nsNextObjStore.
+                get(new NeighborSetNextObjectiveStoreKey(deviceId, ns));
+        if (nextId == null) {
+            return false;
+        }
+
+        return true;
+    }
+
+    // Empty implementation
+    protected void newNeighbor(Link newLink) {
+    }
+
+    // Empty implementation
+    protected void newPortToExistingNeighbor(Link newLink) {
+    }
+
+    // Empty implementation
+    protected Set<NeighborSet>
+        computeImpactedNeighborsetForPortEvent(DeviceId impactedNeighbor,
+                                               Set<DeviceId> updatedNeighbors) {
+        return null;
+    }
+
+    private void populateNeighborMaps() {
+        Set<Link> outgoingLinks = linkService.getDeviceEgressLinks(deviceId);
+        for (Link link : outgoingLinks) {
+            if (link.type() != Link.Type.DIRECT) {
+                continue;
+            }
+            addNeighborAtPort(link.dst().deviceId(), link.src().port());
+        }
+    }
+
+    protected void addNeighborAtPort(DeviceId neighborId,
+                                     PortNumber portToNeighbor) {
+        // Update DeviceToPort database
+        log.debug("Device {} addNeighborAtPort: neighbor {} at port {}",
+                  deviceId, neighborId, portToNeighbor);
+        if (devicePortMap.get(neighborId) != null) {
+            devicePortMap.get(neighborId).add(portToNeighbor);
+        } else {
+            Set<PortNumber> ports = new HashSet<PortNumber>();
+            ports.add(portToNeighbor);
+            devicePortMap.put(neighborId, ports);
+        }
+
+        // Update portToDevice database
+        if (portDeviceMap.get(portToNeighbor) == null) {
+            portDeviceMap.put(portToNeighbor, neighborId);
+        }
+    }
+
+    protected Set<Set<DeviceId>> getPowerSetOfNeighbors(Set<DeviceId> neighbors) {
+        List<DeviceId> list = new ArrayList<DeviceId>(neighbors);
+        Set<Set<DeviceId>> sets = new HashSet<Set<DeviceId>>();
+        // get the number of elements in the neighbors
+        int elements = list.size();
+        // the number of members of a power set is 2^n
+        // including the empty set
+        int powerElements = (1 << elements);
+
+        // run a binary counter for the number of power elements
+        // NOTE: Exclude empty set
+        for (long i = 1; i < powerElements; i++) {
+            Set<DeviceId> neighborSubSet = new HashSet<DeviceId>();
+            for (int j = 0; j < elements; j++) {
+                if ((i >> j) % 2 == 1) {
+                    neighborSubSet.add(list.get(j));
+                }
+            }
+            sets.add(neighborSubSet);
+        }
+        return sets;
+    }
+
+    private boolean isSegmentIdSameAsNodeSegmentId(DeviceId deviceId, int sId) {
+        return (deviceConfig.getSegmentId(deviceId) == sId);
+    }
+
+    protected List<Integer> getSegmentIdsTobePairedWithNeighborSet(Set<DeviceId> neighbors) {
+
+        List<Integer> nsSegmentIds = new ArrayList<Integer>();
+
+        // Always pair up with no edge label
+        // If (neighbors.size() == 1) {
+        nsSegmentIds.add(-1);
+        // }
+
+        // Filter out SegmentIds matching with the
+        // nodes in the combo
+        for (Integer sId : allSegmentIds) {
+            if (sId.equals(nodeSegmentId)) {
+                continue;
+            }
+            boolean filterOut = false;
+            // Check if the edge label being set is of
+            // any node in the Neighbor set
+            for (DeviceId deviceId : neighbors) {
+                if (isSegmentIdSameAsNodeSegmentId(deviceId, sId)) {
+                    filterOut = true;
+                    break;
+                }
+            }
+            if (!filterOut) {
+                nsSegmentIds.add(sId);
+            }
+        }
+        return nsSegmentIds;
+    }
+
+    /**
+     * Creates Groups from a set of NeighborSet given.
+     *
+     * @param nsSet a set of NeighborSet
+     */
+    public void createGroupsFromNeighborsets(Set<NeighborSet> nsSet) {
+        for (NeighborSet ns : nsSet) {
+            int nextId = flowObjectiveService.allocateNextId();
+            NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                    .builder().withId(nextId)
+                    .withType(NextObjective.Type.HASHED).fromApp(appId);
+            for (DeviceId d : ns.getDeviceIds()) {
+                if (devicePortMap.get(d) == null) {
+                    log.warn("Device {} is not in the port map yet", d);
+                    return;
+                } else if (devicePortMap.get(d).size() == 0) {
+                    log.warn("There are no ports for "
+                            + "the Device {} in the port map yet", d);
+                    return;
+                }
+
+                for (PortNumber sp : devicePortMap.get(d)) {
+                    TrafficTreatment.Builder tBuilder = DefaultTrafficTreatment
+                            .builder();
+                    tBuilder.setOutput(sp)
+                            .setEthDst(deviceConfig.getDeviceMac(d))
+                            .setEthSrc(nodeMacAddr);
+                    if (ns.getEdgeLabel() != NeighborSet.NO_EDGE_LABEL) {
+                        tBuilder.pushMpls().setMpls(MplsLabel.mplsLabel(ns
+                                .getEdgeLabel()));
+                    }
+                    nextObjBuilder.addTreatment(tBuilder.build());
+                }
+            }
+
+            NextObjective nextObj = nextObjBuilder.
+                    add(new SRNextObjectiveContext(deviceId));
+            flowObjectiveService.next(deviceId, nextObj);
+            log.debug("createGroupsFromNeighborsets: Submited "
+                            + "next objective {} in device {}",
+                    nextId, deviceId);
+            nsNextObjStore.put(new NeighborSetNextObjectiveStoreKey(deviceId, ns),
+                               nextId);
+        }
+    }
+
+    public GroupKey getGroupKey(Object obj) {
+        return new DefaultGroupKey(kryo.build().serialize(obj));
+    }
+
+    /**
+     * Removes groups for the next objective ID given.
+     *
+     * @param objectiveId next objective ID to remove
+     * @return true if succeeds, false otherwise
+     */
+    public boolean removeGroup(int objectiveId) {
+
+        if (nsNextObjStore.containsValue(objectiveId)) {
+            NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                    .builder().withId(objectiveId)
+                    .withType(NextObjective.Type.HASHED).fromApp(appId);
+            NextObjective nextObjective = nextObjBuilder.
