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diff --git a/docs/userguide/04-vtc-overview.rst b/docs/userguide/04-vtc-overview.rst new file mode 100644 index 000000000..82b20cad5 --- /dev/null +++ b/docs/userguide/04-vtc-overview.rst @@ -0,0 +1,122 @@ +.. This work is licensed under a Creative Commons Attribution 4.0 International +.. License. +.. http://creativecommons.org/licenses/by/4.0 +.. (c) OPNFV, National Center of Scientific Research "Demokritos" and others. + +========================== +Virtual Traffic Classifier +========================== + +Abstract +======== + +.. _TNOVA: http://www.t-nova.eu/ +.. _TNOVAresults: http://www.t-nova.eu/results/ +.. _Yardstick: https://wiki.opnfv.org/yardstick + +This chapter provides an overview of the virtual Traffic Classifier, a +contribution to OPNFV Yardstick_ from the EU Project TNOVA_. +Additional documentation is available in TNOVAresults_. + +Overview +======== + +The virtual Traffic Classifier (:term:`VTC`) :term:`VNF`, comprises of a +Virtual Network Function Component (:term:`VNFC`). The :term:`VNFC` contains +both the Traffic Inspection module, and the Traffic forwarding module, needed +to run the :term:`VNF`. The exploitation of Deep Packet Inspection +(:term:`DPI`) methods for traffic classification is built around two basic +assumptions: + +* third parties unaffiliated with either source or recipient are able to +inspect each IP packet’s payload + +* the classifier knows the relevant syntax of each application’s packet +payloads (protocol signatures, data patterns, etc.). + +The proposed :term:`DPI` based approach will only use an indicative, small +number of the initial packets from each flow in order to identify the content +and not inspect each packet. + +In this respect it follows the Packet Based per Flow State (term:`PBFS`). This +method uses a table to track each session based on the 5-tuples (src address, +dest address, src port,dest port, transport protocol) that is maintained for +each flow. + +Concepts +======== + +* *Traffic Inspection*: The process of packet analysis and application +identification of network traffic that passes through the :term:`VTC`. + +* *Traffic Forwarding*: The process of packet forwarding from an incoming +network interface to a pre-defined outgoing network interface. + +* *Traffic Rule Application*: The process of packet tagging, based on a +predefined set of rules. Packet tagging may include e.g. Type of Service +(:term:`ToS`) field modification. + +Architecture +============ + +The Traffic Inspection module is the most computationally intensive component +of the :term:`VNF`. It implements filtering and packet matching algorithms in +order to support the enhanced traffic forwarding capability of the :term:`VNF`. +The component supports a flow table (exploiting hashing algorithms for fast +indexing of flows) and an inspection engine for traffic classification. + +The implementation used for these experiments exploits the nDPI library. +The packet capturing mechanism is implemented using libpcap. When the +:term:`DPI` engine identifies a new flow, the flow register is updated with the +appropriate information and transmitted across the Traffic Forwarding module, +which then applies any required policy updates. + +The Traffic Forwarding moudle is responsible for routing and packet forwarding. +It accepts incoming network traffic, consults the flow table for classification +information for each incoming flow and then applies pre-defined policies +marking e.g. :term:`ToS`/Differentiated Services Code Point (:term:`DSCP`) +multimedia traffic for Quality of Service (:term:`QoS`) enablement on the +forwarded traffic. +It is assumed that the traffic is forwarded using the default policy until it +is identified and new policies are enforced. + +The expected response delay is considered to be negligible, as only a small +number of packets are required to identify each flow. + +Graphical Overview +================== + +.. code-block:: console + + +----------------------------+ + | | + | Virtual Traffic Classifier | + | | + | Analysing/Forwarding | + | ------------> | + | ethA ethB | + | | + +----------------------------+ + | ^ + | | + v | + +----------------------------+ + | | + | Virtual Switch | + | | + +----------------------------+ + +Install +======= + +run the build.sh with root privileges + +Run +=== + +sudo ./pfbridge -a eth1 -b eth2 + +Development Environment +======================= + +Ubuntu 14.04 |