Merge "Add verigraph code base"

27 files changed, 3329 insertions, 0 deletions

diff --git a/verigraph/service/src/mcnet/components/Checker.java b/verigraph/service/src/mcnet/components/Checker.java
new file mode 100644
index 0000000..3c13d28
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/Checker.java
@@ -0,0 +1,363 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Model;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Status;
+
+/**Various checks for specific properties in the network.
+ *
+ */
+public class Checker {
+
+	Context ctx;
+	Network net;
+	NetContext nctx;
+	Solver solver;
+	ArrayList<BoolExpr> constraints;
+	public BoolExpr [] assertions;
+	public Status result;
+	public Model model;
+
+
+   public Checker(Context context,NetContext nctx,Network network){
+        this.ctx = context;
+        this.net = network;
+        this.nctx = nctx;
+        this.solver = ctx.mkSolver();
+        this.constraints = new ArrayList<BoolExpr>();
+   }
+
+   /**Resets the constraints
+    *
+    */
+    public void clearState (){
+        this.solver.reset();
+        this.constraints = new ArrayList<BoolExpr>();
+    }
+
+	/**Checks whether the source provided can reach the destination
+	 *
+	 * @param src
+	 * @param dest
+	 * @return
+	 */
+	public IsolationResult checkIsolationProperty (NetworkObject src, NetworkObject dest){
+		assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    solver.push ();
+	    addConstraints();
+
+	    Expr p0 = ctx.mkConst("check_isolation_p0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+	    Expr p1 = ctx.mkConst("check_isolation_p1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_1 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    IntExpr t_0 = ctx.mkIntConst("check_isolation_t0_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_1 = ctx.mkIntConst("check_isolation_t1_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p0,t_0)
+	    this.solver.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p0, t_0));
+
+	//	        Constraint2		send(srcNode,n_1,p1,t_1)
+	    this.solver.add((BoolExpr)nctx.send.apply(src.getZ3Node(), n_1, p1, t_1));
+
+	//	        Constraint3		nodeHasAddr(srcNode,p1.srcAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(src.getZ3Node(), nctx.pf.get("src").apply(p1)));
+
+	//	        Constraint4		p1.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p1), src.getZ3Node()));
+
+	//	        Constraint5		nodeHasAddr(destNode,p1.destAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(dest.getZ3Node(), nctx.pf.get("dest").apply(p1)));
+
+		//NON sembrano necessari
+		//         this.solver.add(z3.Or(this.ctx.nodeHasAddr(src.getZ3Node(), this.ctx.packet.src(p0)),\
+		//                               this.ctx.nodeHasAddr(n_0, this.ctx.packet.src(p0)),\
+		//                               this.ctx.nodeHasAddr(n_1, this.ctx.packet.src(p0))))
+		//this.solver.add(this.ctx.packet.dest(p1) == this.ctx.packet.dest(p0))
+
+	//	        Constraint6		p1.origin ==  p0.origin
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p1),nctx.pf.get("origin").apply(p0)));
+
+	//	        Constraint7		nodeHasAddr(destNode, p0.destAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(dest.getZ3Node(), nctx.pf.get("dest").apply(p0)));
+
+	    result = this.solver.check();
+	    model = null;
+	    assertions = this.solver.getAssertions();
+	    if (result == Status.SATISFIABLE){
+	    	model = this.solver.getModel();
+	    }
+	    this.solver.pop();
+	    return new IsolationResult(ctx,result, p0, n_0, t_1, t_0, nctx, assertions, model);
+	}
+
+
+
+	public IsolationResult CheckIsolationFlowProperty (NetworkObject src, NetworkObject dest){
+		assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    solver.push ();
+	    addConstraints();
+
+	    Expr p = ctx.mkConst("check_isolation_p_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_1 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_2 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+
+	    IntExpr t_0 = ctx.mkIntConst("check_isolation_t0_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_1 = ctx.mkIntConst("check_isolation_t1_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_2 = ctx.mkIntConst("check_isolation_t2_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p,t_0)
+	    this.solver.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p, t_0));
+
+	//	        Constraint2		send(srcNode,n_1,p1,t_1)
+	    this.solver.add((BoolExpr)nctx.send.apply(src.getZ3Node(), n_1, p, t_1));
+
+	//	        Constraint3		nodeHasAddr(srcNode,p.srcAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(src.getZ3Node(), nctx.pf.get("src").apply(p)));
+
+	//	        Constraint4		p.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p), src.getZ3Node()));
+
+
+	    Expr p_2 = ctx.mkConst("check_isolation_p_flow_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+
+	    //	    Constraint5		there does not exist p_2, n_2, t_2 :
+							//	    		 send(destNode,n_2,p_2,t_2) &&
+							//	    	     p_2.srcAddr == p. destAddr &&
+							//	    	     p_2.srcPort == p.destPort &&
+							//	    	     p_2.destPort == p.srcPort &&
+							//	    	     p_2.destt == p.src &&
+							//	    	     t_2 < t_0
+	    this.solver.add(ctx.mkNot(ctx.mkExists(new Expr[]{p_2,n_2,t_2},
+	    				ctx.mkAnd(
+	    						(BoolExpr)nctx.send.apply(dest.getZ3Node(), n_2, p_2, t_2),
+	    						ctx.mkEq(nctx.pf.get("src").apply(p_2), nctx.pf.get("dest").apply(p)),
+	    						ctx.mkEq(nctx.pf.get("src_port").apply(p_2), nctx.pf.get("dest_port").apply(p)),
+	    						ctx.mkEq(nctx.pf.get("dest_port").apply(p_2), nctx.pf.get("src_port").apply(p)),
+	    						ctx.mkEq(nctx.pf.get("dest").apply(p_2), nctx.pf.get("src").apply(p)),
+	    						ctx.mkLt(t_2,t_0)),1,null,null,null,null)));
+
+
+	    result = this.solver.check();
+	    model = null;
+	    assertions = this.solver.getAssertions();
+	    if (result == Status.SATISFIABLE){
+	    	model = this.solver.getModel();
+	    }
+	    this.solver.pop();
+	    return new IsolationResult(ctx,result, p, n_0, t_1, t_0, nctx, assertions, model);
+	}
+
+
+
+    public IsolationResult CheckNodeTraversalProperty (NetworkObject src, NetworkObject dest, NetworkObject node){
+		assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    solver.push ();
+	    addConstraints();
+
+	    Expr p = ctx.mkConst("check_isolation_p_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_1 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_2 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+
+	    IntExpr t_0 = ctx.mkIntConst("check_isolation_t0_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_1 = ctx.mkIntConst("check_isolation_t1_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_2 = ctx.mkIntConst("check_isolation_t2_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p,t_0)
+	    this.solver.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p, t_0));
+
+	//	        Constraint2		send(srcNode,n_1,p1,t_1)
+	    this.solver.add((BoolExpr)nctx.send.apply(src.getZ3Node(), n_1, p, t_1));
+
+	//	        Constraint3		nodeHasAddr(srcNode,p.srcAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(src.getZ3Node(), nctx.pf.get("src").apply(p)));
+
+	//	        Constraint4		p.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p), src.getZ3Node()));
+
+
+	//			Constraint5		there does not exist n_2, t_2 : recv(n_2,node,p,t_2) && t_2 < t_0
+	    this.solver.add(ctx.mkNot(ctx.mkExists(new Expr[]{n_2,t_2},
+	    				ctx.mkAnd(
+	    						(BoolExpr)nctx.recv.apply(n_2, node.getZ3Node(), p, t_2),
+	    						ctx.mkLt(t_2,t_0)),1,null,null,null,null)));
+
+	//			Constraint 6	there does not exist n_2, t_2 : send(node,n_2,p,t_2) && t_2 < t_0
+	    this.solver.add(ctx.mkNot(ctx.mkExists(new Expr[]{n_2,t_2},
+				ctx.mkAnd(
+						(BoolExpr)nctx.send.apply(node.getZ3Node(), n_2, p, t_2),
+						ctx.mkLt(t_2,t_0)),1,null,null,null,null)));
+
+
+	    result = this.solver.check();
+	    model = null;
+	    assertions = this.solver.getAssertions();
+	    if (result == Status.SATISFIABLE){
+	    	model = this.solver.getModel();
+	    }
+	    this.solver.pop();
+	    return new IsolationResult(ctx,result, p, n_0, t_1, t_0, nctx, assertions, model);
+    	
+    }
+
+    public IsolationResult CheckLinkTraversalProperty (NetworkObject src, NetworkObject dest, NetworkObject le0, NetworkObject le1){
+		assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    solver.push ();
+	    addConstraints();
+
+	    Expr p = ctx.mkConst("check_isolation_p_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    Expr n_1 =ctx.mkConst("check_isolation_n_1_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+
+	    IntExpr t_0 = ctx.mkIntConst("check_isolation_t0_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_1 = ctx.mkIntConst("check_isolation_t1_"+src.getZ3Node()+"_"+dest.getZ3Node());
+	    IntExpr t_2 = ctx.mkIntConst("check_isolation_t2_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p,t_0)
+	    this.solver.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p, t_0));
+
+	//	        Constraint2		send(srcNode,n_1,p1,t_1)
+	    this.solver.add((BoolExpr)nctx.send.apply(src.getZ3Node(), n_1, p, t_1));
+
+	//	        Constraint3		nodeHasAddr(srcNode,p.srcAddr)
+	    this.solver.add((BoolExpr)nctx.nodeHasAddr.apply(src.getZ3Node(), nctx.pf.get("src").apply(p)));
+
+	//	        Constraint4		p.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p), src.getZ3Node()));
+
+	//			Constraint5		∃ t_1, t_2 :
+	    					//	    send(linkNode0,linkNode1,p,t_1) &&
+							//	    recv(linkNode0,linkNode1,p,t_2) &&
+							//	    t_1 < t_0 &&
+							//	    t_2 < t_0
+	    this.solver.add(ctx.mkExists(new Expr[]{t_1,t_2},
+	    				ctx.mkAnd(
+	    						(BoolExpr)nctx.send.apply(le0.getZ3Node(), le1.getZ3Node(), p, t_1),
+	    						(BoolExpr)nctx.recv.apply(le0.getZ3Node(), le1.getZ3Node(), p, t_2),
+	    						ctx.mkLt(t_1,t_0),
+	    						ctx.mkLt(t_2,t_0)),1,null,null,null,null));
+
+
+	    result = this.solver.check();
+	    model = null;
+	    assertions = this.solver.getAssertions();
+	    if (result == Status.SATISFIABLE){
+	    	model = this.solver.getModel();
+	    }
+	    this.solver.pop();
+	    return new IsolationResult(ctx,result, p, n_0, t_1, t_0, nctx, assertions, model);
+
+    }
+
+   public Result CheckDataIsolationPropertyCore (NetworkObject src, NetworkObject dest){
+	   	assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    List<BoolExpr> constr = this.getConstraints();
+	    Expr p = ctx.mkConst("check_isolation_p_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    IntExpr t = ctx.mkIntConst("check_isolation_t_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p,t)
+	    constr.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p, t));
+
+	//	        Constraint2		p.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p), src.getZ3Node()));
+
+	    this.solver.push();
+
+    //     	   Constraint3		for each constraint( n -> constraint)
+	    ArrayList<BoolExpr> names =new ArrayList<BoolExpr>();
+	    for(BoolExpr con : constr){
+	    	BoolExpr n = ctx.mkBoolConst(""+con);
+	    	names.add(n);
+	    	this.solver.add(ctx.mkImplies(n, con));
+	    }
+
+	    BoolExpr[] nam = new BoolExpr[names.size()];
+	    result = this.solver.check(names.toArray(nam));
+	    Result ret =null;
+
+	    if (result == Status.SATISFIABLE){
+	    	System.out.println("SAT");
+	    	ret = new Result(ctx,this.solver.getModel());
+	    }else if(result == Status.UNSATISFIABLE){
+	    	System.out.println("unsat");
+	    	ret = new Result(ctx,this.solver.getUnsatCore());
+	    }
+	    this.solver.pop();
+	    return ret;
+   }
+
+    public DataIsolationResult CheckDataIsolationProperty(NetworkObject src, NetworkObject dest){
+    	assert(net.elements.contains(src));
+	    assert(net.elements.contains(dest));
+	    solver.push ();
+	    addConstraints();
+
+	    Expr p = ctx.mkConst("check_isolation_p_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.packet);
+
+	    Expr n_0 =ctx.mkConst("check_isolation_n_0_"+src.getZ3Node()+"_"+dest.getZ3Node(), nctx.node);
+	    IntExpr t = ctx.mkIntConst("check_isolation_t_"+src.getZ3Node()+"_"+dest.getZ3Node());
+
+	//	        Constraint1		recv(n_0,destNode,p,t)
+	    this.solver.add((BoolExpr)nctx.recv.apply(n_0, dest.getZ3Node(), p, t));
+
+	//	        Constraint2		p.origin == srcNode
+	    this.solver.add(ctx.mkEq(nctx.pf.get("origin").apply(p), src.getZ3Node()));
+
+	    result = this.solver.check();
+	    model = null;
+	    assertions = this.solver.getAssertions();
+	    if (result == Status.SATISFIABLE){
+	    	model = this.solver.getModel();
+	    }
+	    this.solver.pop();
+	    return new DataIsolationResult(ctx,result, p, n_0, t, nctx, assertions, model);
+    }
+
+
+
+
+	public void addConstraints(){
+	    nctx.addConstraints(solver);
+	    net.addConstraints(solver);
+	    for (NetworkObject el : net.elements)
+	        el.addConstraints(solver);
+	}
+
+
+	 public List<BoolExpr> getConstraints(){
+	        Solver l = ctx.mkSolver();
+	        nctx.addConstraints(l);
+	        net.addConstraints(l);
+	        for (NetworkObject el : net.elements)
+	            el.addConstraints(l);
+	        return Arrays.asList(l.getAssertions());
+	}
+}
diff --git a/verigraph/service/src/mcnet/components/Core.java b/verigraph/service/src/mcnet/components/Core.java
new file mode 100644
index 0000000..c72b9e3
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/Core.java
@@ -0,0 +1,44 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.Solver;
+
+/**Core component for everything that matters
+ *
+ */
+public abstract class Core{
+
+		final int MAX_PORT = 512;
+
+	   /**
+	    * Base class for all objects in the modeling framework
+	    * @param ctx
+	    * @param args
+	    */
+	    public Core(Context ctx, Object[]... args){ // Object[]... -> The nearest way to implement variable length argument lists
+	    											//in Java, in the most generic way.