+                    remove(new SRNextObjectiveContext(deviceId));
+            flowObjectiveService.next(deviceId, nextObjective);
+
+            for (Map.Entry<NeighborSetNextObjectiveStoreKey, Integer> entry: nsNextObjStore.entrySet()) {
+                if (entry.getValue().equals(objectiveId)) {
+                    nsNextObjStore.remove(entry.getKey());
+                    break;
+                }
+            }
+            return true;
+        }
+
+        return false;
+    }
+
+    protected static class SRNextObjectiveContext implements ObjectiveContext {
+        final DeviceId deviceId;
+
+        SRNextObjectiveContext(DeviceId deviceId) {
+            this.deviceId = deviceId;
+        }
+        @Override
+        public void onSuccess(Objective objective) {
+            log.debug("Next objective operation successful in device {}",
+                      deviceId);
+        }
+
+        @Override
+        public void onError(Objective objective, ObjectiveError error) {
+            log.warn("Next objective {} operation failed with error: {} in device {}",
+                     objective, error, deviceId);
+        }
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultTransitGroupHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultTransitGroupHandler.java
new file mode 100644
index 00000000..e12426c2
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DefaultTransitGroupHandler.java
@@ -0,0 +1,185 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.link.LinkService;
+import org.onosproject.store.service.EventuallyConsistentMap;
+
+/**
+ * Default ECMP group handler creation module for a transit device.
+ * This component creates a set of ECMP groups for every neighbor
+ * that this device is connected to.
+ * For example, consider a network of 4 devices: D0 (Segment ID: 100),
+ * D1 (Segment ID: 101), D2 (Segment ID: 102) and D3 (Segment ID: 103),
+ * where D0 and D3 are edge devices and D1 and D2 are transit devices.
+ * Assume transit device D1 is connected to 2 neighbors (D0 and D3 ).
+ * The following groups will be created in D1:
+ * 1) all ports to D0 + with no label push,
+ * 2) all ports to D3 + with no label push,
+ */
+public class DefaultTransitGroupHandler extends DefaultGroupHandler {
+
+    protected DefaultTransitGroupHandler(DeviceId deviceId,
+                                  ApplicationId appId,
+                                  DeviceProperties config,
+                                  LinkService linkService,
+                                  FlowObjectiveService flowObjService,
+                                  EventuallyConsistentMap<
+                                  NeighborSetNextObjectiveStoreKey,
+                                  Integer> nsNextObjStore) {
+        super(deviceId, appId, config, linkService, flowObjService, nsNextObjStore);
+    }
+
+    @Override
+    public void createGroups() {
+        Set<DeviceId> neighbors = devicePortMap.keySet();
+        if (neighbors == null || neighbors.isEmpty()) {
+            return;
+        }
+
+        // Create all possible Neighbor sets from this router
+        // NOTE: Avoid any pairings of edge routers only
+        Set<Set<DeviceId>> sets = getPowerSetOfNeighbors(neighbors);
+        sets = filterEdgeRouterOnlyPairings(sets);
+        log.debug("createGroupsAtTransitRouter: The size of neighbor powerset "
+                + "for sw {} is {}", deviceId, sets.size());
+        Set<NeighborSet> nsSet = new HashSet<NeighborSet>();
+        for (Set<DeviceId> combo : sets) {
+            if (combo.isEmpty()) {
+                continue;
+            }
+            NeighborSet ns = new NeighborSet(combo);
+            log.debug("createGroupsAtTransitRouter: sw {} combo {} ns {}",
+                      deviceId, combo, ns);
+            nsSet.add(ns);
+        }
+        log.debug("createGroupsAtTransitRouter: The neighborset with label "
+                + "for sw {} is {}", deviceId, nsSet);
+
+        createGroupsFromNeighborsets(nsSet);
+    }
+
+    @Override
+    protected void newNeighbor(Link newNeighborLink) {
+        log.debug("New Neighbor: Updating groups for "
+                + "transit device {}", deviceId);
+        // Recompute neighbor power set
+        addNeighborAtPort(newNeighborLink.dst().deviceId(),
+                          newNeighborLink.src().port());
+        // Compute new neighbor sets due to the addition of new neighbor
+        Set<NeighborSet> nsSet = computeImpactedNeighborsetForPortEvent(
+                                             newNeighborLink.dst().deviceId(),
+                                             devicePortMap.keySet());
+        createGroupsFromNeighborsets(nsSet);
+    }
+
+    @Override
+    protected void newPortToExistingNeighbor(Link newNeighborLink) {
+        /*log.debug("New port to existing neighbor: Updating "
+                + "groups for transit device {}", deviceId);
+        addNeighborAtPort(newNeighborLink.dst().deviceId(),
+                          newNeighborLink.src().port());
+        Set<NeighborSet> nsSet = computeImpactedNeighborsetForPortEvent(
+                                              newNeighborLink.dst().deviceId(),
+                                              devicePortMap.keySet());
+        for (NeighborSet ns : nsSet) {
+            // Create the new bucket to be updated
+            TrafficTreatment.Builder tBuilder =
+                    DefaultTrafficTreatment.builder();
+            tBuilder.setOutput(newNeighborLink.src().port())
+                    .setEthDst(deviceConfig.getDeviceMac(
+                          newNeighborLink.dst().deviceId()))
+                    .setEthSrc(nodeMacAddr);
+            if (ns.getEdgeLabel() != NeighborSet.NO_EDGE_LABEL) {
+                tBuilder.pushMpls()
+                        .setMpls(MplsLabel.
