A Multiple Description Coding strategy for Multi-Path in Mobile Ad hoc Networks

One of the main challenges for mobile ad hoc networks is to design routing protocols that cope efficiently with dynamic network topologies. In this paper, we propose a routing strategy in a multipath context and adapted to proactive protocols like OLSR. The main idea is to use the sizeable amount of information collected by every node in order to select not one but several reliable routes used simultaneously. Then, the information is not merely parcelled out between these routes, but coded using a Multiple Description method, which reduces the dependency on topology changes. Each route among the N selected ones is used to transmit a specific description. Any subset of M routes among these N routes is sufficient to rebuild the initial data information. Furthermore, thanks to path diversity, the local bitrate is reduced. This feature may be interesting in the case of multimedia information exchanges (such as video) over mobile ad hoc networks. Performance analysis of this new algorithm shows that the paths reliability is improved. In particular, load balancing for high bitrates and dense networks enables to reach interesting performances.