+		    init(ctx,args);
+	    }
+	    /**
+	     * Override _init for any constructor initialization. Avoids having to explicitly call super.__init__ every Time.class
+	     * @param ctx
+	     * @param args
+	     */
+	    abstract protected void init(Context ctx,Object[]... args);
+
+	    /**
+	     * Add constraints to solver
+	     * @param solver
+	     */
+	    abstract protected void addConstraints(Solver solver);
+}
+
+
diff --git a/verigraph/service/src/mcnet/components/DataIsolationResult.java b/verigraph/service/src/mcnet/components/DataIsolationResult.java
new file mode 100644
index 0000000..b90a47f
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/DataIsolationResult.java
@@ -0,0 +1,41 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.Model;
+import com.microsoft.z3.Status;
+
+
+/**Data structure for the response to a check request for data isolation property
+ *
+ */
+public class DataIsolationResult {
+
+	Context ctx;
+	public NetContext nctx;
+	public Status result;
+	public Model model;
+	public Expr violating_packet,last_hop,last_time,t_1;
+	public BoolExpr [] assertions;
+
+	public DataIsolationResult(Context ctx,Status result, Expr violating_packet, Expr last_hop, Expr last_time, NetContext nctx, BoolExpr[] assertions, Model model){
+            this.ctx = ctx;
+            this.result = result;
+            this.violating_packet = violating_packet;
+            this.last_hop = last_hop;
+            this.model = model;
+            this.last_time = last_time;
+            this.assertions = assertions;
+	}
+}
+
diff --git a/verigraph/service/src/mcnet/components/IsolationResult.java b/verigraph/service/src/mcnet/components/IsolationResult.java
new file mode 100644
index 0000000..1ecaccc
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/IsolationResult.java
@@ -0,0 +1,42 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.Model;
+import com.microsoft.z3.Status;
+
+/**
+ * Data structure for the response to check requests for isolation properties
+ *
+ */
+public class IsolationResult {
+
+	Context ctx;
+	public NetContext nctx;
+	public Status result;
+	public Model model;
+	public Expr violating_packet,last_hop,last_send_time,last_recv_time,t_1;
+	public BoolExpr [] assertions;
+
+	public IsolationResult(Context ctx,Status result, Expr violating_packet, Expr last_hop, Expr last_send_time, Expr last_recv_time,NetContext nctx, BoolExpr[] assertions, Model model){
+            this.ctx = ctx;
+            this.result = result;
+            this.violating_packet = violating_packet;
+            this.last_hop = last_hop;
+            this.model = model;
+            this.last_send_time = last_send_time;
+            this.last_recv_time = last_recv_time;
+            this.assertions = assertions;
+	}
+}
+
diff --git a/verigraph/service/src/mcnet/components/NetContext.java b/verigraph/service/src/mcnet/components/NetContext.java
new file mode 100644
index 0000000..ece31c5
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/NetContext.java
@@ -0,0 +1,340 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Constructor;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.DatatypeSort;
+import com.microsoft.z3.EnumSort;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Sort;
+
+import mcnet.netobjs.DumbNode;
+
+/**
+ * Basic fields and other things required for model checking.
+ *
+ */
+public class NetContext extends Core{
+
+
+		List<BoolExpr> constraints; 
+		List<Core> policies;
+
+	    public HashMap<String,NetworkObject> nm; //list of nodes, callable by node name
+	    public HashMap<String,DatatypeExpr> am; // list of addresses, callable by address name
+	    public HashMap<String,FuncDecl> pf;
+	    Context ctx;
+	    public EnumSort node,address;
+	    public FuncDecl src_port,dest_port,nodeHasAddr,addrToNode,send,recv;
+	    public DatatypeSort packet;
+
+	    /*	   Constants definition
+	        - used in the packet proto field */
+	   	public final int HTTP_REQUEST    = 1;
+	   	public final int HTTP_RESPONSE   = 2;
+	   	public final int POP3_REQUEST    = 3;
+	   	public final int POP3_RESPONSE   = 4;
+
+		/**
+		 * Context for all of the rest that follows. Every network needs one of these
+		 * @param ctx
+		 * @param args
+		 */
+	   	public NetContext(Context ctx,Object[]... args ){
+	   		super(ctx,args);
+
+	   	}
+
+	   	@Override
+		protected void init(Context ctx, Object[]... args) {
+	   		this.ctx = ctx;
+	        nm = new HashMap<String,NetworkObject>(); //list of nodes, callable by node name
+		    am = new HashMap<String,DatatypeExpr>(); // list of addresses, callable by address name
+		    pf= new HashMap<String,FuncDecl>() ;
+
+		    mkTypes((String[])args[0],(String[])args[1]);
+
+	   		constraints = new ArrayList<BoolExpr>();
+	        policies = new ArrayList<Core>();
+
+	        baseCondition();
+		}
+
+	    /**
+	     * A policy is a collection of shared algorithms or functions used by multiple components
+	     * (for instance compression or DPI policies etc).
+	     * @param policy
+	     */
+	    public void AddPolicy (NetworkObject policy){
+	        policies.add(policy);
+	    }
+
+		@Override
+		protected void addConstraints(Solver solver) {
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+		    solver.add(constraints.toArray(constr));
+	        for (Core policy : policies){
+	            policy.addConstraints(solver);
+	        }
+		}
+
+	    private void mkTypes (String[] nodes, String[] addresses){
+	        //Nodes in a network
+	        node = ctx.mkEnumSort("Node", nodes);
+	        for(int i=0;i<node.getConsts().length;i++){
+	    		DatatypeExpr fd  = (DatatypeExpr)node.getConst(i);
+	    		DumbNode dn =new DumbNode(ctx,new Object[]{fd});
+	    		nm.put(fd.toString(),dn);
+	    	}
+
+	        //Addresses for this network
+	        String[] new_addr = new String[addresses.length+1];
+	        for(int k=0;k<addresses.length;k++)
+	        	new_addr[k] = addresses[k];
+
+	        new_addr[new_addr.length-1] = "null";
+	    	address = ctx.mkEnumSort("Address", new_addr);
+	    	for(int i=0;i<address.getConsts().length;i++){
+	    		DatatypeExpr fd  = (DatatypeExpr)address.getConst(i);
+	    		am.put(fd.toString(),fd);
+	    	}
+
+	        // Type for packets, contains (some of these are currently represented as relations):
+	        // -   src: Source address
+	        // -   dest: Destination address
+	        // -   origin: Node where the data originated. (Node)
+	        // -   body: Packet contents. (Integer)
+	        // -   seq: Sequence number for packets. (Integer)
+	        // -   options: A representation for IP options. (Integer)
+
+	        String[] fieldNames = new String[]{
+	        		"src","dest","inner_src","inner_dest","origin","orig_body","body","seq","proto","emailFrom","url","options","encrypted"};
+	        Sort[] srt = new Sort[]{
+	        		address,address,address,address,node,ctx.mkIntSort(),ctx.mkIntSort(),ctx.mkIntSort(),
+	        		ctx.mkIntSort(),ctx.mkIntSort(),ctx.mkIntSort(),ctx.mkIntSort(),ctx.mkBoolSort()};
+	        Constructor packetcon = ctx.mkConstructor("packet", "is_packet", fieldNames, srt, null);
+	        packet = ctx.mkDatatypeSort("packet",  new Constructor[] {packetcon});
+
+	        for(int i=0;i<fieldNames.length;i++){
+	        	pf.put(fieldNames[i], packet.getAccessors()[0][i]); // pf to get packet's function declarations by name
+		    }
+
+	        src_port = ctx.mkFuncDecl("sport", packet, ctx.mkIntSort());
+	        dest_port = ctx.mkFuncDecl("dport", packet, ctx.mkIntSort());
+
+	        // Some commonly used relations
+
+	        // nodeHasAddr: node -> address -> boolean
+	        nodeHasAddr = ctx.mkFuncDecl("nodeHasAddr", new Sort[]{node, address},ctx.mkBoolSort());
+
+	        // addrToNode: address -> node
+	        addrToNode = ctx.mkFuncDecl("addrToNode", address, node);
+
+	        // Send and receive both have the form:
+	        // source-> destination -> packet-> int-> bool
+
+	        // send: node -> node -> packet-> int-> bool
+	        send = ctx.mkFuncDecl("send", new Sort[]{ node, node, packet, ctx.mkIntSort()},ctx.mkBoolSort());
+
+	        // recv: node -> node -> packet-> int-> bool
+	        recv = ctx.mkFuncDecl("recv", new Sort[]{ node, node, packet, ctx.mkIntSort()},ctx.mkBoolSort());
+
+	    }
+
+	    /**
+	     * Set up base conditions for the network
+	     */
+	    private void baseCondition(){
+	    	// Basic constraints for the overall model
+	        Expr n_0 = ctx.mkConst("ctx_base_n_0", node);
+	        Expr n_1 = ctx.mkConst("ctx_base_n_1", node);
+	        Expr n_2 = ctx.mkConst("ctx_base_n_2", node);
+	        Expr p_0 = ctx.mkConst("ctx_base_p_0", packet);
+	        Expr p_1 = ctx.mkConst("ctx_base_p_1", packet);
+	        IntExpr t_0 = ctx.mkIntConst("ctx_base_t_0");
+	        IntExpr t_1 = ctx.mkIntConst("ctx_base_t_1");
+
+	        // Constraint1 		send(n_0, n_1, p_0, t_0) -> n_0 != n_1
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)send.apply(n_0, n_1, p_0, t_0),ctx.mkNot(ctx.mkEq( n_0, n_1))),1,null,null,null,null));
+
+	        // Constraint2 		recv(n_0, n_1, p_0, t_0) -> n_0 != n_1
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),ctx.mkNot(ctx.mkEq( n_0, n_1))),1,null,null,null,null));
+
+	        // Constraint3 		send(n_0, n_1, p_0, t_0) -> p_0.src != p_0.dest
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    		ctx.mkNot(ctx.mkEq(  pf.get("src").apply(p_0), pf.get("dest").apply(p_0)))),1,null,null,null,null));
+
+	        // Constraint4 		recv(n_0, n_1, p_0, t_0) -> p_0.src != p_0.dest
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                    		ctx.mkNot(ctx.mkEq(pf.get("src").apply(p_0),pf.get("dest").apply(p_0)))),1,null,null,null,null));
+
+	        // Constraint5 		recv(n_0, n_1, p, t_0) -> send(n_0, n_1, p, t_1) && t_1 < t_0
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                                ctx.mkExists(new Expr[]{t_1},
+	                                   ctx.mkAnd((BoolExpr)send.apply(n_0, n_1, p_0, t_1),
+	                                        ctx.mkLt(t_1, t_0)),1,null,null,null,null)),1,null,null,null,null));
+
+	        // Constraint6 		send(n_0, n_1, p, t_0) -> p.src_port > 0 && p.dest_port < MAX_PORT
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    		ctx.mkAnd( 	ctx.mkGe((IntExpr)src_port.apply(p_0),(IntExpr)ctx.mkInt(0)),
+	                    				 	ctx.mkLt((IntExpr)src_port.apply(p_0),(IntExpr) ctx.mkInt(MAX_PORT)))),1,null,null,null,null));
+
+	        // Constraint7 		recv(n_0, n_1, p, t_0) -> p.src_port > 0 && p.dest_port < MAX_PORT
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                    	ctx.mkAnd( 	ctx.mkGe((IntExpr)dest_port.apply(p_0),(IntExpr)ctx.mkInt(0)),
+	                    				ctx.mkLt((IntExpr)dest_port.apply(p_0),(IntExpr) ctx.mkInt(MAX_PORT)))),1,null,null,null,null));
+
+	        // Constraint8 		recv(n_0, n_1, p_0, t_0) -> t_0 > 0
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                                  ctx.mkGt(t_0,ctx.mkInt(0))),1,null,null,null,null));
+
+	        // Constraint9 		send(n_0, n_1, p_0, t_0) -> t_0 > 0
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    		ctx.mkGt(t_0,ctx.mkInt(0))),1,null,null,null,null));
+
+	        // Extra constriants for supporting the VPN gateway
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkNot(ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.am.get("null")))),
+	                    	ctx.mkNot(ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0)))),1,null,null,null,null));
+
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.am.get("null"))),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0))),1,null,null,null,null));
+
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkEq(this.pf.get("inner_dest").apply(p_0), this.am.get("null"))),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0))),1,null,null,null,null));
+
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkNot(ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.am.get("null")))),
+	                    			  ctx.mkNot(ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0)))),1,null,null,null,null));
+
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.am.get("null"))),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0))),1,null,null,null,null));
+
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0},
+	                    ctx.mkImplies(
+	                    	ctx.mkAnd((BoolExpr)recv.apply(n_0, n_1, p_0, t_0),
+	                    			  ctx.mkEq(this.pf.get("inner_dest").apply(p_0), this.am.get("null"))),
+	                    			  ctx.mkEq(this.pf.get("inner_src").apply(p_0), this.pf.get("inner_dest").apply(p_0))),1,null,null,null,null));
+
+	        constraints.add(
+	        		ctx.mkForall(new Expr[]{n_0, n_1, p_0, t_0, n_2, p_1, t_1},
+	        			ctx.mkImplies(
+	        				ctx.mkAnd(
+	        					ctx.mkLt(t_1, t_0),
+	        					(BoolExpr)send.apply(n_0, n_1, p_0, t_0),
+	        					(BoolExpr)this.pf.get("encrypted").apply(p_1),
+	        					(BoolExpr)recv.apply(n_2, n_0, p_1, t_1),
+	        					(BoolExpr)this.pf.get("encrypted").apply(p_0)),
+	        				ctx.mkAnd(
+	        					ctx.mkEq(this.pf.get("inner_src").apply(p_1), this.pf.get("inner_src").apply(p_0)),
+	        					ctx.mkEq(this.pf.get("inner_dest").apply(p_1), this.pf.get("inner_dest").apply(p_0)),
+	        					ctx.mkEq(this.pf.get("origin").apply(p_1), this.pf.get("origin").apply(p_0)),
+							    ctx.mkEq(this.pf.get("orig_body").apply(p_1), this.pf.get("orig_body").apply(p_0)),
+							    ctx.mkEq(this.pf.get("body").apply(p_1), this.pf.get("body").apply(p_0)),
+							    ctx.mkEq(this.pf.get("seq").apply(p_1), this.pf.get("seq").apply(p_0)),
+							    ctx.mkEq(this.pf.get("proto").apply(p_1), this.pf.get("proto").apply(p_0)),
+							    ctx.mkEq(this.pf.get("emailFrom").apply(p_1), this.pf.get("emailFrom").apply(p_0)),
+							    ctx.mkEq(this.pf.get("url").apply(p_1), this.pf.get("url").apply(p_0)),
+							    ctx.mkEq(this.pf.get("options").apply(p_1), this.pf.get("options").apply(p_0)))),1,null,null,null,null)
+	        		);
+	    }
+
+	    /**
+	     * Two packets have equal headers
+	     * @param p1
+	     * @param p2
+	     * @return
+	     */
+	    public BoolExpr PacketsHeadersEqual(Expr p1, Expr p2){
+	        return ctx.mkAnd(new BoolExpr[]{
+	        		ctx.mkEq(pf.get("src").apply(p1), 		pf.get("src").apply(p2)),
+	        		ctx.mkEq(pf.get("dest").apply(p1), 		pf.get("dest").apply(p2)),
+					ctx.mkEq(pf.get("origin").apply(p1), 	pf.get("origin").apply(p2)),
+					ctx.mkEq(pf.get("seq").apply(p1), 		pf.get("seq").apply(p2)),
+					ctx.mkEq(src_port.apply(p1),			src_port.apply(p2)),
+					ctx.mkEq(dest_port.apply(p1), 			dest_port.apply(p2)),
+					ctx.mkEq(pf.get("options").apply(p1),	pf.get("options").apply(p2))});
+		}
+
+	    /**
+	     * Two packets have equal bodies
+	     * @param p1
+	     * @param p2
+	     * @return
+	     */
+	    public BoolExpr PacketContentEqual(Expr p1, Expr p2){
+	        return ctx.mkEq(pf.get("body").apply(p1), 		pf.get("body").apply(p2));
+		}
+
+
+	  /* seems to be useless
+	   *
+	public Function failurePredicate (NetContext context)
+	{
+	    return (NetworkObject node) -> ctx.mkNot(context.failed (node.z3Node));
+
+	}*/
+
+	public BoolExpr destAddrPredicate (Expr p, DatatypeExpr address){
+		return  ctx.mkEq(pf.get("dest").apply(p),address);
+	}
+
+	public  BoolExpr srcAddrPredicate (Expr p, DatatypeExpr address){
+		return  ctx.mkEq(pf.get("src").apply(p),address);
+	}
+
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/components/Network.java b/verigraph/service/src/mcnet/components/Network.java
new file mode 100644
index 0000000..c04f771
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/Network.java
@@ -0,0 +1,296 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Z3Exception;
+
+/**Model for a network, encompasses routing and wiring
+ * 
+ */
+public class Network extends Core{
+
+	Context ctx;
+	NetContext nctx;
+	List<BoolExpr> constraints; 
+	List<NetworkObject> elements;
+
+
+
+	public Network(Context ctx,Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		this.nctx = (NetContext) args[0][0];
+        constraints = new ArrayList<BoolExpr>();
+        elements = new ArrayList<NetworkObject>();
+
+	}
+
+	/**Composes the network linking the configured network objects
+	 *
+	 * @param elements
+	 */
+	public void attach (NetworkObject ... elements){
+	      for(NetworkObject el : elements)
+		  this.elements.add(el);
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		try {
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+		    solver.add(constraints.toArray(constr));
+		} catch (Z3Exception e) {
+			e.printStackTrace();
+		}
+	}
+
+	/**
+	 * Specify host to address mapping.