+                                 mplsLabel(ns.getEdgeLabel()));
+            }
+
+
+            Integer nextId = deviceNextObjectiveIds.get(ns);
+            if (nextId != null) {
+                NextObjective.Builder nextObjBuilder = DefaultNextObjective
+                        .builder().withId(nextId)
+                        .withType(NextObjective.Type.HASHED).fromApp(appId);
+
+                nextObjBuilder.addTreatment(tBuilder.build());
+
+                NextObjective nextObjective = nextObjBuilder.add();
+                flowObjectiveService.next(deviceId, nextObjective);
+            }
+        }*/
+    }
+
+    @Override
+    protected Set<NeighborSet> computeImpactedNeighborsetForPortEvent(
+                                            DeviceId impactedNeighbor,
+                                            Set<DeviceId> updatedNeighbors) {
+        Set<Set<DeviceId>> powerSet = getPowerSetOfNeighbors(updatedNeighbors);
+
+        Set<DeviceId> tmp = new HashSet<DeviceId>();
+        tmp.addAll(updatedNeighbors);
+        tmp.remove(impactedNeighbor);
+        Set<Set<DeviceId>> tmpPowerSet = getPowerSetOfNeighbors(tmp);
+
+        // Compute the impacted neighbor sets
+        powerSet.removeAll(tmpPowerSet);
+
+        powerSet = filterEdgeRouterOnlyPairings(powerSet);
+        Set<NeighborSet> nsSet = new HashSet<NeighborSet>();
+        for (Set<DeviceId> combo : powerSet) {
+            if (combo.isEmpty()) {
+                continue;
+            }
+            NeighborSet ns = new NeighborSet(combo);
+            log.debug("createGroupsAtTransitRouter: sw {} combo {} ns {}",
+                      deviceId, combo, ns);
+            nsSet.add(ns);
+        }
+        log.debug("computeImpactedNeighborsetForPortEvent: The neighborset with label "
+                + "for sw {} is {}", deviceId, nsSet);
+
+        return nsSet;
+    }
+
+    private Set<Set<DeviceId>> filterEdgeRouterOnlyPairings(Set<Set<DeviceId>> sets) {
+        Set<Set<DeviceId>> fiteredSets = new HashSet<Set<DeviceId>>();
+        for (Set<DeviceId> deviceSubSet : sets) {
+            if (deviceSubSet.size() > 1) {
+                boolean avoidEdgeRouterPairing = true;
+                for (DeviceId device : deviceSubSet) {
+                    if (!deviceConfig.isEdgeDevice(device)) {
+                        avoidEdgeRouterPairing = false;
+                        break;
+                    }
+                }
+                if (!avoidEdgeRouterPairing) {
+                    fiteredSets.add(deviceSubSet);
+                }
+            } else {
+                fiteredSets.add(deviceSubSet);
+            }
+        }
+        return fiteredSets;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DeviceProperties.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DeviceProperties.java
new file mode 100644
index 00000000..816ca7bc
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/DeviceProperties.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import java.util.List;
+
+import org.onlab.packet.MacAddress;
+import org.onosproject.net.DeviceId;
+
+/**
+ * Mechanism through which group handler module retrieves
+ * the device specific attributes such as segment ID,
+ * Mac address...etc from group handler applications.
+ */
+public interface DeviceProperties {
+    /**
+     * Returns the segment id of a device to be used in group creation.
+     *
+     * @param deviceId device identifier
+     * @return segment id of a device
+     */
+    int getSegmentId(DeviceId deviceId);
+    /**
+     * Returns the Mac address of a device to be used in group creation.
+     *
+     * @param deviceId device identifier
+     * @return mac address of a device
+     */
+    MacAddress getDeviceMac(DeviceId deviceId);
+    /**
+     * Indicates whether a device is edge device or transit/core device.
+     *
+     * @param deviceId device identifier
+     * @return boolean
+     */
+    boolean isEdgeDevice(DeviceId deviceId);
+    /**
+     * Returns all segment IDs to be considered in building auto
+     *
+     * created groups.
+     * @return list of segment IDs
+     */
+    List<Integer> getAllDeviceSegmentIds();
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/GroupBucketIdentifier.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/GroupBucketIdentifier.java
new file mode 100644
index 00000000..2ecb4493
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/GroupBucketIdentifier.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import org.onosproject.net.PortNumber;
+
+/**
+ * Representation of policy group bucket identifier. Not exposed to
+ * the application and only to be used internally.
+ */
+public class GroupBucketIdentifier {
+    private int label;
+    private BucketOutputType type;
+    private PortNumber outPort;
+    private PolicyGroupIdentifier outGroup;
+
+    protected enum BucketOutputType {
+        PORT,
+        GROUP
+    }
+
+    protected GroupBucketIdentifier(int label,
+                                    PortNumber outPort) {
+        this.label = label;
+        this.type = BucketOutputType.PORT;
+        this.outPort = checkNotNull(outPort);
+        this.outGroup = null;
+    }
+
+    protected GroupBucketIdentifier(int label,
+                                    PolicyGroupIdentifier outGroup) {
+        this.label = label;
+        this.type = BucketOutputType.GROUP;
+        this.outPort = null;
+        this.outGroup = checkNotNull(outGroup);
+    }
+
+    protected int label() {
+        return this.label;
+    }
+
+    protected BucketOutputType type() {
+        return this.type;
+    }
+
+    protected PortNumber outPort() {
+        return this.outPort;
+    }
+
+    protected PolicyGroupIdentifier outGroup() {
+        return this.outGroup;
+    }
+}
+
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSet.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSet.java
new file mode 100644
index 00000000..7ada3224
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSet.java
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting.grouphandler;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+
+import org.onosproject.net.DeviceId;
+
+/**
+ * Representation of a set of neighbor switch dpids along with edge node
+ * label. Meant to be used as a lookup-key in a hash-map to retrieve an
+ * ECMP-group that hashes packets to a set of ports connecting to the
+ * neighbors in this set.
+ */
+public class NeighborSet {
+    private final Set<DeviceId> neighbors;
+    private final int edgeLabel;
+    public static final int NO_EDGE_LABEL = -1;
+
+    /**
+     * Constructor with set of neighbors. Edge label is
+     * default to -1.
+     *
+     * @param neighbors set of neighbors to be part of neighbor set
+     */
+    public NeighborSet(Set<DeviceId> neighbors) {
+        checkNotNull(neighbors);
+        this.edgeLabel = NO_EDGE_LABEL;
+        this.neighbors = new HashSet<DeviceId>();
+        this.neighbors.addAll(neighbors);
+    }
+
+    /**
+     * Constructor with set of neighbors and edge label.
