Loop freedom of the (untimed) AODV routing protocol

Timothy Bourke 🌐 and Peter Höfner 🌐

October 23, 2014

This is a development version of this entry. It might change over time and is not stable. Please refer to release versions for citations.

Abstract

The Ad hoc On-demand Distance Vector (AODV) routing protocol allows the nodes in a Mobile Ad hoc Network (MANET) or a Wireless Mesh Network (WMN) to know where to forward data packets. Such a protocol is ‘loop free’ if it never leads to routing decisions that forward packets in circles.

This development mechanises an existing pen-and-paper proof of loop freedom of AODV. The protocol is modelled in the Algebra of Wireless Networks (AWN), which is the subject of an earlier paper and AFP mechanization. The proof relies on a novel compositional approach for lifting invariants to networks of nodes.

We exploit the mechanization to analyse several variants of AODV and show that Isabelle/HOL can re-establish most proof obligations automatically and identify exactly the steps that are no longer valid.

License

BSD License

Topics

Session AODV