+	 * Handles the case in which we have more than one address for a node
+	 * @param addrmap
+	 */
+	 public void setAddressMappings(ArrayList<Tuple<NetworkObject,ArrayList<DatatypeExpr>>> addrmap){
+		 // Set address mapping for nodes.
+		 for (Tuple<NetworkObject,ArrayList<DatatypeExpr>> entry : addrmap) {
+	    	    NetworkObject node=entry._1;
+	    	    List<DatatypeExpr> addr=entry._2;
+	            Expr a_0 = ctx.mkConst(node+"_address_mapping_a_0",nctx.address);
+	   		    ArrayList<BoolExpr> or_clause = new ArrayList<BoolExpr>();
+
+	   		   // Constraint 1 			addrToNode(foreach ad in addr) = node
+	    	    for (DatatypeExpr ad : addr){
+	              constraints.add(ctx.mkEq(nctx.addrToNode.apply(ad), node.getZ3Node()));
+	              or_clause.add(ctx.mkEq(a_0,ad));
+		        }
+	            BoolExpr[] orClause = new BoolExpr[or_clause.size()];
+
+	            // Constraint 2			nodeHasAddr(node, a_0) == Or(foreach ad in addr (a_0 == ad))
+	        	// Note we need the iff here to make sure that we set nodeHasAddr to false
+		        // for other addresses.
+	            constraints.add(ctx.mkForall(new Expr[]{a_0},
+	                  ctx.mkEq(ctx.mkOr(or_clause.toArray(orClause)), nctx.nodeHasAddr.apply(node.getZ3Node(), a_0)),1,null,null,null,null));
+			}
+	 }
+
+
+
+	/**
+	 * Don't forward packets addressed to node
+	 * @param node
+	 */
+	 public void saneSend(NetworkObject node){
+	     Expr n_0 = ctx.mkConst(node+"_saneSend_n_0", nctx.node);
+	     Expr p_0 = ctx.mkConst(node+"_saneSend_p_0", nctx.packet);
+	     IntExpr t_0 = ctx.mkIntConst(node+"_saneSend_t_0");
+	     	// Constant: node
+	        //Constraint	 send(node, n_0, p, t_0) -> !nodeHasAddr(node, p.dest)
+	        constraints.add(
+	                ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	                    ctx.mkImplies((BoolExpr)nctx.send.apply(node.getZ3Node(),n_0, p_0, t_0),
+	                    		ctx.mkNot((BoolExpr)nctx.nodeHasAddr.apply( node.getZ3Node(),
+	                    				nctx.pf.get("dest").apply(p_0)))),1,null,null,null,null));
+	    }
+
+	 /**
+	  * Node sends all traffic through gateway
+	  * @param node
+	  * @param gateway
+	  */
+	  public void setGateway (NetworkObject node, NetworkObject gateway){
+	        // SetGateway(self, node, gateway): All packets from node are sent through gateway
+	        Expr n_0 = ctx.mkConst(node+"_gateway_n_0", nctx.node);
+	        Expr p_0 = ctx.mkConst(node+"_gateway_p_0", nctx.packet);
+	        IntExpr t_0 = ctx.mkIntConst(node+"_gateway_t_0");
+
+	        //Constraint	 send(node, n_0, p_0, t_0) -> n_0 = gateway
+	        constraints.add(
+	        		 ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	        				 ctx.mkImplies(
+	        						 (BoolExpr)nctx.send.apply(node.getZ3Node(), n_0, p_0, t_0),
+	                                           ctx.mkEq(n_0,gateway.getZ3Node())),1,null,null,null,null));
+
+//	        constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//	            ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0, node.getZ3Node(),  p_0, t_0),
+//	                                            ctx.mkEq(n_0,gateway.getZ3Node())),1,null,null,null,null));
+	  }
+
+	  /**
+	   * Assigns a specific routing table to a network object. Routing entries in the form: address -> node
+	   * @param node
+	   * @param routing_table
+	   */
+       public void routingTable (NetworkObject node,ArrayList<Tuple<DatatypeExpr,NetworkObject>> routing_table){
+	       compositionPolicy(node,routing_table);
+	   }
+
+       /**
+        * Composition policies steer packets between middleboxes.
+        * @param node
+        * @param policy
+        */
+       public void compositionPolicy (NetworkObject node,ArrayList<Tuple<DatatypeExpr,NetworkObject>> policy){
+	        //Policy is of the form predicate -> node
+	    	Expr p_0 = ctx.mkConst(node+"_composition_p_0", nctx.packet);
+	    	Expr n_0 = ctx.mkConst(node+"_composition_n_0", nctx.node);
+	    	Expr t_0 = ctx.mkIntConst(node+"_composition_t_0");
+
+	    	HashMap<String,ArrayList<BoolExpr>> collected = new HashMap<String,ArrayList<BoolExpr>>();
+	        HashMap<String,NetworkObject> node_dict = new HashMap<String,NetworkObject>();
+            BoolExpr predicates;
+            for(int y=0;y<policy.size();y++){
+            	Tuple<DatatypeExpr,NetworkObject> tp = policy.get(y);
+            	if(collected.containsKey(""+tp._2))	 collected.get(""+tp._2).add(nctx.destAddrPredicate(p_0,tp._1));
+            	else{
+            		ArrayList<BoolExpr> alb = new ArrayList<BoolExpr>();
+            		alb.add(nctx.destAddrPredicate(p_0,tp._1));
+            		collected.put(""+tp._2,alb);
+            	}
+            	node_dict.put(""+tp._2, tp._2);
+            }
+
+    	    //Constraint		foreach rtAddr,rtNode in rt( send(node, n_0, p_0, t_0) &&
+    	    //					Or(foreach rtAddr in rt destAddrPredicate(p_0,rtAddr)) -> n_0 == rtNode )
+    	 	for (Map.Entry<String,ArrayList<BoolExpr>> entry : collected.entrySet()) {
+         		BoolExpr[] pred = new BoolExpr[entry.getValue().size()];
+        	    predicates = ctx.mkOr(entry.getValue().toArray(pred));
+
+        	    constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(node.getZ3Node(), n_0, p_0, t_0), predicates),
+                                ctx.mkEq(n_0, node_dict.get(entry.getKey()).getZ3Node())),1,null,null,null,null));
+         	}
+        }
+
+	    /**
+	     * Routing entries are in the form: address -> node. Also allows packet to be sent to another box for further processing
+	     * @param node
+	     * @param routing_table
+	     * @param shunt_node
+	     */
+	   public void routingTableShunt (NetworkObject node,ArrayList<Tuple<DatatypeExpr,NetworkObject>> routing_table,NetworkObject shunt_node){
+	    	   compositionPolicyShunt(node,routing_table,shunt_node);
+	   	    }
+
+	    /**
+	     * Composition policies steer packets between middleboxes.Policy is in the form: predicate -> node
+	     * @param node
+	     * @param routing_table
+	     * @param shunt_node
+	     */
+	   public void compositionPolicyShunt (NetworkObject node,ArrayList<Tuple<DatatypeExpr,NetworkObject>> routing_table,NetworkObject shunt_node){
+		    Expr p_0 = ctx.mkConst(node+"_composition_p_0", nctx.packet);
+	    	Expr n_0 = ctx.mkConst(node+"_composition_n_0", nctx.node);
+	    	Expr t_0 = ctx.mkIntConst(node+"_composition_t_0");
+
+	    	HashMap<String,ArrayList<BoolExpr>> collected = new HashMap<String,ArrayList<BoolExpr>>();
+	        HashMap<String,NetworkObject> node_dict = new HashMap<String,NetworkObject>();
+	        BoolExpr predicates;
+            for(int y=0;y<routing_table.size();y++){
+            	Tuple<DatatypeExpr,NetworkObject> tp = routing_table.get(y);
+            	if(collected.containsKey(""+tp._2))	 collected.get(""+tp._2).add(nctx.destAddrPredicate(p_0,tp._1));
+            	else{
+            		ArrayList<BoolExpr> alb = new ArrayList<BoolExpr>();
+            		alb.add(nctx.destAddrPredicate(p_0,tp._1));
+            		collected.put(""+tp._2,alb);
+            	}
+            	node_dict.put(""+tp._2, tp._2);
+            }
+
+            //Constraint		foreach rtAddr,rtNode in rt( send(node, n_0, p_0, t_0) &&
+            //					Or(foreach rtAddr in rt destAddrPredicate(p_0,rtAddr)) -> n_0 == rtNode )
+         	for (Map.Entry<String,ArrayList<BoolExpr>> entry : collected.entrySet()) {
+        	    BoolExpr[] pred = new BoolExpr[entry.getValue().size()];
+        	    predicates = ctx.mkOr(entry.getValue().toArray(pred));
+
+        	    constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(node.getZ3Node(), n_0, p_0, t_0), predicates),
+                               ctx.mkOr(ctx.mkEq(n_0, node_dict.get(entry.getKey()).getZ3Node()),ctx.mkEq(n_0, shunt_node.getZ3Node()))),1,null,null,null,null));
+         	}
+
+	    }
+
+//	    public void SimpleIsolation (NetworkObject node, ArrayList<DatatypeExpr> addresses){
+//	       Expr p = ctx.mkConst(node+"_s_p", nctx.packet);
+//	       Expr n = ctx.mkConst(node+"_s_n", nctx.node);
+//	       IntExpr t = ctx.mkInt(node+"_s_t");
+//
+//	       BoolExpr[] a_pred= new BoolExpr[addresses.size()];
+//	        for(int y=0;y<addresses.size();y++){
+//	        	DatatypeExpr de = addresses.get(y);
+//	        	a_pred[y] = ctx.mkOr(ctx.mkEq(nctx.pf.get("src").apply(p), de),ctx.mkEq(nctx.pf.get("dest").apply(p), de));
+//	        }
+//
+//	        constraints.add(
+//	                ctx.mkForall(new Expr[]{p, n, t},
+//	                  ctx.mkImplies((BoolExpr)nctx.recv.apply(n, node.getZ3Node(), p, t),
+//	                            ctx.mkOr(a_pred)),1,null,null,null,null));
+//	        constraints.add(
+//	                ctx.mkForall(new Expr[]{p, n, t},
+//	                  ctx.mkImplies((BoolExpr)nctx.send.apply(node.getZ3Node(), n, p, t),
+//	                            ctx.mkOr(a_pred)),1,null,null,null,null));
+//	    }
+
+
+	   /**
+	    * Set isolation constraints on a node.
+	    * Doesn't need to be set but useful when interfering policies are in play.
+	    * @param node
+	    * @param adjacencies
+	    *
+	    */
+	   public void SetIsolationConstraint ( NetworkObject node,  ArrayList<NetworkObject> adjacencies){
+
+		   	Expr n_0 = ctx.mkConst(node+"_isolation_n_0", nctx.node);
+	        Expr p_0 = ctx.mkConst(node+"_isolation_p_0", nctx.packet);
+	        IntExpr t_0 = ctx.mkInt(node+"_isolation_t_0");
+
+	        BoolExpr[] adj = new BoolExpr[adjacencies.size()];
+	        for(int y=0;y<adjacencies.size();y++){
+	        	NetworkObject no = adjacencies.get(y);
+	        	adj[y] =  ctx.mkEq(n_0,no.getZ3Node());
+	        }
+	        BoolExpr clause = ctx.mkOr(adj);
+
+	        constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	            ctx.mkImplies((BoolExpr)nctx.send.apply(node.getZ3Node(), n_0, p_0, t_0),
+	                                    clause),1,null,null,null,null));
+	        constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	            ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0, node.getZ3Node(), p_0, t_0),
+	                                    clause),1,null,null,null,null));
+	       }
+
+	  /**
+	   * Return all currently attached endhosts
+	   * @return NetworkObject
+	   */
+	   public List<String> EndHosts(){
+		   List<String> att_nos = new ArrayList<String>();
+		   for(NetworkObject el :elements){
+			   if(el.isEndHost){
+				   System.out.println("el: "+el);
+			   		att_nos.add(el.getZ3Node().toString());
+		   		}
+		   	}
+	        return att_nos;
+	   }
+}
diff --git a/verigraph/service/src/mcnet/components/NetworkObject.java b/verigraph/service/src/mcnet/components/NetworkObject.java
new file mode 100644
index 0000000..0de3937
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/NetworkObject.java
@@ -0,0 +1,57 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+
+/** Represents a generic network object.