+     *
+     * @param neighbors set of neighbors to be part of neighbor set
+     * @param edgeLabel label to be pushed as part of group operation
+     */
+    public NeighborSet(Set<DeviceId> neighbors, int edgeLabel) {
+        checkNotNull(neighbors);
+        this.edgeLabel = edgeLabel;
+        this.neighbors = new HashSet<DeviceId>();
+        this.neighbors.addAll(neighbors);
+    }
+
+    /**
+     * Default constructor for kryo serialization.
+     */
+    public NeighborSet() {
+        this.edgeLabel = NO_EDGE_LABEL;
+        this.neighbors = new HashSet<DeviceId>();
+    }
+
+    /**
+     * Gets the neighbors part of neighbor set.
+     *
+     * @return set of neighbor identifiers
+     */
+    public Set<DeviceId> getDeviceIds() {
+        return neighbors;
+    }
+
+    /**
+     * Gets the label associated with neighbor set.
+     *
+     * @return integer
+     */
+    public int getEdgeLabel() {
+        return edgeLabel;
+    }
+
+    // The list of neighbor ids and label are used for comparison.
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof NeighborSet)) {
+            return false;
+        }
+        NeighborSet that = (NeighborSet) o;
+        return (this.neighbors.containsAll(that.neighbors) &&
+                that.neighbors.containsAll(this.neighbors) &&
+                (this.edgeLabel == that.edgeLabel));
+    }
+
+    // The list of neighbor ids and label are used for comparison.
+    @Override
+    public int hashCode() {
+        int result = 17;
+        int combinedHash = 0;
+        for (DeviceId d : neighbors) {
+            combinedHash = combinedHash + Objects.hash(d);
+        }
+        result = 31 * result + combinedHash + Objects.hash(edgeLabel);
+
+        return result;
+    }
+
+    @Override
+    public String toString() {
+        return " Neighborset Sw: " + neighbors
+                + " and Label: " + edgeLabel;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSetNextObjectiveStoreKey.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSetNextObjectiveStoreKey.java
new file mode 100644
index 00000000..9ace5313
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/NeighborSetNextObjectiveStoreKey.java
@@ -0,0 +1,72 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting.grouphandler;
+
+import java.util.Objects;
+
+import org.onosproject.net.DeviceId;
+
+/**
+ * Class definition of Key for Neighborset to NextObjective store.
+ */
+public class NeighborSetNextObjectiveStoreKey {
+    private final DeviceId deviceId;
+    private final NeighborSet ns;
+
+    public NeighborSetNextObjectiveStoreKey(DeviceId deviceId,
+                                            NeighborSet ns) {
+        this.deviceId = deviceId;
+        this.ns = ns;
+    }
+
+    public DeviceId deviceId() {
+        return this.deviceId;
+    }
+
+    public NeighborSet neighborSet() {
+        return this.ns;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof NeighborSetNextObjectiveStoreKey)) {
+            return false;
+        }
+        NeighborSetNextObjectiveStoreKey that =
+                (NeighborSetNextObjectiveStoreKey) o;
+        return (Objects.equals(this.deviceId, that.deviceId) &&
+                Objects.equals(this.ns, that.ns));
+    }
+
+    // The list of neighbor ids and label are used for comparison.
+    @Override
+    public int hashCode() {
+        int result = 17;
+        result = 31 * result + Objects.hashCode(this.deviceId)
+                + Objects.hashCode(this.ns);
+
+        return result;
+    }
+
+    @Override
+    public String toString() {
+        return "Device: " + deviceId + " Neighborset: " + ns;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupHandler.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupHandler.java
new file mode 100644
index 00000000..e7e87839
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupHandler.java
@@ -0,0 +1,352 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static org.slf4j.LoggerFactory.getLogger;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+
+import org.onlab.packet.MplsLabel;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.segmentrouting.grouphandler.GroupBucketIdentifier.BucketOutputType;
+import org.onosproject.store.service.EventuallyConsistentMap;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flowobjective.FlowObjectiveService;
+import org.onosproject.net.group.GroupBucket;
+import org.onosproject.net.link.LinkService;
+import org.slf4j.Logger;
+
+/**
+ * A module to create group chains based on the specified device
+ * ports and label stack to be applied on each port.
+ */
+public class PolicyGroupHandler extends DefaultGroupHandler {
+
+    private final Logger log = getLogger(getClass());
+    private HashMap<PolicyGroupIdentifier, PolicyGroupIdentifier> dependentGroups = new HashMap<>();
+
+    /**
+     * Policy group handler constructor.
+     *
+     * @param deviceId device identifier
+     * @param appId application identifier
+     * @param config interface to retrieve the device properties
+     * @param linkService link service object
+     * @param flowObjService flow objective service object
+     * @param nsNextObjStore next objective store map
+     */
+    public PolicyGroupHandler(DeviceId deviceId,
+                              ApplicationId appId,
+                              DeviceProperties config,
+                              LinkService linkService,
+                              FlowObjectiveService flowObjService,
+                              EventuallyConsistentMap<NeighborSetNextObjectiveStoreKey,
+                                      Integer> nsNextObjStore) {
+        super(deviceId, appId, config, linkService, flowObjService, nsNextObjStore);
+    }
+
+    public PolicyGroupIdentifier createPolicyGroupChain(String id,
+                                                        List<PolicyGroupParams> params) {
+        List<GroupBucketIdentifier> bucketIds = new ArrayList<>();
+        for (PolicyGroupParams param: params) {
+            List<PortNumber> ports = param.getPorts();
+            if (ports == null) {
+                log.warn("createPolicyGroupChain in sw {} with wrong "
+                        + "input parameters", deviceId);
+                return null;
+            }
+
+            int labelStackSize = (param.getLabelStack() != null) ?
+                                      param.getLabelStack().size() : 0;
+
+            if (labelStackSize > 1) {
+                for (PortNumber sp : ports) {
+                    PolicyGroupIdentifier previousGroupkey = null;
+                    DeviceId neighbor = portDeviceMap.get(sp);
+                    for (int idx = 0; idx < param.getLabelStack().size(); idx++) {
+                        int label = param.getLabelStack().get(idx);
+                        if (idx == (labelStackSize - 1)) {
+                            // Innermost Group
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label,
+                                                              previousGroupkey);
+                            bucketIds.add(bucketId);
+                        } else if (idx == 0) {
+                            // Outermost Group
+                            List<GroupBucket> outBuckets = new ArrayList<>();
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label, sp);
+                            PolicyGroupIdentifier key = new
+                                    PolicyGroupIdentifier(id,
+                                                          Collections.singletonList(param),
+                                                          Collections.singletonList(bucketId));
+                            TrafficTreatment.Builder tBuilder =
+                                    DefaultTrafficTreatment.builder();
+                            tBuilder.setOutput(sp)
+                                    .setEthDst(deviceConfig.
