Redundancy adaptation for multi-path intra-flow network coding in wireless mesh networks

Network coding can significantly enhance throughput and reliability in loss prone wireless networks. Adapting network coding redundancy is critical, since overredundancy wastes network resources and hurts performance and under-estimated redundancy prevents decoding at destination. In this paper, we study the tradeoff between application tolerated loss rate and network overhead introduced by network coding redundancy. We first propose an analytic model that determines a simple redundancy bound to adapt network coding redundancy according to the measured packet loss rate and the targeted maximum application loss rate. Then, we propose a distributed algorithm with adaptive redundancy for reliable data delivery in wireless meshes. In the algorithm, each node opportunistically makes use of multiple paths available in the network to deliver data to the destination. We demonstrate the benefits of our schemes through simulation in various network scenarios.