+ *
+ */
+public abstract class NetworkObject extends Core{
+
+	public NetworkObject(Context ctx,Object[]... args) {
+		super(ctx,args);
+	}
+
+	protected DatatypeExpr z3Node;
+	protected boolean isEndHost;
+	/**
+	 * Get a reference to the z3 node this class wraps around
+	 * @return
+	 */
+	abstract public DatatypeExpr getZ3Node();
+
+	public String toString(){
+	        return z3Node.toString();
+	}
+
+	//There is probably an error: z3Node.hashCode = 0 because AST.hashCode() has always hash=0
+	/*public int hashCode(){
+		return z3Node.hashCode();
+	}*/
+
+	/**
+	 * A simple way to determine the set of endhosts
+	 * @return
+	 */
+	public boolean isEndHost(){
+	    return isEndHost;
+	}
+
+	/**
+	 * Wrap methods to set policy
+	 * @param policy
+	 * @throws UnsupportedOperationException
+	 */
+	void setPolicy (Object policy) throws UnsupportedOperationException{
+	     throw new UnsupportedOperationException();
+	}
+}
diff --git a/verigraph/service/src/mcnet/components/Result.java b/verigraph/service/src/mcnet/components/Result.java
new file mode 100644
index 0000000..acb23f1
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/Result.java
@@ -0,0 +1,43 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.Model;
+
+/**Data structure for the core of the response to a check request for data isolation property
+ *
+ */
+public class Result {
+	Context ctx;
+	public Model model;
+	public BoolExpr[] unsat_core;
+
+/**
+ *
+ * @param ctx
+ * @param model
+ */
+    public Result(Context ctx, Model model){
+            this.ctx = ctx;
+            this.model = model;
+	}
+
+/**
+ *
+ * @param ctx
+ * @param unsat_core
+ */
+    public Result(Context ctx, BoolExpr[] unsat_core){
+        this.ctx = ctx;
+        this.unsat_core = unsat_core;
+}
+}
diff --git a/verigraph/service/src/mcnet/components/Tuple.java b/verigraph/service/src/mcnet/components/Tuple.java
new file mode 100644
index 0000000..849d607
--- /dev/null
+++ b/verigraph/service/src/mcnet/components/Tuple.java
@@ -0,0 +1,35 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.components;
+
+/** A data structure which is an utility to make a generic couple of objects with different types in Java
+ *
+ */
+public class Tuple<T, U> {
+	  public final T _1;
+	  public final U _2;
+
+
+	  public Tuple(T arg1,U arg2) {
+	    super();
+	    this._1 = arg1;
+	    this._2 = arg2;
+	  }
+
+	  public Tuple(){
+		  this._1 = null;
+		    this._2 = null;
+	  }
+
+	  @Override
+	  public String toString() {
+	    return String.format("(%s, %s)", _1, _2);
+	  }
+	}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/AclFirewall.java b/verigraph/service/src/mcnet/netobjs/AclFirewall.java
new file mode 100644
index 0000000..4ae3421
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/AclFirewall.java
@@ -0,0 +1,123 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Sort;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+import mcnet.components.Tuple;
+
+/** Represents a Firewall with the associated Access Control List
+ *
+ */
+public class AclFirewall extends NetworkObject{
+
+	List<BoolExpr> constraints;
+	Context ctx;
+	DatatypeExpr fw;
+	ArrayList<Tuple<DatatypeExpr,DatatypeExpr>> acls;
+	Network net;
+	NetContext nctx;
+	FuncDecl acl_func;
+
+	public AclFirewall(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		isEndHost=false;
+   		constraints = new ArrayList<BoolExpr>();
+   		acls = new ArrayList<Tuple<DatatypeExpr,DatatypeExpr>>();
+   		z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+        fw = z3Node;
+	    net = (Network)args[0][1];
+	    nctx = (NetContext)args[0][2];
+	    net.saneSend(this);
+		firewallSendRules();
+	}
+
+	/**
+	 * Wrap add acls
+	 * @param policy
+	 */
+	public void setPolicy(ArrayList<Tuple<DatatypeExpr, DatatypeExpr>> policy){
+		addAcls(policy);
+	}
+
+	public void addAcls(ArrayList<Tuple<DatatypeExpr,DatatypeExpr>> acls){
+		this.acls.addAll(acls);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return fw;
+	}
+
+
+	@Override
+	protected void addConstraints(Solver solver) {
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+		    solver.add(constraints.toArray(constr));
+		    aclConstraints(solver);
+	}
+
+    private void firewallSendRules (){
+    	Expr p_0 = ctx.mkConst(fw+"_firewall_send_p_0", nctx.packet);
+    	Expr n_0 = ctx.mkConst(fw+"_firewall_send_n_0", nctx.node);
+    	Expr n_1 = ctx.mkConst(fw+"_firewall_send_n_1", nctx.node);
+    	IntExpr t_0 = ctx.mkIntConst(fw+"_firewall_send_t_0");
+    	IntExpr t_1 = ctx.mkIntConst(fw+"_firewall_send_t_1");
+    	acl_func = ctx.mkFuncDecl(fw+"_acl_func", new Sort[]{nctx.address, nctx.address},ctx.mkBoolSort());
+
+    	//Constraint1		send(fw, n_0, p, t_0)  -> (exist n_1,t_1 : (recv(n_1, fw, p, t_1) &&
+    	//    				t_1 < t_0 && !acl_func(p.src,p.dest))
+    	constraints.add(
+        	ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	            ctx.mkImplies(
+	            	(BoolExpr)nctx.send.apply(new Expr[]{ fw, n_0, p_0, t_0}),
+	            	ctx.mkExists(new Expr[]{t_1},
+	            			ctx.mkAnd(ctx.mkLt(t_1,t_0),
+	            						ctx.mkExists(new Expr[]{n_1},
+	            								nctx.recv.apply(n_1, fw, p_0, t_1),1,null,null,null,null),
+	            						ctx.mkNot((BoolExpr)acl_func.apply(nctx.pf.get("src").apply(p_0), nctx.pf.get("dest").apply(p_0)))),1,null,null,null,null)),1,null,null,null,null));
+
+    }
+
+    private void aclConstraints(Solver solver){
+    	if (acls.size() == 0)
+            return;
+        Expr a_0 = ctx.mkConst(fw+"_firewall_acl_a_0", nctx.address);
+        Expr a_1 = ctx.mkConst(fw+"_firewall_acl_a_1", nctx.address);
+        BoolExpr[] acl_map = new BoolExpr[acls.size()];
+        for(int y=0;y<acls.size();y++){
+        	Tuple<DatatypeExpr,DatatypeExpr> tp = acls.get(y);
+        	acl_map[y] = ctx.mkOr(ctx.mkAnd(ctx.mkEq(a_0,tp._1),ctx.mkEq(a_1,tp._2)), ctx.mkAnd(ctx.mkEq(a_0,tp._2),ctx.mkEq(a_1,tp._1)));
+        }
+        //Constraint2		acl_func(a_0,a_1) == or(foreach ip1,ip2 in acl_map ((a_0 == ip1 && a_1 == ip2)||(a_0 == ip2 && a_1 == ip1)))
+        solver.add(ctx.mkForall(new Expr[]{a_0, a_1},
+        						ctx.mkEq(
+        								acl_func.apply(a_0, a_1),
+        								ctx.mkOr(acl_map)),1,null,null,null,null));
+    }
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/DumbNode.java b/verigraph/service/src/mcnet/netobjs/DumbNode.java
new file mode 100644
index 0000000..012ff40
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/DumbNode.java
@@ -0,0 +1,42 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetworkObject;
+
+/**
+ * This is just a wrapper around z3 instances. The idea is that by using this we perhaps need to have
+ * fewer (or no) ifs to deal with the case where we don't instantiate an object for a node
+ *
+ */
+public class DumbNode extends NetworkObject {
+	public DumbNode(Context ctx, Object[]... args){
+		super(ctx,args);
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		return;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		isEndHost=true;
+		this.z3Node = (DatatypeExpr)args[0][0];
+	}
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return z3Node;
+	}
+}
diff --git a/verigraph/service/src/mcnet/netobjs/EndHost.java b/verigraph/service/src/mcnet/netobjs/EndHost.java
new file mode 100644
index 0000000..99cf732
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/EndHost.java
@@ -0,0 +1,100 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**
+ * End host network objects
+ *
+ */
+public class EndHost extends NetworkObject{
+
+	List<BoolExpr> constraints;
+	Context ctx;
+	DatatypeExpr node;
+	Network net;
+	NetContext nctx;
+
+	public EndHost(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		isEndHost=true;
+   		constraints = new ArrayList<BoolExpr>();
+        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+        node = z3Node;
+        net = (Network)args[0][1];
+        nctx = (NetContext)args[0][2];
+		endHostRules();
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return node;
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+		    solver.add(constraints.toArray(constr));
+	}
+
+    public void endHostRules (){
+    	Expr n_0 = ctx.mkConst("eh_"+node+"_n_0", nctx.node);
+        IntExpr t_0 = ctx.mkIntConst("eh_"+node+"_t_0");
+        Expr p_0 = ctx.mkConst("eh_"+node+"_p_0", nctx.packet);
+
+        //Constraint1		send(node, n_0, p, t_0) -> nodeHasAddr(node,p.src)
+        constraints.add(
+        	ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	            ctx.mkImplies(
+	            	(BoolExpr)nctx.send.apply(	new Expr[]{ node, n_0, p_0, t_0}),
+	            	(BoolExpr)nctx.nodeHasAddr.apply(new Expr[]{node, nctx.pf.get("src").apply(p_0)})),1,null,null,null,null));
+        //Constraint2		send(node, n_0, p, t_0) -> p.origin == node
+        constraints.add(
+        	ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                ctx.mkImplies(
+                		(BoolExpr)nctx.send.apply(	new Expr[]{ node, n_0, p_0, t_0}),
+                		ctx.mkEq(nctx.pf.get("origin").apply(p_0),node)),1,null,null,null,null));
+        //Constraint3      send(node, n_0, p, t_0) -> p.orig_body == p.body
+        constraints.add(
+        	ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                ctx.mkImplies(
+                		(BoolExpr)nctx.send.apply(new Expr[]{ node, n_0, p_0, t_0}),
+                		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),1,null,null,null,null));
+        //Constraint4		recv(n_0, node, p, t_0) -> nodeHasAddr(node,p.dest)
+        constraints.add(
+        	ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                ctx.mkImplies(
+                		(BoolExpr)nctx.recv.apply(	new Expr[]{ n_0, node, p_0, t_0}),
+    	            	(BoolExpr)nctx.nodeHasAddr.apply(new Expr[]{node, nctx.pf.get("dest").apply(p_0)})),1,null,null,null,null));
+
+//       Just a try: here we state that an endhost is not able to issue a HTTP response traffic
+//       See PolitoCache.py model for constants definition (2 means HTTP_RESPONSE, 1 means HTTP_REQUEST)
+//         constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//                 ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
+//                            ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(1))),1,null,null,null,null));
+    }
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PacketModel.java b/verigraph/service/src/mcnet/netobjs/PacketModel.java
new file mode 100644
index 0000000..5761861
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PacketModel.java
@@ -0,0 +1,70 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import com.microsoft.z3.DatatypeExpr;
+
+/*
+ * Fields that can be configured -> "dest","body","seq","proto","emailFrom","url","options"
+ */
+public class PacketModel {
+
+	private DatatypeExpr ip_dest;
+	private Integer body;
+	private Integer seq;
+	private Integer proto;
+	private Integer emailFrom;
+	private Integer url;
+	private Integer options;
+
+	public DatatypeExpr getIp_dest() {
+		return ip_dest;
+	}
+	public void setIp_dest(DatatypeExpr ip_dest) {
+		this.ip_dest = ip_dest;
+	}
+	public Integer getBody() {
+		return body;
+	}
+	public void setBody(Integer body) {
+		this.body = body;
+	}
+	public Integer getSeq() {
+		return seq;
+	}
+	public void setSeq(Integer seq) {
+		this.seq = seq;
+	}
+	public Integer getProto() {
+		return proto;
+	}
+	public void setProto(Integer proto) {
+		this.proto = proto;
+	}
+	public Integer getEmailFrom() {
+		return emailFrom;
+	}
+	public void setEmailFrom(Integer emailFrom) {
+		this.emailFrom = emailFrom;
+	}
+	public Integer getUrl() {
+		return url;
+	}
+	public void setUrl(Integer url) {
+		this.url = url;
+	}
+	public Integer getOptions() {
+		return options;
+	}
+	public void setOptions(Integer options) {
+		this.options = options;
+	}
+
+}
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoAntispam.java b/verigraph/service/src/mcnet/netobjs/PolitoAntispam.java
new file mode 100644
index 0000000..abb4615
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoAntispam.java
@@ -0,0 +1,124 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+/**
+ * Model of an anti-spam node
+ *
+ */
+public class PolitoAntispam extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoAntispam;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoAntispam(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+			isEndHost=false;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoAntispam = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        //net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoAntispam;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+				BoolExpr[] constr = new BoolExpr[constraints.size()];
+			    solver.add(constraints.toArray(constr));
+		}
+
+	    public void installAntispam (int[] blackList){
+	    	Expr n_0 = ctx.mkConst(politoAntispam+"_n_0", nctx.node);
+	    	Expr n_1 = ctx.mkConst(politoAntispam+"_n_1", nctx.node);
+	    	Expr p_0 = ctx.mkConst(politoAntispam+"_p_0", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst(politoAntispam+"_t_0");
+	    	IntExpr t_1 = ctx.mkIntConst(politoAntispam+"_t_1");
+	    	IntExpr ef_0 = ctx.mkIntConst(politoAntispam+"_ef_0");
+
+            isInBlacklist = ctx.mkFuncDecl(politoAntispam+"_isInBlacklist", ctx.mkIntSort(), ctx.mkBoolSort());
+            BoolExpr[] blConstraint = new BoolExpr[blackList.length];
+            if(blackList.length != 0){
+                for (int i=0;i<blackList.length;i++)
+                    blConstraint[i]=(ctx.mkEq(ef_0,ctx.mkInt(blackList[i])));
+                //Constraint1a		if(isInBlackList(ef_0) == or(for bl in blacklist (ef_0==bl)) ? true : false
+                constraints.add(ctx.mkForall(new Expr[]{ef_0}, ctx.mkIff((BoolExpr)isInBlacklist.apply(ef_0),ctx.mkOr(blConstraint)),1,null,null,null,null));
+            }else{
+                //Constraint1b		isInblackList(ef_0) == false
+                constraints.add(ctx.mkForall(new Expr[]{ef_0}, ctx.mkEq((BoolExpr)isInBlacklist.apply(ef_0), ctx.mkBool(false)),1,null,null,null,null));
+            }
+
+            //Constraint2		send(politoAntispam, n_0, p, t_0) && p.proto(POP3_RESP) ->
+            //						(exist  n_1,t_1 : (recv(n_1, politoAntispam, p, t_1) && t_1 < t_0)) && !isInBlackList(p.emailFrom)
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                                ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(politoAntispam, n_0, p_0, t_0), ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_RESPONSE))),
+                                    ctx.mkAnd(	ctx.mkExists(new Expr[]{n_1, t_1},
+                                              	ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1, politoAntispam, p_0, t_1), ctx.mkLt(t_1 , t_0)),1,null,null,null,null),
+                                    			ctx.mkNot((BoolExpr)isInBlacklist.apply(nctx.pf.get("emailFrom").apply(p_0))))),1,null,null,null,null));
+
+	        //Constraint3		send(politoAntispam, n_0, p, t_0) && p.proto(POP3_REQ) ->
+            //						(exist n_1,t_1 : (recv(n_1, politoAntispam, p, t_1) && t_1 < t_0))
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(politoAntispam, n_0, p_0, t_0), ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_REQUEST))),