+                                               getDeviceMac(neighbor))
+                                    .setEthSrc(nodeMacAddr)
+                                    .pushMpls()
+                                    .setMpls(MplsLabel.mplsLabel(label));
+                            /*outBuckets.add(DefaultGroupBucket.
+                                           createSelectGroupBucket(tBuilder.build()));
+                            GroupDescription desc = new
+                                    DefaultGroupDescription(deviceId,
+                                                            GroupDescription.Type.INDIRECT,
+                                                            new GroupBuckets(outBuckets));
+                            //TODO: BoS*/
+                            previousGroupkey = key;
+                            //groupService.addGroup(desc);
+                            //TODO: Use nextObjective APIs here
+                        } else {
+                            // Intermediate Groups
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label,
+                                                              previousGroupkey);
+                            PolicyGroupIdentifier key = new
+                                    PolicyGroupIdentifier(id,
+                                                          Collections.singletonList(param),
+                                                          Collections.singletonList(bucketId));
+                            // Add to group dependency list
+                            dependentGroups.put(previousGroupkey, key);
+                            previousGroupkey = key;
+                        }
+                    }
+                }
+            } else {
+                int label = -1;
+                if (labelStackSize == 1) {
+                    label = param.getLabelStack().get(0);
+                }
+                for (PortNumber sp : ports) {
+                    GroupBucketIdentifier bucketId =
+                            new GroupBucketIdentifier(label, sp);
+                    bucketIds.add(bucketId);
+                }
+            }
+        }
+        PolicyGroupIdentifier innermostGroupkey = null;
+        if (!bucketIds.isEmpty()) {
+            innermostGroupkey = new
+                    PolicyGroupIdentifier(id,
+                                          params,
+                                          bucketIds);
+            // Add to group dependency list
+            boolean fullyResolved = true;
+            for (GroupBucketIdentifier bucketId:bucketIds) {
+                if (bucketId.type() == BucketOutputType.GROUP) {
+                    dependentGroups.put(bucketId.outGroup(),
+                                        innermostGroupkey);
+                    fullyResolved = false;
+                }
+            }
+
+            if (fullyResolved) {
+                List<GroupBucket> outBuckets = new ArrayList<>();
+                for (GroupBucketIdentifier bucketId:bucketIds) {
+                    DeviceId neighbor = portDeviceMap.
+                            get(bucketId.outPort());
+                    TrafficTreatment.Builder tBuilder =
+                            DefaultTrafficTreatment.builder();
+                    tBuilder.setOutput(bucketId.outPort())
+                            .setEthDst(deviceConfig.
+                                       getDeviceMac(neighbor))
+                            .setEthSrc(nodeMacAddr);
+                    if (bucketId.label() != NeighborSet.NO_EDGE_LABEL) {
+                        tBuilder.pushMpls()
+                            .setMpls(MplsLabel.mplsLabel(bucketId.label()));
+                    }
+                    //TODO: BoS
+                    /*outBuckets.add(DefaultGroupBucket.
+                                   createSelectGroupBucket(tBuilder.build()));*/
+                }
+                /*GroupDescription desc = new
+                        DefaultGroupDescription(deviceId,
+                                                GroupDescription.Type.SELECT,
+                                                new GroupBuckets(outBuckets));
+                groupService.addGroup(desc);*/
+                //TODO: Use nextObjective APIs here
+            }
+        }
+        return innermostGroupkey;
+    }
+
+    //TODO: Use nextObjective APIs to handle the group chains
+    /*@Override
+    protected void handleGroupEvent(GroupEvent event) {
+        if (event.type() == GroupEvent.Type.GROUP_ADDED) {
+            if (dependentGroups.get(event.subject().appCookie()) != null) {
+                PolicyGroupIdentifier dependentGroupKey = dependentGroups.get(event.subject().appCookie());
+                dependentGroups.remove(event.subject().appCookie());
+                boolean fullyResolved = true;
+                for (GroupBucketIdentifier bucketId:
+                            dependentGroupKey.bucketIds()) {
+                    if (bucketId.type() != BucketOutputType.GROUP) {
+                        continue;
+                    }
+                    if (dependentGroups.containsKey(bucketId.outGroup())) {
+                        fullyResolved = false;
+                        break;
+                    }
+                }
+
+                if (fullyResolved) {
+                    List<GroupBucket> outBuckets = new ArrayList<GroupBucket>();
+                    for (GroupBucketIdentifier bucketId:
+                                dependentGroupKey.bucketIds()) {
+                        TrafficTreatment.Builder tBuilder =
+                                DefaultTrafficTreatment.builder();
+                        if (bucketId.label() != NeighborSet.NO_EDGE_LABEL) {
+                            tBuilder.pushMpls()
+                                    .setMpls(MplsLabel.
+                                             mplsLabel(bucketId.label()));
+                        }
+                        //TODO: BoS
+                        if (bucketId.type() == BucketOutputType.PORT) {
+                            DeviceId neighbor = portDeviceMap.
+                                        get(bucketId.outPort());
+                            tBuilder.setOutput(bucketId.outPort())
+                                    .setEthDst(deviceConfig.
+                                               getDeviceMac(neighbor))
+                                     .setEthSrc(nodeMacAddr);
+                        } else {
+                            if (groupService.
+                                    getGroup(deviceId,
+                                             getGroupKey(bucketId.
+                                                       outGroup())) == null) {
+                                throw new IllegalStateException();
+                            }
+                            GroupId indirectGroupId = groupService.
+                                    getGroup(deviceId,
+                                             getGroupKey(bucketId.
+                                                         outGroup())).id();
+                            tBuilder.group(indirectGroupId);
+                        }
+                        outBuckets.add(DefaultGroupBucket.
