Changes between Initial Version and Version 1 of Ticket #1253


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Timestamp:
05/28/14 13:42:53 (10 years ago)
Author:
hdempsey@bbn.com
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  • Ticket #1253 – Description

    initial v1  
    77
    88One of the aims of network engineering is to configure forwarding rules of the switches as to guarantee network compliance with the Packet Forwarding Policies (PFP). VERMONT is a software toolset that provides some automation to the solution of this task by checking consistency of OpenFlow rule tables with formally specified invariants of PFP.
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    910VERMONT can be installed in line with the control plane to observe state changes of a network by intercepting messages sent by switches to the controller and commands sent by the controller to switches. It builds an adequate formal model of a whole network and checks every event, such as installation, deletion, or modification of rules, port and switch up and down events, against the requirements of PFP. Before a network update command is sent to a switch VERMONT checks in advance the result of its execution. If a new state of network satisfies all  requirements of PFP then the command is delivered to the corresponding switch. Upon detecting a violation of PFP VERMONT blocks the update command, alerts a network administrator, and gives some additional information to discover a possible source of an error.
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    1012VERMONT has a wide area of applications. It can be attached to a SDN controller (or a bunch of controllers) to enforce basic safety properties (the absence of loops, blackholes, etc) of the subordinate flow-tables in data plane. VERMONT may be also used as a fully automatic safeguard (and, in a sense, a debugger) for any software application implementing certain PFP on a SDN controller. This properties make VERMONT a desired tool for network administrators and control application developers.
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