+                        ctx.mkAnd(ctx.mkExists(new Expr[]{n_1, t_1},
+                                    ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1, politoAntispam, p_0, t_1),
+                                    			ctx.mkLt(t_1 , t_0)),1,null,null,null,null))),1,null,null,null,null));
+
+            //Constraint4		send(politoAntispam, politoErrFunction, p, t_0) ->
+            //            			(exist n_1,t_1 : (recv(n_1, politoAntispam, p, t_1) && t_1 < t_0 && p.emailFrom ==1))
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoAntispam, nctx.nm.get("politoErrFunction").getZ3Node(), p_0, t_0),
+                        ctx.mkAnd(ctx.mkExists(new Expr[]{n_1, t_1},
+                                    ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1, politoAntispam, p_0, t_1),
+                                    			ctx.mkLt(t_1 , t_0),
+                                    			ctx.mkEq(nctx.pf.get("emailFrom").apply(p_0),ctx.mkInt(1))),1,null,null,null,null))),1,null,null,null,null));
+
+	        //Constraint5		send(politoAntispam, n_0, p, t_0) -> p.proto == POP_REQ || p.protpo == POP_RESP
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoAntispam, n_0, p_0, t_0),
+                        ctx.mkOr(	ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_REQUEST)),
+                        			ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_RESPONSE)))),1,null,null,null,null));
+
+            //Constraint6		send(politoAntispam, n_0, p, t_0) -> nodeHasAddr(politoAntispam,p.src)
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoAntispam, n_0, p_0, t_0),
+                        ctx.mkNot((BoolExpr)nctx.nodeHasAddr.apply(politoAntispam,nctx.pf.get("src").apply(p_0)))),1,null,null,null,null));
+   	    }
+	}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoCache.java b/verigraph/service/src/mcnet/netobjs/PolitoCache.java
new file mode 100644
index 0000000..948915c
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoCache.java
@@ -0,0 +1,177 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Sort;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**Cache Model
+ *
+ */
+public class PolitoCache extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoCache;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoCache(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+			isEndHost=false;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoCache = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        //net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoCache;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+				BoolExpr[] constr = new BoolExpr[constraints.size()];
+			    solver.add(constraints.toArray(constr));
+		}
+
+	    public void installCache (NetworkObject[] internalNodes){
+	    	Expr n_0 = ctx.mkConst("politoCache_"+politoCache+"_n_0", nctx.node);
+	    	Expr n_1 = ctx.mkConst("politoCache_"+politoCache+"_n_1", nctx.node);
+	    	Expr n_2 = ctx.mkConst("politoCache_"+politoCache+"_n_2", nctx.node);
+	    	Expr p_0 = ctx.mkConst("politoCache_"+politoCache+"_p_0", nctx.packet);
+	    	Expr p_1 = ctx.mkConst("politoCache_"+politoCache+"_p_1", nctx.packet);
+	    	Expr p_2 = ctx.mkConst("politoCache_"+politoCache+"_p_2", nctx.packet);
+
+	    	IntExpr t_0 = ctx.mkIntConst("politoCache_"+politoCache+"_t_0");
+	    	IntExpr t_1 = ctx.mkIntConst("politoCache_"+politoCache+"_t_1");
+	    	IntExpr t_2 = ctx.mkIntConst("politoCache_"+politoCache+"_t_2");
+
+	    	Expr a_0 = ctx.mkConst(politoCache+"politoCache_a_0", nctx.node);
+	    	IntExpr u_0 = ctx.mkIntConst("politoCache_"+politoCache+"_u_0");
+
+	    	FuncDecl isInternalNode = ctx.mkFuncDecl(politoCache+"_isInternalNode", nctx.node, ctx.mkBoolSort());
+	    	FuncDecl isInCache = ctx.mkFuncDecl(politoCache+"_isInCache", new Sort[]{ctx.mkIntSort(),ctx.mkIntSort()}, ctx.mkBoolSort());
+
+	    	assert(internalNodes.length!=0); //No internal nodes => Should never happen
+
+	    	//Modeling the behavior of the isInternalNode() and isInCache() functions
+	    	BoolExpr[] internalNodesConstraint = new BoolExpr[internalNodes.length];
+	    	for(int w=0;w<internalNodesConstraint.length;w++)
+	    		internalNodesConstraint[w]= (ctx.mkEq(a_0,internalNodes[w].getZ3Node()));
+
+	    	//Constraint1		if(isInternalNode(a_0) == or(listadeinodiinterni) ? True : false
+	    	constraints.add(
+	    			 ctx.mkForall(new Expr[]{a_0},
+	    					 ctx.mkIff((BoolExpr)isInternalNode.apply(a_0), ctx.mkOr(internalNodesConstraint)),1,null,null,null,null));
+
+//	    	constraints.add(ctx.mkForall(new Expr[]{a_0}, ctx.mkEq(isInternalNode.apply(a_0),ctx.mkOr(internalNodesConstraint)),1,null,null,null,null));
+
+//	    	constraints.add(ctx.mkForall(new Expr[]{u_0, t_0},
+//                     ctx.mkITE(ctx.mkExists(new Expr[]{t_1, t_2, p_1, p_2, n_1, n_2},
+//	                        	ctx.mkAnd(ctx.mkLt(t_1, t_2),
+//	                                ctx.mkLt(t_1, t_0),
+//	                                ctx.mkLt(t_2, t_0),
+//	                                (BoolExpr)nctx.recv.apply(n_1, politoCache, p_1, t_1),
+//	                                (BoolExpr)nctx.recv.apply(n_2, politoCache, p_2, t_2),
+//	                                ctx.mkEq(nctx.pf.get("proto").apply(p_1),ctx.mkInt(nctx.HTTP_REQUEST)),
+//	                                ctx.mkEq(nctx.pf.get("proto").apply(p_2),ctx.mkInt(nctx.HTTP_RESPONSE)),
+//	                                (BoolExpr)isInternalNode.apply(n_1),
+//	                                ctx.mkNot((BoolExpr)isInternalNode.apply(n_2)),
+//	                                ctx.mkEq(nctx.pf.get("url").apply(p_1),u_0),
+//	                                ctx.mkEq(nctx.pf.get("url").apply(p_2),u_0)),1,null,null,null,null),
+//                    		 ctx.mkEq(isInCache.apply(u_0,t_0),ctx.mkBool(true)),ctx.mkEq(isInCache.apply(u_0,t_0),ctx.mkBool(false))),1,null,null,null,null));
+//
+
+	    	//Constraint2	isInCache(u_0,t_0), exist t_1, t_2, p_1, p_2, n_1, n_2 :
+	    	//						    	(   t_1< t_2 < t_0 && recv(n_1, politoCache, p_1, t_1) && recv(n_2, politoCache, p_2, t_2))) &&
+	    	//	        						p_1.proto == HTTP_REQ &&  p_2.proto == HTTP_RESP &&
+	    	//	        						isInternalNode(n_1) && !isInternalNode(n_2) &&
+	    	//	        						p_1.url == u_0 &&  p_2.url == u_0 )
+	    	constraints.add(
+	    			ctx.mkForall(new Expr[]{u_0, t_0},
+	    			 ctx.mkImplies((BoolExpr)isInCache.apply(u_0, t_0),
+	    					 ctx.mkExists(new Expr[]{t_1,t_2,p_1,p_2,n_1, n_2},
+	    							 ctx.mkAnd(
+	    									 ctx.mkLt(t_1, t_2),
+	    									 ctx.mkLt(t_1, t_0),
+	    									 ctx.mkLt(t_2, t_0),
+	    									 (BoolExpr)nctx.recv.apply(n_1, politoCache, p_1, t_1),
+	    									 (BoolExpr)nctx.recv.apply(n_2, politoCache, p_2, t_2),
+	    									 ctx.mkEq(nctx.pf.get("proto").apply(p_1), ctx.mkInt(nctx.HTTP_REQUEST)),
+	    									 ctx.mkEq(nctx.pf.get("proto").apply(p_2), ctx.mkInt(nctx.HTTP_RESPONSE)),
+	    									 (BoolExpr)isInternalNode.apply(n_1),
+	    									 ctx.mkNot((BoolExpr)isInternalNode.apply(n_2)),
+	    									 ctx.mkEq(nctx.pf.get("url").apply(p_1), u_0),
+	    									 ctx.mkEq(nctx.pf.get("url").apply(p_2), u_0)),1,null,null,null,null)),1,null,null,null,null));
+//	    	//Always in cache
+//	    	constraints.add(ctx.mkForall(new Expr[]{u_0, t_0},ctx.mkEq(isInCache.apply(u_0,t_0),ctx.mkBool(true)),1,null,null,null,null));
+
+	    	//Constraint3	Modeling the behavior of the cache
+	    	//				send(politoCache, n_0, p, t_0) && !isInternalNode(n_0) ->
+			//	    			(exist t_1,n_1 :
+			//	    		    (t_1 < t_0 && recv(n_1, politoCache, p, t_1) &&
+			//	    		     p.proto == HTTP_REQ &&  !isInCache(p.url,t_0))
+	    	constraints.add(
+	    			ctx.mkForall(new Expr[]{n_0,p_0, t_0},
+	   	    			 ctx.mkImplies(
+	   	    					 ctx.mkAnd((BoolExpr)nctx.send.apply(politoCache,n_0,p_0,t_0),ctx.mkNot((BoolExpr)isInternalNode.apply(n_0))),
+	   	    					 ctx.mkAnd(ctx.mkExists(new Expr[]{t_1, n_1},
+	   	    							 ctx.mkAnd(
+	   	    									 ctx.mkLt(t_1, t_0),
+	   	    									 (BoolExpr)isInternalNode.apply(n_1),
+	   	    									 (BoolExpr)nctx.recv.apply(n_1, politoCache, p_0, t_1)),1,null,null,null,null),
+	   	    									 ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_REQUEST)),
+	   	    									 ctx.mkNot((BoolExpr)isInCache.apply(nctx.pf.get("url").apply(p_0), t_0)))),1,null,null,null,null));
+
+	    	//Constraint4		send(politoCache, n_0, p, t_0) && isInternalNode(n_0) ->
+			//	    			(exist p_1,t_1 :
+			//	    		    	(t_1 < t_0 && recv(n_0, politoCache, p_1, t_1) &&
+			//	    		     	p_1.proto == HTTP_REQ && p.proto == HTTP_RESP &&
+			//	    		     	p_1.url == p.url &&  p.src == p_1.dest && p.dest==p_1.src
+			//	    		     	&& isInCache(p.url,t_0))
+	    	constraints.add(
+	    			ctx.mkForall(new Expr[]{n_0,p_0, t_0},
+	   	    			 ctx.mkImplies(
+	   	    					 ctx.mkAnd((BoolExpr)nctx.send.apply(politoCache,n_0,p_0,t_0),(BoolExpr)isInternalNode.apply(n_0)),
+	   	    					 ctx.mkAnd(ctx.mkExists(new Expr[]{p_1, t_1},
+	   	    							 ctx.mkAnd(
+	   	    									 ctx.mkLt(t_1, t_0),
+	   	    									(BoolExpr)nctx.recv.apply(n_0, politoCache, p_1, t_1),
+	   	    									 ctx.mkEq(nctx.pf.get("proto").apply(p_1), ctx.mkInt(nctx.HTTP_REQUEST)),
+	   	    									 ctx.mkEq(nctx.pf.get("url").apply(p_1), nctx.pf.get("url").apply(p_0))),1,null,null,null,null),
+	   	    							 ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_RESPONSE)),
+	   	    							 ctx.mkEq(nctx.pf.get("src").apply(p_0), nctx.pf.get("dest").apply(p_1)),
+	   	    							 ctx.mkEq(nctx.pf.get("dest").apply(p_0), nctx.pf.get("src").apply(p_1)),
+		    							(BoolExpr)isInCache.apply(nctx.pf.get("url").apply(p_0), t_0))),1,null,null,null,null));
+	    }
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoEndHost.java b/verigraph/service/src/mcnet/netobjs/PolitoEndHost.java
new file mode 100644
index 0000000..e12579f
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoEndHost.java
@@ -0,0 +1,100 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+public class PolitoEndHost extends NetworkObject {
+
+	List<BoolExpr> constraints = new ArrayList<BoolExpr>();
+	Context ctx;
+	DatatypeExpr politoEndHost;
+	Network net;
+	NetContext nctx;
+
+	public PolitoEndHost(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return politoEndHost;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		this.isEndHost = true;
+		this.politoEndHost = this.z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+		this.net = (Network)args[0][1];
+        this.nctx = (NetContext)args[0][2];
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		BoolExpr[] constr = new BoolExpr[constraints.size()];
+	    solver.add(constraints.toArray(constr));
+	}
+
+	/*
+	 * Fields that can be configured -> "dest","body","seq","proto","emailFrom","url","options"
+	 */
+	public void installEndHost (PacketModel packet){
+		System.out.println("Installing PolitoEndHost...");
+		Expr n_0 = ctx.mkConst("PolitoEndHost_"+politoEndHost+"_n_0", nctx.node);
+    	Expr p_0 = ctx.mkConst("PolitoEndHost_"+politoEndHost+"_p_0", nctx.packet);
+    	IntExpr t_0 = ctx.mkIntConst("PolitoEndHost_"+politoEndHost+"_t_0");
+		BoolExpr predicatesOnPktFields = ctx.mkTrue();
+
+		if(packet.getIp_dest() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("dest").apply(p_0), packet.getIp_dest()));
+		if(packet.getBody() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("body").apply(p_0), ctx.mkInt(packet.getBody())));
+		if(packet.getEmailFrom() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("emailFrom").apply(p_0), ctx.mkInt(packet.getEmailFrom())));
+		if(packet.getOptions() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("options").apply(p_0), ctx.mkInt(packet.getOptions())));
+		if(packet.getProto() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(packet.getProto())));
+		if(packet.getSeq() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("seq").apply(p_0), ctx.mkInt(packet.getSeq())));
+		if(packet.getUrl() != null)
+			predicatesOnPktFields = ctx.mkAnd(predicatesOnPktFields, ctx.mkEq(nctx.pf.get("url").apply(p_0), ctx.mkInt(packet.getUrl())));
+
+		//Constraint1		send(politoWebClient, n_0, p, t_0) -> p.origin == politoWebClient && p.orig_body == p.body && nodeHasAddr(politoWebClient,p.src)
+		constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                ctx.mkImplies((BoolExpr)nctx.send.apply(politoEndHost, n_0, p_0, t_0),
+                		ctx.mkAnd(predicatesOnPktFields,
+                				  ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0)),
+                				  ctx.mkEq(nctx.pf.get("origin").apply(p_0),politoEndHost),
+                				  (BoolExpr)nctx.nodeHasAddr.apply(politoEndHost,nctx.pf.get("src").apply(p_0)))),1,null,null,null,null));
+
+		//Constraint2		recv(n_0, politoWebClient, p, t_0) -> nodeHasAddr(politoWebClient,p.dest)
+		constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,politoEndHost, p_0, t_0),
+                		(BoolExpr)nctx.nodeHasAddr.apply(politoEndHost,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+		System.out.println("Done.");
+		return;
+	}
+
+}
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoErrFunction.java b/verigraph/service/src/mcnet/netobjs/PolitoErrFunction.java
new file mode 100644
index 0000000..5f84b9f
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoErrFunction.java
@@ -0,0 +1,96 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**Error Function objects
+ *
+ */
+public class PolitoErrFunction extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoErrFunction;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoErrFunction(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+			isEndHost=true;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoErrFunction = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        errFunctionRules();
+	        //net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoErrFunction;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+//			System.out.println("[ERR FUNC] Installing rules.");
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+			solver.add(constraints.toArray(constr));
+		}
+
+	    private void errFunctionRules (){
+	    	Expr n_0 = ctx.mkConst("PolitoErrFunction_"+politoErrFunction+"_n_0", nctx.node);
+	    	Expr p_0 = ctx.mkConst("PolitoErrFunction_"+politoErrFunction+"_p_0", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst("PolitoErrFunction_"+politoErrFunction+"_t_0");
+
+//	    	 constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//	    			 ctx.mkImplies((BoolExpr)nctx.send.apply(politoErrFunction, n_0, p_0, t_0),
+//	                 (BoolExpr)nctx.nodeHasAddr.apply(politoErrFunction, nctx.pf.get("src").apply(p_0))),1,null,null,null,null));
+//	    	 constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//	    			 ctx.mkImplies((BoolExpr)nctx.send.apply(politoErrFunction, n_0, p_0, t_0),
+//	                 ctx.mkEq(nctx.pf.get("origin").apply(p_0), politoErrFunction)),1,null,null,null,null));
+//
+//	    	 constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//	    			 ctx.mkImplies((BoolExpr)nctx.send.apply(politoErrFunction, n_0, p_0, t_0),