+                                       createSelectGroupBucket(tBuilder.build()));
+                    }
+                    GroupDescription desc = new
+                            DefaultGroupDescription(deviceId,
+                                                    GroupDescription.Type.SELECT,
+                                                    new GroupBuckets(outBuckets));
+                    groupService.addGroup(desc);
+                }
+            }
+        }
+    }*/
+
+    public PolicyGroupIdentifier generatePolicyGroupKey(String id,
+                                   List<PolicyGroupParams> params) {
+        List<GroupBucketIdentifier> bucketIds = new ArrayList<>();
+        for (PolicyGroupParams param: params) {
+            List<PortNumber> ports = param.getPorts();
+            if (ports == null) {
+                log.warn("generateGroupKey in sw {} with wrong "
+                        + "input parameters", deviceId);
+                return null;
+            }
+
+            int labelStackSize = (param.getLabelStack() != null)
+                    ? param.getLabelStack().size() : 0;
+
+            if (labelStackSize > 1) {
+                for (PortNumber sp : ports) {
+                    PolicyGroupIdentifier previousGroupkey = null;
+                    for (int idx = 0; idx < param.getLabelStack().size(); idx++) {
+                        int label = param.getLabelStack().get(idx);
+                        if (idx == (labelStackSize - 1)) {
+                            // Innermost Group
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label,
+                                                              previousGroupkey);
+                            bucketIds.add(bucketId);
+                        } else if (idx == 0) {
+                            // Outermost Group
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label, sp);
+                            PolicyGroupIdentifier key = new
+                                    PolicyGroupIdentifier(id,
+                                                          Collections.singletonList(param),
+                                                          Collections.singletonList(bucketId));
+                            previousGroupkey = key;
+                        } else {
+                            // Intermediate Groups
+                            GroupBucketIdentifier bucketId =
+                                    new GroupBucketIdentifier(label,
+                                                              previousGroupkey);
+                            PolicyGroupIdentifier key = new
+                                    PolicyGroupIdentifier(id,
+                                                          Collections.singletonList(param),
+                                                          Collections.singletonList(bucketId));
+                            previousGroupkey = key;
+                        }
+                    }
+                }
+            } else {
+                int label = -1;
+                if (labelStackSize == 1) {
+                    label = param.getLabelStack().get(0);
+                }
+                for (PortNumber sp : ports) {
+                    GroupBucketIdentifier bucketId =
+                            new GroupBucketIdentifier(label, sp);
+                    bucketIds.add(bucketId);
+                }
+            }
+        }
+        PolicyGroupIdentifier innermostGroupkey = null;
+        if (!bucketIds.isEmpty()) {
+            innermostGroupkey = new
+                    PolicyGroupIdentifier(id,
+                                          params,
+                                          bucketIds);
+        }
+        return innermostGroupkey;
+    }
+
+    public void removeGroupChain(PolicyGroupIdentifier key) {
+        checkArgument(key != null);
+        List<PolicyGroupIdentifier> groupsToBeDeleted = new ArrayList<>();
+        groupsToBeDeleted.add(key);
+
+        Iterator<PolicyGroupIdentifier> it =
+                groupsToBeDeleted.iterator();
+
+        while (it.hasNext()) {
+            PolicyGroupIdentifier innerMostGroupKey = it.next();
+            for (GroupBucketIdentifier bucketId:
+                        innerMostGroupKey.bucketIds()) {
+                if (bucketId.type() != BucketOutputType.GROUP) {
+                    groupsToBeDeleted.add(bucketId.outGroup());
+                }
+            }
+            /*groupService.removeGroup(deviceId,
+                                     getGroupKey(innerMostGroupKey),
+                                     appId);*/
+            //TODO: Use nextObjective APIs here
+            it.remove();
+        }
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java
new file mode 100644
index 00000000..44a0a2ce
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupIdentifier.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import java.util.List;
+
+/**
+ * Representation of policy based group identifiers.
+ * Opaque to group handler applications and only the outermost
+ * policy group identifier in a chain is visible to the applications.
+ */
+public class PolicyGroupIdentifier {
+    private String id;
+    private List<PolicyGroupParams> inputParams;
+    private List<GroupBucketIdentifier> bucketIds;
+
+    /**
+     * Constructor.
+     *
+     * @param id unique identifier associated with the policy group
+     * @param input policy group params associated with this group
+     * @param bucketIds buckets associated with this group
+     */
+    protected PolicyGroupIdentifier(String id,
+                                 List<PolicyGroupParams> input,
+                                 List<GroupBucketIdentifier> bucketIds) {
+        this.id = id;
+        this.inputParams = input;
+        this.bucketIds = bucketIds;
+    }
+
+    /**
+     * Returns the bucket identifier list associated with the policy
+     * group identifier.
+     *
+     * @return list of bucket identifier
+     */
+    protected List<GroupBucketIdentifier> bucketIds() {
+        return this.bucketIds;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = 17;
+        int combinedHash = 0;
+        for (PolicyGroupParams input:inputParams) {
+            combinedHash = combinedHash + input.hashCode();
+        }
+        for (GroupBucketIdentifier bucketId:bucketIds) {
+            combinedHash = combinedHash + bucketId.hashCode();
+        }
+        result = 31 * result + combinedHash;
+
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof PolicyGroupIdentifier) {
+            PolicyGroupIdentifier that = (PolicyGroupIdentifier) obj;
+            boolean result = this.id.equals(that.id);
+            result = result &&
+                    this.inputParams.containsAll(that.inputParams) &&
+                    that.inputParams.containsAll(this.inputParams);
+            result = result &&
+                    this.bucketIds.containsAll(that.bucketIds) &&
+                    that.bucketIds.containsAll(this.bucketIds);
+            return result;
+        }
+
+        return false;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupParams.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupParams.java
new file mode 100644
index 00000000..5a3f26b5
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/PolicyGroupParams.java
@@ -0,0 +1,92 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.grouphandler;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.util.List;
+import java.util.Objects;
+
+import org.onosproject.net.PortNumber;
+
+/**
+ * Representation of parameters used to create policy based groups.
+ */
+public class PolicyGroupParams {
+    private final List<PortNumber> ports;
+    private final List<Integer> labelStack;
+
+    /**
+     * Constructor.
+     *
+     * @param labelStack mpls label stack to be applied on the ports
+     * @param ports ports to be part of the policy group
+     */
+    public PolicyGroupParams(List<Integer> labelStack,
+                             List<PortNumber> ports) {
+        this.ports = checkNotNull(ports);
+        this.labelStack = checkNotNull(labelStack);
+    }
+
+    /**
+     * Returns the ports associated with the policy group params.