+//	    		                ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),1,null,null,null,null));
+
+
+//            Constraint1  	We want the ErrFunction not to send out any packet
+//	    					send(politoErrFunction, n_0, p, t_0) -> 1 == 2
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoErrFunction, n_0, p_0, t_0),
+                        			ctx.mkEq(ctx.mkInt(1),ctx.mkInt(2))),1,null,null,null,null));
+
+//            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//            		ctx.mkImplies(	(BoolExpr)nctx.send.apply(n_0, politoErrFunction, p_0, t_0),
+//                            		(BoolExpr)nctx.nodeHasAddr.apply(politoErrFunction, nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+	    }
+	}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoFieldModifier.java b/verigraph/service/src/mcnet/netobjs/PolitoFieldModifier.java
new file mode 100644
index 0000000..6d8d8fe
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoFieldModifier.java
@@ -0,0 +1,91 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+public class PolitoFieldModifier extends NetworkObject {
+
+	List<BoolExpr> constraints;
+	Context ctx;
+	DatatypeExpr politoFieldModifier;
+	Network net;
+	NetContext nctx;
+
+	public PolitoFieldModifier(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return politoFieldModifier;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		isEndHost=false;
+   		constraints = new ArrayList<BoolExpr>();
+        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+        politoFieldModifier = z3Node;
+        net = (Network)args[0][1];
+        nctx = (NetContext)args[0][2];
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		BoolExpr[] constr = new BoolExpr[constraints.size()];
+	    solver.add(constraints.toArray(constr));
+	}
+
+	public void installFieldModifier (){
+		Expr x = ctx.mkConst("politoFieldModifier_"+politoFieldModifier+"_x", nctx.node);
+    	Expr y = ctx.mkConst("politoFieldModifier_"+politoFieldModifier+"_y", nctx.node);
+    	Expr p_0 = ctx.mkConst("politoFieldModifier_"+politoFieldModifier+"_p_0", nctx.packet);
+    	Expr p_1 = ctx.mkConst("politoFieldModifier_"+politoFieldModifier+"_p_1", nctx.packet);
+
+    	IntExpr t_0 = ctx.mkIntConst("politoFieldModifier_"+politoFieldModifier+"_t_0");
+    	IntExpr t_1 = ctx.mkIntConst("politoFieldModifier_"+politoFieldModifier+"_t_1");
+
+    	constraints.add(
+    			ctx.mkForall(new Expr[]{t_0, p_0, x},
+    				ctx.mkImplies((BoolExpr)nctx.send.apply(politoFieldModifier,x,p_0,t_0),
+    							  ctx.mkExists(new Expr[]{y, p_1, t_1},
+  	    							 ctx.mkAnd(ctx.mkLt(t_1, t_0),
+  	    									   (BoolExpr)nctx.recv.apply(y, politoFieldModifier, p_1, t_1),
+  	    									   ctx.mkEq(nctx.pf.get("encrypted").apply(p_0), nctx.pf.get("encrypted").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("src").apply(p_0), nctx.pf.get("src").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("dest").apply(p_0), nctx.pf.get("dest").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("inner_src").apply(p_0), nctx.pf.get("inner_src").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("inner_dest").apply(p_0), nctx.pf.get("inner_dest").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("origin").apply(p_0), nctx.pf.get("origin").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("orig_body").apply(p_0), nctx.pf.get("orig_body").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("body").apply(p_0), nctx.pf.get("body").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("seq").apply(p_0), nctx.pf.get("seq").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("proto").apply(p_0), nctx.pf.get("proto").apply(p_1)),
+  	    									   ctx.mkEq(nctx.pf.get("emailFrom").apply(p_0), nctx.pf.get("emailFrom").apply(p_1)),
+  	    									   ctx.mkNot(ctx.mkEq(nctx.pf.get("url").apply(p_0), nctx.pf.get("url").apply(p_1))),
+  	    									   ctx.mkEq(nctx.pf.get("options").apply(p_0), nctx.pf.get("options").apply(p_1))),1,null,null,null,null)),
+    			1,null,null,null,null));
+	}
+
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoIDS.java b/verigraph/service/src/mcnet/netobjs/PolitoIDS.java
new file mode 100644
index 0000000..6f2cddf
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoIDS.java
@@ -0,0 +1,140 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+public class PolitoIDS extends NetworkObject {
+
+	public static final int DROGA = 1; //no go
+	public static final int GATTINI = 2;  //go
+
+	Context ctx;
+	List<BoolExpr> constraints = new ArrayList<BoolExpr>();
+	DatatypeExpr politoIDS;
+	Network net;
+	NetContext nctx;
+	FuncDecl isInBlacklist;
+
+
+	public PolitoIDS(Context ctx, Object[]...args){
+		super(ctx, args);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return politoIDS;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+
+		this.ctx = ctx;
+		this.isEndHost = false;
+		this.politoIDS = this.z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+		this.net = (Network)args[0][1];
+        this.nctx = (NetContext)args[0][2];
+
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		BoolExpr[] constr = new BoolExpr[constraints.size()];
+	    solver.add(constraints.toArray(constr));
+
+	}
+
+	public void installIDS(int[] blackList){
+		Expr n_0 = ctx.mkConst(politoIDS + "_n_0", nctx.node);
+		Expr n_1 = ctx.mkConst(politoIDS + "_n_1", nctx.node);
+		Expr p_0 = ctx.mkConst(politoIDS + "_p_0", nctx.packet);
+		IntExpr t_0 = ctx.mkIntConst(politoIDS + "_t_0");
+		IntExpr t_1 = ctx.mkIntConst(politoIDS + "_t_1");
+		Expr b_0 = ctx.mkIntConst(politoIDS + "_b_0");
+
+		isInBlacklist = ctx.mkFuncDecl(politoIDS + "_isInBlacklist", ctx.mkIntSort(), ctx.mkBoolSort());
+
+
+		BoolExpr[] blConstraints = new BoolExpr[blackList.length];
+		if(blackList.length != 0){
+
+			for(int i = 0; i<blackList.length; i++)
+				blConstraints[i] = ctx.mkEq(b_0, ctx.mkInt(blackList[i]));
+
+			this.constraints.add(ctx.mkForall(new Expr[]{b_0},
+											  ctx.mkIff((BoolExpr)isInBlacklist.apply(b_0), ctx.mkOr(blConstraints)),
+											  1,
+											  null, null, null, null));
+		}else{
+			this.constraints.add(ctx.mkForall(new Expr[]{b_0},
+											  ctx.mkEq(isInBlacklist.apply(b_0), ctx.mkBool(false)),
+											  1,
+											  null, null, null, null));
+		}
+
+		//Constraint2    		send(politoIDS, n_0, p, t_0) && (p.proto(HTTP_RESPONSE) || p.proto(HTTP_REQUEST)) ->
+        //						(exist  n_1,t_1 : (recv(n_1, politoIDS, p, t_1) && t_1 < t_0)) && !isInBlackList(p.body)
+
+		this.constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+										  ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(politoIDS, n_0, p_0, t_0), ctx.mkOr(ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_RESPONSE)), ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_REQUEST)))),
+												  		ctx.mkAnd(ctx.mkExists(new Expr[]{n_1,t_1},
+												  							   ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1,politoIDS,p_0,t_1),ctx.mkLt(t_1, t_0)),
+												  							   1,
+												  							   null, null, null, null),
+												  				  ctx.mkNot((BoolExpr)isInBlacklist.apply(nctx.pf.get("body").apply(p_0))))),
+										  1,
+										  null, null, null, null));
+
+		//Constraint3		send(politoIDS, n_0, p, t_0) && p.proto(HTTP_REQUEST) ->
+        //						(exist n_1,t_1 : (recv(n_1, politoIDS, p, t_1) && t_1 < t_0)) Constraint not needed anymore (included in contr. 2)
+		/*
+		this.constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+										  ctx.mkImplies(ctx.mkAnd((BoolExpr)nctx.send.apply(politoIDS, n_0, p_0, t_0), ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_REQUEST))),
+												  		ctx.mkAnd(ctx.mkExists(new Expr[]{n_1,t_1},
+												  							   ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1,politoIDS,p_0,t_1),ctx.mkLt(t_1, t_0)),
+												  							   1,
+												  							   null, null, null, null))),
+										  1,
+										  null, null, null, null));
+		*/
+
+		//Constraint5		send(politoIDS, n_0, p, t_0) -> p.proto == HTTP_REQ || p.protpo == HTTP_RESP
+
+        this.constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                						  ctx.mkImplies((BoolExpr)nctx.send.apply(politoIDS, n_0, p_0, t_0),
+                								  		ctx.mkOr(ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_REQUEST)),
+                								  				 ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_RESPONSE)))),
+                						  1,
+                						  null,null,null,null));
+
+        //Constraint6		send(politoIDS, n_0, p, t_0) -> nodeHasAddr(politoIDS,p.src)
+
+        this.constraints.add(ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                						  ctx.mkImplies((BoolExpr)nctx.send.apply(politoIDS, n_0, p_0, t_0),
+                								  		ctx.mkNot((BoolExpr)nctx.nodeHasAddr.apply(politoIDS,nctx.pf.get("src").apply(p_0)))),
+                						  1,
+                						  null,null,null,null));
+
+	}
+
+}
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoMailClient.java b/verigraph/service/src/mcnet/netobjs/PolitoMailClient.java
new file mode 100644
index 0000000..6925258
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoMailClient.java
@@ -0,0 +1,106 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**
+ *  MailClient objects
+ *
+ */
+public class PolitoMailClient extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoMailClient;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoMailClient(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+	        isEndHost=true;
+		   	constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoMailClient = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        DatatypeExpr ipServer = (DatatypeExpr) args[0][3];
+	        mailClientRules(ipServer);
+	        //net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoMailClient;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+//			System.out.println("[MailClient] Installing rules.");
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+			solver.add(constraints.toArray(constr));
+		}
+
+	    private void mailClientRules (DatatypeExpr ipServer){
+	    	Expr n_0 = ctx.mkConst("PolitoMailClient_"+politoMailClient+"_n_0", nctx.node);
+	    	Expr p_0 = ctx.mkConst("PolitoMailClient_"+politoMailClient+"_p_0", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst("PolitoMailClient_"+politoMailClient+"_t_0");
+
+//            Constraint1		send(politoMailClient, n_0, p, t_0) -> nodeHasAddr(politoMailClient,p.src)
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailClient, n_0, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoMailClient,nctx.pf.get("src").apply(p_0))),1,null,null,null,null));
+
+//            Constraint2		send(politoMailClient, n_0, p, t_0) -> p.origin == politoMailClient
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailClient, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("origin").apply(p_0),politoMailClient)),1,null,null,null,null));
+
+//            Constraint3		send(politoMailClient, n_0, p, t_0) -> p.orig_body == p.body
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailClient, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),1,null,null,null,null));
+
+//            Constraint4		recv(n_0, politoMailClient, p, t_0) -> nodeHasAddr(politoMailClient,p.dest)
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,politoMailClient, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoMailClient,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+//            Constraint5		This client is only able to produce POP3 requests
+//								send(politoMailClient, n_0, p, t_0) -> p.proto == POP3_REQ
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailClient, n_0, p_0, t_0),
+                        ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_REQUEST))),1,null,null,null,null));
+
+//            Constraint6		send(politoMailClient, n_0, p, t_0) -> p.dest == ip_mailServer
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailClient, n_0, p_0, t_0),
+                            ctx.mkEq(nctx.pf.get("dest").apply(p_0), ipServer)),1,null,null,null,null));
+		}
+}
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoMailServer.java b/verigraph/service/src/mcnet/netobjs/PolitoMailServer.java
new file mode 100644
index 0000000..c464195
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoMailServer.java
@@ -0,0 +1,117 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/** Mail server objects
+ *
+ */
+public class PolitoMailServer extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoMailServer;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoMailServer(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+			isEndHost=false;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoMailServer = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        mailServerRules();
+	        net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoMailServer;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+				BoolExpr[] constr = new BoolExpr[constraints.size()];
+			    solver.add(constraints.toArray(constr));
+		}
+
+	    private void mailServerRules (){
+	    	Expr n_0 = ctx.mkConst(politoMailServer+"_n_0", nctx.node);
+	    	Expr p_0 = ctx.mkConst(politoMailServer+"_p_0", nctx.packet);
+	    	Expr p_1 = ctx.mkConst(politoMailServer+"_p_1", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst(politoMailServer+"_t_0");
+	    	IntExpr t_1 = ctx.mkIntConst(politoMailServer+"_t_1");
+
+//            Constraint1		send(politoMailServer, n_0, p, t_0) -> nodeHasAddr(politoMailServer,p.src)
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoMailServer,nctx.pf.get("src").apply(p_0))),1,null,null,null,null));
+
+//            Constraint2		send(politoMailServer, n_0, p, t_0) -> p.origin == politoMailServer
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("origin").apply(p_0),politoMailServer)),1,null,null,null,null));
+
+//            Constraint3		send(politoMailServer, n_0, p, t_0) -> p.orig_body == p.body
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),1,null,null,null,null));
+
+//            Constraint4		recv(n_0, politoMailServer, p, t_0) -> nodeHasAddr(politoMailServer,p.dest)
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,politoMailServer, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoMailServer,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+//            Constraint5		send(politoMailServer, n_0, p, t_0) -> p.proto == POP3_RESP && p.emailFrom == 1
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+                       ctx.mkAnd(	ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_RESPONSE)),
+                    		   		ctx.mkEq(nctx.pf.get("emailFrom").apply(p_0), ctx.mkInt(1)))),1,null,null,null,null));
+
+//            Constraint6		send(politoMailServer, n_0, p, t_0)  ->
+//					    		(exist p_1, t_1 : (t_1 < t_0 && recv(n_0, politoMailServer, p_1, t_1) &&
+//	    						p_0.proto == POP3_RESP &&  p_1.proto == POP3_REQ && p_0.dest == p_1.src )
+
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+                        ctx.mkExists(new Expr[]{p_1, t_1},
+                            ctx.mkAnd(ctx.mkLt(t_1, t_0),
+                            		(BoolExpr)nctx.recv.apply(n_0, politoMailServer, p_1, t_1),
+                            		ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.POP3_RESPONSE)),
+                            		ctx.mkEq(nctx.pf.get("proto").apply(p_1), ctx.mkInt(nctx.POP3_REQUEST)),
+                            		ctx.mkEq(nctx.pf.get("dest").apply(p_0), nctx.pf.get("src").apply(p_1))),1,null,null,null,null)),1,null,null,null,null));
+
+//	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+//                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoMailServer, n_0, p_0, t_0),
+//                    		ctx.mkEq(nctx.pf.get("emailFrom").apply(p_0),ctx.mkInt(2))),1,null,null,null,null));
+	    }
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoNF.java b/verigraph/service/src/mcnet/netobjs/PolitoNF.java
new file mode 100644
index 0000000..53cae28
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoNF.java
@@ -0,0 +1,101 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+import com.microsoft.z3.Sort;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+/** First example of custom network function: a simple filter
+ *
+ */
+public class PolitoNF extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoNF;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+
+		public PolitoNF(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+			isEndHost=false;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        politoNF = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        //net.saneSend(this);
+	    }
+
+	    public void politoNFRules (DatatypeExpr ipA,DatatypeExpr ipB){
+//	    	System.out.println("[PolitoNf] Installing rules");
+	    	Expr n_0 = ctx.mkConst("politoNF_"+politoNF+"_n_0", nctx.node);
+	    	Expr n_1 = ctx.mkConst("politoNF_"+politoNF+"_n_1", nctx.node);
+	    	Expr p_0 = ctx.mkConst("politoNF_"+politoNF+"_p_0", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst("politoNF_"+politoNF+"_t_0");
+	    	IntExpr t_1 = ctx.mkIntConst("politoNF_"+politoNF+"_t_1");
+	    	Expr a_0 = ctx.mkConst(politoNF+"_politoNF_a_0", nctx.address);
+	    	Expr a_1 = ctx.mkConst(politoNF+"_politoNF_a_1", nctx.address);
+
+	    	FuncDecl myFunction = ctx.mkFuncDecl(politoNF+"_myFunction", new Sort[]{nctx.address,nctx.address}, ctx.mkBoolSort());
+
+	    	BoolExpr myConstraint = ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+	    			 ctx.mkImplies((BoolExpr)nctx.send.apply(politoNF, n_0, p_0, t_0),
+	    					 ctx.mkExists(new Expr[]{n_1, t_1},
+	    							 ctx.mkAnd((BoolExpr)nctx.recv.apply(n_1, politoNF, p_0, t_1),
+	    									 	ctx.mkLt(t_1 , t_0),
+	    									 	(BoolExpr)myFunction.apply(nctx.pf.get("src").apply(p_0), nctx.pf.get("dest").apply(p_0))),1,null,null,null,null)),1,null,null,null,null);
+
+	    	BoolExpr funcConstraint = ctx.mkOr(ctx.mkAnd(ctx.mkEq(a_0, ipA), ctx.mkEq(a_1, ipB)), ctx.mkAnd(ctx.mkEq(a_0,ipB), ctx.mkEq(a_1,ipA)));
+
+	    	// Constraint1		myFunction(a_0,a_1) == ((a_0 == ipA && a_1 == ipB) || (a_0 == ipB && a_1 == ipA))
+			 constraints.add(
+					 ctx.mkForall(new Expr[]{a_0,a_1},
+							 ctx.mkEq(myFunction.apply(a_0, a_1), funcConstraint),1,null,null,null,null));
+
+			//Constraint2		send(politoNF, n_0, p, t_0)  ->
+			 //					(exist n_1,t_1 : (t_1 < t_0 && recv(n_1, politoNF, p, t_1) && myFunction(p.src,p.dest))
+			 constraints.add(myConstraint);
+
+	    }
+
+	    @Override
+		protected void addConstraints(Solver solver) {
+				BoolExpr[] constr = new BoolExpr[constraints.size()];
+			    solver.add(constraints.toArray(constr));
+		}
+
+	    @Override
+		public DatatypeExpr getZ3Node() {
+			return politoNF;
+		}
+
+	}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoNat.java b/verigraph/service/src/mcnet/netobjs/PolitoNat.java
new file mode 100644
index 0000000..6d8a36d
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoNat.java
@@ -0,0 +1,176 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**
+ * NAT Model object
+ *
+ */
+public class PolitoNat extends NetworkObject{
+	List<BoolExpr> constraints;
+	Context ctx;
+	DatatypeExpr nat;
+	List<DatatypeExpr> private_addresses;
+	List<NetworkObject> private_node;
+	Network net;
+	NetContext nctx;
+	FuncDecl private_addr_func ;
+
+	public PolitoNat(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		isEndHost=false;
+   		constraints = new ArrayList<BoolExpr>();
+        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+        nat = z3Node;
+        net = (Network)args[0][1];
+        nctx = (NetContext)args[0][2];
+        private_addresses = new ArrayList<DatatypeExpr>();
+        private_node = new ArrayList<NetworkObject>();
+        net.saneSend(this);
+    }
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return nat;
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+		    solver.add(constraints.toArray(constr));
+	}
+
+	/*
+	private void addPrivateAdd(List<DatatypeExpr> address){
+		private_addresses.addAll(address);
+	}
+	*/
+
+	public List<DatatypeExpr> getPrivateAddress(){
+		return private_addresses;
+	}
+
+    public void natModel(DatatypeExpr natIp){
+    	Expr x = ctx.mkConst("x", nctx.node);
+    	Expr y = ctx.mkConst("y", nctx.node);
+    	Expr z = ctx.mkConst("z", nctx.node);
+
+    	Expr p_0 = ctx.mkConst("p_0", nctx.packet);
+    	Expr p_1 = ctx.mkConst("p_1", nctx.packet);
+    	Expr p_2 = ctx.mkConst("p_2", nctx.packet);
+
+    	IntExpr t_0 = ctx.mkIntConst("t_0");
+    	IntExpr t_1 = ctx.mkIntConst("t_1");
+    	IntExpr t_2 = ctx.mkIntConst("t_2");
+
+//    	private_addr_func = ctx.mkFuncDecl("private_addr_func", nctx.address, ctx.mkBoolSort());
+    	private_addr_func = ctx.mkFuncDecl(nat + "_nat_func", nctx.address, ctx.mkBoolSort());
+
+    	//Constraint1
+//    	"send(nat, x, p_0, t_0) && !private_addr_func(p_0.dest) ->
+//    	p_0.src == ip_politoNat &&
+//    	(exist y, p_1,t_1 :
+//    	   (recv(y, nat, p_1, t_1) && t_1 < t_0 &&
+//    	    private_addr_func(p1.src) &&
+//    	    p_1.origin == p_0.origin &&
+//    	    same for p_1.<dest,orig_body,body,seq,proto,emailFrom,url,options> == p_0.<...>) "
+    	constraints.add( ctx.mkForall(new Expr[]{t_0, p_0, x},
+    		ctx.mkImplies(
+    				ctx.mkAnd((BoolExpr)nctx.send.apply(nat, x, p_0, t_0),
+    						ctx.mkNot((BoolExpr)private_addr_func.apply(nctx.pf.get("dest").apply(p_0)))),
+    				ctx.mkAnd(
+    						ctx.mkEq(nctx.pf.get("src").apply(p_0),natIp),
+    						ctx.mkExists(new Expr[]{y, p_1, t_1},
+    								ctx.mkAnd(
+    									(BoolExpr)nctx.recv.apply(y, nat, p_1, t_1),
+    									ctx.mkLt(t_1 , t_0),
+    									(BoolExpr)private_addr_func.apply(nctx.pf.get("src").apply(p_1)),
+    									ctx.mkEq(nctx.pf.get("origin").apply(p_1),nctx.pf.get("origin").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("dest").apply(p_1),nctx.pf.get("dest").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("orig_body").apply(p_1),nctx.pf.get("orig_body").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("body").apply(p_1),nctx.pf.get("body").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("seq").apply(p_1),nctx.pf.get("seq").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("proto").apply(p_1),nctx.pf.get("proto").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1),nctx.pf.get("emailFrom").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("url").apply(p_1),nctx.pf.get("url").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("options").apply(p_1),nctx.pf.get("options").apply(p_0))),1,null,null,null,null))),1,null,null,null,null));
+
+    	//Constraint2
+//    	send(nat, x, p_0, t_0) && private_addr_func(p_0.dest) ->
+//    	!private_addr_func(p_0.src) &&
+//    	(exist y, p_1,t_1 :
+//    	  (recv(y, nat, p_1, t_1) && t_1 < t_0 &&
+//    	   !private_addr_func(p1.src) &&
+//    	   p_1.dest == ip_politoNat &&
+//    	   p_1.origin == p_0.origin &&
+//    	   same for p_1.<src,orig_body,body,seq,proto,emailFrom,url,options> == p_0.<...>)
+    	constraints.add( ctx.mkForall(new Expr[]{x, p_0, t_0},
+    			ctx.mkImplies(
+    				ctx.mkAnd((BoolExpr)nctx.send.apply(nat, x, p_0, t_0),
+    					(BoolExpr)private_addr_func.apply(nctx.pf.get("dest").apply(p_0))),
+    					ctx.mkAnd(
+    						ctx.mkNot((BoolExpr)private_addr_func.apply(nctx.pf.get("src").apply(p_0))),
+    						ctx.mkExists(new Expr[]{y, p_1, t_1},
+    							ctx.mkAnd(
+    									ctx.mkLt(t_1 , t_0),
+    									(BoolExpr)nctx.recv.apply(y, nat, p_1, t_1),
+    									ctx.mkNot((BoolExpr)private_addr_func.apply(nctx.pf.get("src").apply(p_1))),
+    									ctx.mkEq(nctx.pf.get("dest").apply(p_1),natIp),
+    									ctx.mkEq(nctx.pf.get("src").apply(p_1),nctx.pf.get("src").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("origin").apply(p_0),nctx.pf.get("origin").apply(p_1)),
+    									ctx.mkEq(nctx.pf.get("orig_body").apply(p_1),nctx.pf.get("orig_body").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("body").apply(p_1),nctx.pf.get("body").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("seq").apply(p_1),nctx.pf.get("seq").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("proto").apply(p_1),nctx.pf.get("proto").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1),nctx.pf.get("emailFrom").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("url").apply(p_1),nctx.pf.get("url").apply(p_0)),
+    									ctx.mkEq(nctx.pf.get("options").apply(p_1),nctx.pf.get("options").apply(p_0)),
+    									ctx.mkExists(new Expr[]{z, p_2, t_2},
+    										ctx.mkAnd(
+    												ctx.mkLt(t_2 , t_1),
+    												(BoolExpr)nctx.recv.apply(z, nat, p_2, t_2),
+    												(BoolExpr)private_addr_func.apply(nctx.pf.get("src").apply(p_2)),
+    												ctx.mkEq(nctx.pf.get("src").apply(p_1),nctx.pf.get("dest").apply(p_2)),
+    												ctx.mkEq(nctx.pf.get("src").apply(p_0),nctx.pf.get("dest").apply(p_2)),
+    												ctx.mkEq(nctx.pf.get("src").apply(p_2),nctx.pf.get("dest").apply(p_0))),1,null,null,null,null)),1,null,null,null,null))),1,null,null,null,null));
+    }
+
+    public void setInternalAddress(ArrayList<DatatypeExpr> internalAddress){
+    	List<BoolExpr> constr = new ArrayList<BoolExpr>();
+    	Expr n_0 = ctx.mkConst("nat_node", nctx.address);
+
+    	for(DatatypeExpr n : internalAddress){
+    		constr.add(ctx.mkEq(n_0,n));
+    	}
+    	BoolExpr[] constrs = new BoolExpr[constr.size()];
+    	//Constraint		private_addr_func(n_0) == or(n_0==n foreach internal address)
+    	constraints.add(ctx.mkForall(new Expr[]{n_0}, ctx.mkEq(private_addr_func.apply(n_0),ctx.mkOr(constr.toArray(constrs))),1,null,null,null,null));
+    }
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoVpnAccess.java b/verigraph/service/src/mcnet/netobjs/PolitoVpnAccess.java
new file mode 100644
index 0000000..e6fc5fe
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoVpnAccess.java
@@ -0,0 +1,142 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+public class PolitoVpnAccess extends NetworkObject {
+
+	List<BoolExpr> constraints = new ArrayList<BoolExpr>();
+	DatatypeExpr politoVpnAccess;
+	FuncDecl private_addr_func;
+	NetContext nctx;
+	Context ctx;
+	Network net;
+
+	public PolitoVpnAccess(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return politoVpnAccess;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		this.isEndHost = false;
+		this.politoVpnAccess = this.z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+		this.net = (Network)args[0][1];
+        this.nctx = (NetContext)args[0][2];
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		BoolExpr[] constr = new BoolExpr[constraints.size()];
+	    solver.add(constraints.toArray(constr));
+	}
+
+	public void vpnAccessModel(DatatypeExpr vpnAccessIp, DatatypeExpr vpnExitIp) {
+		Expr x = ctx.mkConst("vpn_x", nctx.node);
+		Expr y = ctx.mkConst("vpn_y", nctx.node);
+
+		Expr p_0 = ctx.mkConst("vpn_p_0", nctx.packet);
+		Expr p_1 = ctx.mkConst("vpn_p_1", nctx.packet);
+
+		IntExpr t_0 = ctx.mkIntConst("vpn_t_0");
+		IntExpr t_1 = ctx.mkIntConst("vpn_t_1");
+
+		private_addr_func = ctx.mkFuncDecl("vpn_private_addr_func", nctx.address, ctx.mkBoolSort());
+
+		BoolExpr constraint1 = ctx.mkForall(new Expr[]{t_0, p_0, x},
+				ctx.mkImplies(ctx.mkAnd(
+									  (BoolExpr)nctx.send.apply(politoVpnAccess, x, p_0, t_0),
+									  ctx.mkEq(nctx.pf.get("inner_src").apply(p_0), nctx.am.get("null"))),
+							  ctx.mkAnd(
+									  (BoolExpr)private_addr_func.apply(nctx.pf.get("dest").apply(p_0)),
+									  ctx.mkNot((BoolExpr)nctx.pf.get("encrypted").apply(p_0)),
+									  ctx.mkExists(new Expr[]{y, p_1, t_1},
+											  ctx.mkAnd((BoolExpr)nctx.recv.apply(y, politoVpnAccess, p_1, t_1),
+													    ctx.mkLt(t_1, t_0),
+													    (BoolExpr)nctx.pf.get("encrypted").apply(p_1),
+													    ctx.mkEq(nctx.pf.get("src").apply(p_1), vpnExitIp),
+													    ctx.mkEq(nctx.pf.get("dest").apply(p_1), vpnAccessIp),
+													    ctx.mkEq(nctx.pf.get("inner_src").apply(p_1), nctx.pf.get("src").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("inner_dest").apply(p_1), nctx.pf.get("dest").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("origin").apply(p_1), nctx.pf.get("origin").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("orig_body").apply(p_1), nctx.pf.get("orig_body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("body").apply(p_1), nctx.pf.get("body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("seq").apply(p_1), nctx.pf.get("seq").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("proto").apply(p_1), nctx.pf.get("proto").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1), nctx.pf.get("emailFrom").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("url").apply(p_1), nctx.pf.get("url").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("options").apply(p_1), nctx.pf.get("options").apply(p_0))), 1, null, null, null, null))),
+			1,null,null,null,null);
+
+		constraints.add(constraint1);
+
+		BoolExpr constraint2 = ctx.mkForall(new Expr[]{t_0, p_0, x},
+				ctx.mkImplies(ctx.mkAnd(
+									  (BoolExpr)nctx.send.apply(politoVpnAccess, x, p_0, t_0),
+									  ctx.mkNot(ctx.mkEq(nctx.pf.get("inner_src").apply(p_0), nctx.am.get("null")))),
+							  ctx.mkAnd(
+									  ctx.mkEq(nctx.pf.get("src").apply(p_0), vpnAccessIp),
+									  ctx.mkEq(nctx.pf.get("dest").apply(p_0), vpnExitIp),
+									  (BoolExpr)private_addr_func.apply(nctx.pf.get("inner_src").apply(p_0)),
+									  ctx.mkNot(ctx.mkEq(nctx.pf.get("inner_dest").apply(p_0), vpnAccessIp)),
+									  (BoolExpr)nctx.pf.get("encrypted").apply(p_0),
+									  ctx.mkExists(new Expr[]{y, p_1, t_1},
+											  ctx.mkAnd((BoolExpr)nctx.recv.apply(y, politoVpnAccess, p_1, t_1),
+													    ctx.mkLt(t_1, t_0),
+													    ctx.mkNot((BoolExpr)nctx.pf.get("encrypted").apply(p_1)),
+													    ctx.mkEq(nctx.pf.get("src").apply(p_1), nctx.pf.get("inner_src").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("dest").apply(p_1), nctx.pf.get("inner_dest").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("inner_src").apply(p_1), nctx.am.get("null")),
+													    ctx.mkEq(nctx.pf.get("inner_dest").apply(p_1), nctx.am.get("null")),