+     *
+     * @return list of port numbers
+     */
+    public List<PortNumber> getPorts() {
+        return ports;
+    }
+
+    /**
+     * Returns the label stack associated with the policy group params.
+     *
+     * @return list of integers
+     */
+    public List<Integer> getLabelStack() {
+        return labelStack;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = 17;
+        int combinedHash = 0;
+        for (PortNumber port:ports) {
+            combinedHash = combinedHash + port.hashCode();
+        }
+        combinedHash = combinedHash + Objects.hash(labelStack);
+        result = 31 * result + combinedHash;
+
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof PolicyGroupParams) {
+            PolicyGroupParams that = (PolicyGroupParams) obj;
+            boolean result = this.labelStack.equals(that.labelStack);
+            result = result &&
+                    this.ports.containsAll(that.ports) &&
+                    that.ports.containsAll(this.ports);
+            return result;
+        }
+
+        return false;
+    }
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/package-info.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/package-info.java
new file mode 100644
index 00000000..1a8d595e
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/grouphandler/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Segment routing group handling.
+ */
+package org.onosproject.segmentrouting.grouphandler;
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/package-info.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/package-info.java
new file mode 100644
index 00000000..7b81db8a
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Segment routing application components.
+ */
+package org.onosproject.segmentrouting;
\ No newline at end of file
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyCodec.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyCodec.java
new file mode 100644
index 00000000..8e508872
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyCodec.java
@@ -0,0 +1,122 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.web;
+
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.segmentrouting.Policy;
+import org.onosproject.segmentrouting.TunnelPolicy;
+
+public final class PolicyCodec extends JsonCodec<Policy> {
+
+    // JSON field names
+    private static final String POLICY_ID = "policy_id";
+    private static final String PRIORITY = "priority";
+    private static final String TYPE = "policy_type";
+    private static final String TUNNEL_ID = "tunnel_id";
+    private static final String DST_IP = "dst_ip";
+    private static final String SRC_IP = "src_ip";
+    private static final String PROTO_TYPE = "proto_type";
+    private static final String SRC_PORT = "src_tp_port";
+    private static final String DST_PORT = "dst_tp_port";
+
+    @Override
+    public ObjectNode encode(Policy policy, CodecContext context) {
+        final ObjectNode result = context.mapper().createObjectNode()
+                .put(POLICY_ID, policy.id());
+
+        result.put(PRIORITY, policy.priority());
+        result.put(TYPE, policy.type().toString());
+
+        if (policy.dstIp() != null) {
+            result.put(DST_IP, policy.dstIp());
+        }
+        if (policy.srcIp() != null) {
+            result.put(SRC_IP, policy.srcIp());
+        }
+        if (policy.ipProto() != null) {
+            result.put(PROTO_TYPE, policy.ipProto());
+        }
+
+        int srcPort = policy.srcPort() & 0xffff;
+        if (policy.srcPort() != 0) {
+            result.put(SRC_PORT, srcPort);
+        }
+        int dstPort = policy.dstPort() & 0xffff;
+        if (policy.dstPort() != 0) {
+            result.put(DST_PORT, dstPort);
+        }
+        if (policy.type() == Policy.Type.TUNNEL_FLOW) {
+            result.put(TUNNEL_ID, ((TunnelPolicy) policy).tunnelId());
+        }
+
+        return result;
+    }
+
+    @Override
+    public Policy decode(ObjectNode json, CodecContext context) {
+
+        String pid = json.path(POLICY_ID).asText();
+        String type = json.path(TYPE).asText();
+        int priority = json.path(PRIORITY).asInt();
+        String dstIp = json.path(DST_IP).asText();
+        String srcIp = json.path(SRC_IP).asText();
+        String tunnelId = json.path(TUNNEL_ID).asText();
+        String protoType = json.path(PROTO_TYPE).asText();
+        short srcPort = json.path(SRC_PORT).shortValue();
+        short dstPort = json.path(DST_PORT).shortValue();
+
+        if (json.path(POLICY_ID).isMissingNode() || pid == null) {
+            // TODO: handle errors
+            return null;
+        }
+
+        TunnelPolicy.Builder tpb = TunnelPolicy.builder().setPolicyId(pid);
+        if (!json.path(TYPE).isMissingNode() && type != null &&
+                Policy.Type.valueOf(type).equals(Policy.Type.TUNNEL_FLOW)) {
+
+            if (json.path(TUNNEL_ID).isMissingNode() || tunnelId == null) {
+                return null;
+            }
+
+            tpb.setTunnelId(tunnelId);
+            tpb.setType(Policy.Type.valueOf(type));
+
+            if (!json.path(PRIORITY).isMissingNode()) {
+                tpb.setPriority(priority);
+            }
+            if (dstIp != null) {
+                tpb.setDstIp(dstIp);
+            }
+            if (srcIp != null) {
+                tpb.setSrcIp(srcIp);
+            }
+            if (protoType != null) {
+                tpb.setIpProto(protoType);
+            }
+            if (dstPort != 0) {
+                tpb.setDstPort(dstPort);
+            }
+            if (srcPort != 0) {
+                tpb.setSrcPort(srcPort);
+            }
+        }
+
+        return tpb.build();
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java
new file mode 100644
index 00000000..cdc53a02
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/PolicyWebResource.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.web;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+
+import org.onosproject.rest.AbstractWebResource;
+import org.onosproject.segmentrouting.Policy;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+
+import javax.ws.rs.Consumes;
+import javax.ws.rs.DELETE;
+import javax.ws.rs.GET;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+
+/**
+ * Query, create and remove segment routing plicies.
+ */
+@Path("policy")
+public class PolicyWebResource extends AbstractWebResource {
+
+    private static final PolicyCodec POLICY_CODEC = new PolicyCodec();
+
+    /**
+     * Get all segment routing policies.
+     * Returns an array of segment routing policies.
+     *
+     * @return status of OK
+     */
+    @GET
+    @Produces(MediaType.APPLICATION_JSON)
+    public Response getPolicy() {
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        List<Policy> policies = srService.getPolicies();
+        ObjectNode result = new ObjectMapper().createObjectNode();
+        result.set("policy", new PolicyCodec().encode(policies, this));
+
+        return ok(result.toString()).build();
+    }
+
+    /**
+     * Create a new segment routing policy.