+													    ctx.mkEq(nctx.pf.get("origin").apply(p_1), nctx.pf.get("origin").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("orig_body").apply(p_1), nctx.pf.get("orig_body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("body").apply(p_1), nctx.pf.get("body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("seq").apply(p_1), nctx.pf.get("seq").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("proto").apply(p_1), nctx.pf.get("proto").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1), nctx.pf.get("emailFrom").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("url").apply(p_1), nctx.pf.get("url").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("options").apply(p_1), nctx.pf.get("options").apply(p_0))), 1, null, null, null, null))),
+				1,null,null,null,null);
+
+		constraints.add(constraint2);
+	}
+
+	public void setInternalAddress(ArrayList<DatatypeExpr> internalAddress){
+    	List<BoolExpr> constr = new ArrayList<BoolExpr>();
+    	Expr n_0 = ctx.mkConst("vpn_node", nctx.address);
+
+    	for(DatatypeExpr n : internalAddress){
+    		constr.add(ctx.mkEq(n_0,n));
+    	}
+    	BoolExpr[] constrs = new BoolExpr[constr.size()];
+    	//Constraint		private_addr_func(n_0) == or(n_0==n foreach internal address)
+    	constraints.add(ctx.mkForall(new Expr[]{n_0}, ctx.mkEq(private_addr_func.apply(n_0),ctx.mkOr(constr.toArray(constrs))),1,null,null,null,null));
+    }
+
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoVpnExit.java b/verigraph/service/src/mcnet/netobjs/PolitoVpnExit.java
new file mode 100644
index 0000000..fb2341f
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoVpnExit.java
@@ -0,0 +1,142 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+public class PolitoVpnExit extends NetworkObject {
+
+	List<BoolExpr> constraints = new ArrayList<BoolExpr>();
+	DatatypeExpr politoVpnExit;
+	FuncDecl private_addr_func;
+	NetContext nctx;
+	Context ctx;
+	Network net;
+
+	public PolitoVpnExit(Context ctx, Object[]... args) {
+		super(ctx, args);
+	}
+
+	@Override
+	public DatatypeExpr getZ3Node() {
+		return politoVpnExit;
+	}
+
+	@Override
+	protected void init(Context ctx, Object[]... args) {
+		this.ctx = ctx;
+		this.isEndHost = false;
+		this.politoVpnExit = this.z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+		this.net = (Network)args[0][1];
+        this.nctx = (NetContext)args[0][2];
+	}
+
+	@Override
+	protected void addConstraints(Solver solver) {
+		BoolExpr[] constr = new BoolExpr[constraints.size()];
+	    solver.add(constraints.toArray(constr));
+	}
+
+	public void vpnAccessModel(DatatypeExpr vpnAccessIp, DatatypeExpr vpnExitIp) {
+		Expr x = ctx.mkConst("vpn_x", nctx.node);
+		Expr y = ctx.mkConst("vpn_y", nctx.node);
+
+		Expr p_0 = ctx.mkConst("vpn_p_0", nctx.packet);
+		Expr p_1 = ctx.mkConst("vpn_p_1", nctx.packet);
+
+		IntExpr t_0 = ctx.mkIntConst("vpn_t_0");
+		IntExpr t_1 = ctx.mkIntConst("vpn_t_1");
+
+		private_addr_func = ctx.mkFuncDecl("vpn_private_addr_func", nctx.address, ctx.mkBoolSort());
+
+		BoolExpr constraint1 = ctx.mkForall(new Expr[]{t_0, p_0, x},
+				ctx.mkImplies(ctx.mkAnd(
+									  (BoolExpr)nctx.send.apply(politoVpnExit, x, p_0, t_0),
+									  ctx.mkEq(nctx.pf.get("inner_src").apply(p_0), nctx.am.get("null"))),
+							  ctx.mkAnd(
+									  (BoolExpr)private_addr_func.apply(nctx.pf.get("src").apply(p_0)),
+									  ctx.mkNot((BoolExpr)nctx.pf.get("encrypted").apply(p_0)),
+									  ctx.mkExists(new Expr[]{y, p_1, t_1},
+											  ctx.mkAnd((BoolExpr)nctx.recv.apply(y, politoVpnExit, p_1, t_1),
+													    ctx.mkLt(t_1, t_0),
+													    (BoolExpr)nctx.pf.get("encrypted").apply(p_1),
+													    ctx.mkEq(nctx.pf.get("src").apply(p_1), vpnAccessIp),
+													    ctx.mkEq(nctx.pf.get("dest").apply(p_1), vpnExitIp),
+													    ctx.mkEq(nctx.pf.get("inner_src").apply(p_1), nctx.pf.get("src").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("inner_dest").apply(p_1), nctx.pf.get("dest").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("origin").apply(p_1), nctx.pf.get("origin").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("orig_body").apply(p_1), nctx.pf.get("orig_body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("body").apply(p_1), nctx.pf.get("body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("seq").apply(p_1), nctx.pf.get("seq").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("proto").apply(p_1), nctx.pf.get("proto").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1), nctx.pf.get("emailFrom").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("url").apply(p_1), nctx.pf.get("url").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("options").apply(p_1), nctx.pf.get("options").apply(p_0))), 1, null, null, null, null))),
+			1,null,null,null,null);
+
+		constraints.add(constraint1);
+
+		BoolExpr constraint2 = ctx.mkForall(new Expr[]{t_0, p_0, x},
+				ctx.mkImplies(ctx.mkAnd(
+									  (BoolExpr)nctx.send.apply(politoVpnExit, x, p_0, t_0),
+									  ctx.mkNot(ctx.mkEq(nctx.pf.get("inner_src").apply(p_0), nctx.am.get("null")))),
+							  ctx.mkAnd(
+									  ctx.mkEq(nctx.pf.get("src").apply(p_0), vpnExitIp),
+									  ctx.mkEq(nctx.pf.get("dest").apply(p_0), vpnAccessIp),
+									  (BoolExpr)private_addr_func.apply(nctx.pf.get("dest").apply(p_0)),
+									  ctx.mkNot(ctx.mkEq(nctx.pf.get("inner_dest").apply(p_1), vpnExitIp)),
+									  (BoolExpr)nctx.pf.get("encrypted").apply(p_0),
+									  ctx.mkExists(new Expr[]{y, p_1, t_1},
+											  ctx.mkAnd((BoolExpr)nctx.recv.apply(y, politoVpnExit, p_1, t_1),
+													    ctx.mkLt(t_1, t_0),
+													    ctx.mkNot((BoolExpr)nctx.pf.get("encrypted").apply(p_1)),
+													    ctx.mkEq(nctx.pf.get("src").apply(p_1), nctx.pf.get("inner_src").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("dest").apply(p_1), nctx.pf.get("inner_dest").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("inner_src").apply(p_1), nctx.am.get("null")),
+													    ctx.mkEq(nctx.pf.get("inner_dest").apply(p_1), nctx.am.get("null")),
+													    ctx.mkEq(nctx.pf.get("origin").apply(p_1), nctx.pf.get("origin").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("orig_body").apply(p_1), nctx.pf.get("orig_body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("body").apply(p_1), nctx.pf.get("body").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("seq").apply(p_1), nctx.pf.get("seq").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("proto").apply(p_1), nctx.pf.get("proto").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("emailFrom").apply(p_1), nctx.pf.get("emailFrom").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("url").apply(p_1), nctx.pf.get("url").apply(p_0)),
+													    ctx.mkEq(nctx.pf.get("options").apply(p_1), nctx.pf.get("options").apply(p_0))), 1, null, null, null, null))),
+				1,null,null,null,null);
+
+		constraints.add(constraint2);
+	}
+
+	public void setInternalAddress(ArrayList<DatatypeExpr> internalAddress){
+    	List<BoolExpr> constr = new ArrayList<BoolExpr>();
+    	Expr n_0 = ctx.mkConst("vpn_node", nctx.address);
+
+    	for(DatatypeExpr n : internalAddress){
+    		constr.add(ctx.mkEq(n_0,n));
+    	}
+    	BoolExpr[] constrs = new BoolExpr[constr.size()];
+    	//Constraint		private_addr_func(n_0) == or(n_0==n foreach internal address)
+    	constraints.add(ctx.mkForall(new Expr[]{n_0}, ctx.mkEq(private_addr_func.apply(n_0),ctx.mkOr(constr.toArray(constrs))),1,null,null,null,null));
+    }
+
+}
\ No newline at end of file
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoWebClient.java b/verigraph/service/src/mcnet/netobjs/PolitoWebClient.java
new file mode 100644
index 0000000..28e2cf2
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoWebClient.java
@@ -0,0 +1,107 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+
+/**
+ * WebClient
+ */
+public class PolitoWebClient extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr politoWebClient;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoWebClient(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+		    isEndHost=true;
+	   		constraints = new ArrayList<BoolExpr>();
+			z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+			politoWebClient = z3Node;
+			net = (Network)args[0][1];
+			nctx = (NetContext)args[0][2];
+			DatatypeExpr ipServer = (DatatypeExpr) args[0][3];
+			webClientRules(ipServer);
+			//net.saneSend(this);
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return politoWebClient;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+//			System.out.println("[MailClient] Installing rules.");
+			BoolExpr[] constr = new BoolExpr[constraints.size()];
+			solver.add(constraints.toArray(constr));
+		}
+
+	    private void webClientRules (DatatypeExpr ipServer){
+	    	Expr n_0 = ctx.mkConst("PolitoWebClient_"+politoWebClient+"_n_0", nctx.node);
+	    	Expr p_0 = ctx.mkConst("PolitoWebClient_"+politoWebClient+"_p_0", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst("PolitoWebClient_"+politoWebClient+"_t_0");
+
+	    	//Constraint1		send(politoWebClient, n_0, p, t_0) -> nodeHasAddr(politoWebClient,p.src)
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoWebClient, n_0, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoWebClient,nctx.pf.get("src").apply(p_0))),1,null,null,null,null));
+
+			//Constraint2		send(politoWebClient, n_0, p, t_0) -> p.origin == politoWebClient
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoWebClient, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("origin").apply(p_0),politoWebClient)),1,null,null,null,null));
+
+			//Constraint3		send(politoWebClient, n_0, p, t_0) -> p.orig_body == p.body
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoWebClient, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),1,null,null,null,null));
+
+			//Constraint4		recv(n_0, politoWebClient, p, t_0) -> nodeHasAddr(politoWebClient,p.dest)
+			constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,politoWebClient, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(politoWebClient,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+
+			//Constraint5		This client is only able to produce HTTP requests
+			//					send(politoWebClient, n_0, p, t_0) -> p.proto == HTTP_REQ
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoWebClient, n_0, p_0, t_0),
+                        ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_REQUEST))),1,null,null,null,null));
+
+            //Constraint6		send(politoWebClient, n_0, p, t_0) -> p.dest == ipServer
+            constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(politoWebClient, n_0, p_0, t_0),
+                            ctx.mkEq(nctx.pf.get("dest").apply(p_0), ipServer)),1,null,null,null,null));
+	    }
+	}
diff --git a/verigraph/service/src/mcnet/netobjs/PolitoWebServer.java b/verigraph/service/src/mcnet/netobjs/PolitoWebServer.java
new file mode 100644
index 0000000..54710d9
--- /dev/null
+++ b/verigraph/service/src/mcnet/netobjs/PolitoWebServer.java
@@ -0,0 +1,114 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Politecnico di Torino and others.
+ *
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Apache License, Version 2.0
+ * which accompanies this distribution, and is available at
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *******************************************************************************/
+
+package mcnet.netobjs;
+
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.microsoft.z3.BoolExpr;
+import com.microsoft.z3.Context;
+import com.microsoft.z3.DatatypeExpr;
+import com.microsoft.z3.Expr;
+import com.microsoft.z3.FuncDecl;
+import com.microsoft.z3.IntExpr;
+import com.microsoft.z3.Solver;
+
+import mcnet.components.NetContext;
+import mcnet.components.Network;
+import mcnet.components.NetworkObject;
+/**
+ * WebServer object
+ *
+ */
+public class PolitoWebServer extends NetworkObject{
+
+		List<BoolExpr> constraints;
+		Context ctx;
+		DatatypeExpr node;
+		Network net;
+		NetContext nctx;
+		FuncDecl isInBlacklist;
+
+		public PolitoWebServer(Context ctx, Object[]... args) {
+			super(ctx, args);
+		}
+
+		@Override
+		protected void init(Context ctx, Object[]... args) {
+			this.ctx = ctx;
+		    isEndHost=true;
+	   		constraints = new ArrayList<BoolExpr>();
+	        z3Node = ((NetworkObject)args[0][0]).getZ3Node();
+	        node = z3Node;
+	        net = (Network)args[0][1];
+	        nctx = (NetContext)args[0][2];
+	        webServerRules();
+	    }
+
+		@Override
+		public DatatypeExpr getZ3Node() {
+			return node;
+		}
+
+		@Override
+		protected void addConstraints(Solver solver) {
+				BoolExpr[] constr = new BoolExpr[constraints.size()];
+			    solver.add(constraints.toArray(constr));
+		}
+
+	    private void webServerRules (){
+	    	Expr n_0 = ctx.mkConst("webserver_"+node+"_n_0", nctx.node);
+	    	Expr p_0 = ctx.mkConst("webserver_"+node+"_p_0", nctx.packet);
+	    	Expr p_1 = ctx.mkConst("webserver_"+node+"_p_1", nctx.packet);
+	    	IntExpr t_0 = ctx.mkIntConst("webserver_"+node+"_t_0");
+	    	IntExpr t_1 = ctx.mkIntConst("webserver_"+node+"_t_1");
+
+	    	//Constraint1		send(politoWebServer, n_0, p, t_0) -> nodeHasAddr(politoWebServer,p.src)
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(node,nctx.pf.get("src").apply(p_0))),1,null,null,null,null));
+
+	    	//Constraint2		send(politoWebServer, n_0, p, t_0) -> p.origin == politoWebServer
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("origin").apply(p_0),node)),1,null,null,null,null));
+
+	    	//Constraint3		send(politoWebServer, n_0, p, t_0) -> p.orig_body == p.body
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
+                    		ctx.mkEq(nctx.pf.get("orig_body").apply(p_0),nctx.pf.get("body").apply(p_0))),
+                    1,null,null,null,null));
+
+	    	//Constraint4		recv(n_0, politoWebServer, p, t_0) -> nodeHasAddr(politoWebServer,p.dest)
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.recv.apply(n_0,node, p_0, t_0),
+                    		(BoolExpr)nctx.nodeHasAddr.apply(node,nctx.pf.get("dest").apply(p_0))),1,null,null,null,null));
+
+	    	//Constraint5
+			//	    			send(politoWebServer, n_0, p, t_0)  ->
+			//	    			(exist p_1,t_1 :
+			//	    	    		(t_1 < t_0 && recv(n_0, politoWebServer, p_1, t_1) &&
+			//	    	     		p_0.proto == HTTP_RESP &&  p_1.proto == HTTP_REQ &&
+			//	    	     		p_0.dest == p_1.src && p_0.src == p_1.dest &&  p_0.url == p_1.url)
+	    	constraints.add( ctx.mkForall(new Expr[]{n_0, p_0, t_0},
+                    ctx.mkImplies((BoolExpr)nctx.send.apply(node, n_0, p_0, t_0),
+                        ctx.mkExists(new Expr[]{p_1, t_1},
+                            ctx.mkAnd(
+                            		ctx.mkLt(t_1, t_0),
+                            		ctx.mkEq(nctx.pf.get("url").apply(p_0), nctx.pf.get("url").apply(p_1)),
+                            		(BoolExpr)nctx.recv.apply(n_0, node, p_1, t_1),
+                            		ctx.mkEq(nctx.pf.get("proto").apply(p_0), ctx.mkInt(nctx.HTTP_RESPONSE)),
+                            		ctx.mkEq(nctx.pf.get("proto").apply(p_1), ctx.mkInt(nctx.HTTP_REQUEST)),
+                            		ctx.mkEq(nctx.pf.get("dest").apply(p_0), nctx.pf.get("src").apply(p_1)),
+                            		ctx.mkEq(nctx.pf.get("src").apply(p_0), nctx.pf.get("dest").apply(p_1))),
+                            1,null,null,null,null)),1,null,null,null,null));
+	    }
+}