+     *
+     * @param input JSON stream for policy to create
+     * @return status of the request - OK if the policy is created,
+     * INTERNAL_SERVER_ERROR if the JSON is invalid or the policy cannot be created
+     * @throws IOException if JSON processing fails
+     */
+    @POST
+    @Consumes(MediaType.APPLICATION_JSON)
+    public Response createPolicy(InputStream input) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode policyJson = (ObjectNode) mapper.readTree(input);
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        Policy policyInfo = POLICY_CODEC.decode(policyJson, this);
+
+        if (policyInfo.type() == Policy.Type.TUNNEL_FLOW) {
+            srService.createPolicy(policyInfo);
+            return Response.ok().build();
+        } else {
+            return Response.serverError().build();
+        }
+    }
+
+    /**
+     * Delete a segment routing policy.
+     *
+     * @param input JSON stream for policy to delete
+     * @return status of the request - OK if the policy is removed,
+     * INTERNAL_SERVER_ERROR otherwise
+     * @throws IOException if JSON is invalid
+     */
+    @DELETE
+    @Consumes(MediaType.APPLICATION_JSON)
+    public Response removePolicy(InputStream input) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode policyJson = (ObjectNode) mapper.readTree(input);
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        Policy policyInfo = POLICY_CODEC.decode(policyJson, this);
+        // TODO: Check the result
+        srService.removePolicy(policyInfo);
+
+        return Response.ok().build();
+
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java
new file mode 100644
index 00000000..2f85afd5
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.web;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.segmentrouting.DefaultTunnel;
+import org.onosproject.segmentrouting.Tunnel;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class TunnelCodec extends JsonCodec<Tunnel> {
+
+    // JSON field names
+    private static final String TUNNEL_ID = "tunnel_id";
+    private static final String GROUP_ID = "group_id";
+    private static final String LABEL_PATH = "label_path";
+
+    @Override
+    public ObjectNode encode(Tunnel tunnel, CodecContext context) {
+        final ObjectNode result = context.mapper().createObjectNode()
+                .put(TUNNEL_ID, tunnel.id());
+
+        result.put(GROUP_ID, tunnel.groupId());
+
+        final ArrayNode jsonLabelIds = result.putArray(LABEL_PATH);
+
+        tunnel.labelIds().forEach(label -> jsonLabelIds.add(label.intValue()));
+
+        return result;
+    }
+
+    @Override
+    public DefaultTunnel decode(ObjectNode json, CodecContext context) {
+
+        String tid = json.path(TUNNEL_ID).asText();
+        List<Integer> labels = new ArrayList<>();
+
+        if (!json.path(LABEL_PATH).isMissingNode()) {
+            ArrayNode labelArray = (ArrayNode) json.path(LABEL_PATH);
+            for (JsonNode o : labelArray) {
+                labels.add(o.asInt());
+            }
+        }
+
+        return new DefaultTunnel(tid, labels);
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelWebResource.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelWebResource.java
new file mode 100644
index 00000000..fb30308a
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelWebResource.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.segmentrouting.web;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+
+import org.onosproject.rest.AbstractWebResource;
+import org.onosproject.segmentrouting.SegmentRoutingService;
+import org.onosproject.segmentrouting.Tunnel;
+
+import javax.ws.rs.Consumes;
+import javax.ws.rs.DELETE;
+import javax.ws.rs.GET;
+import javax.ws.rs.POST;
+import javax.ws.rs.Path;
+import javax.ws.rs.Produces;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+
+/**
+ * Query, create and remove segment routing tunnels.
+ */
+@Path("tunnel")
+public class TunnelWebResource extends AbstractWebResource {
+
+    private static final TunnelCodec TUNNEL_CODEC = new TunnelCodec();
+
+    /**
+     * Get all segment routing tunnels.
+     * Returns an array of segment routing tunnels.
+     *
+     * @return status of OK
+     */
+    @GET
+    @Produces(MediaType.APPLICATION_JSON)
+    public Response getTunnel() {
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        List<Tunnel> tunnels = srService.getTunnels();
+        ObjectNode result = new ObjectMapper().createObjectNode();
+        result.set("tunnel", new TunnelCodec().encode(tunnels, this));
+
+        return ok(result.toString()).build();
+    }
+
+    /**
+     * Create a new segment routing tunnel.
+     *
+     * @param input JSON stream for tunnel to create
+     * @return status of the request - OK if the tunnel is created,
+     * INTERNAL_SERVER_ERROR if the JSON is invalid or the tunnel cannot be created
+     * @throws IOException if the JSON is invalid
+     */
+    @POST
+    @Consumes(MediaType.APPLICATION_JSON)
+    public Response createTunnel(InputStream input) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode tunnelJson = (ObjectNode) mapper.readTree(input);
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        Tunnel tunnelInfo = TUNNEL_CODEC.decode(tunnelJson, this);
+        srService.createTunnel(tunnelInfo);
+
+        return Response.ok().build();
+    }
+
+    /**
+     * Delete a segment routing tunnel.
+     *
+     * @param input JSON stream for tunnel to delete
+     * @return status of the request - OK if the tunnel is removed,
+     * INTERNAL_SERVER_ERROR otherwise
+     * @throws IOException if JSON is invalid
+     */
+    @DELETE
+    @Consumes(MediaType.APPLICATION_JSON)
+    public Response removeTunnel(InputStream input) throws IOException {
+        ObjectMapper mapper = new ObjectMapper();
+        ObjectNode tunnelJson = (ObjectNode) mapper.readTree(input);
+        SegmentRoutingService srService = get(SegmentRoutingService.class);
+        Tunnel tunnelInfo = TUNNEL_CODEC.decode(tunnelJson, this);
+        srService.removeTunnel(tunnelInfo);
+
+        return Response.ok().build();
+    }
+
+}
diff --git a/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/package-info.java b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/package-info.java
new file mode 100644
index 00000000..85c63de5
--- /dev/null
+++ b/framework/src/onos/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Set of resources implementing the segment routing application REST API.
+ */
+package org.onosproject.segmentrouting.web;
\ No newline at end of file