Multipath coded routing protocol for event-driven wireless sensor networks

An intra-flow network coding based opportunistic multipath routing protocol called CodePaths is proposed referring to the Burst-Bulk characteristic of traffic in event-driven wireless sensor networks. In CodePaths, a new routing metric, taking delay and congestion factors into account, is defined and implemented for establishing routing gradient field from nodes to sink. When an event occurs in the network area, nodes employ random linear network coding and recoding to mix packets, and assign 'forwarding opportunities' to downstream nodes based on the routing gradients and link qualities. Consequently, an interleaving-paths mesh is constructed, along which the encoded packets are routed and finally decoded by the sink node. The extensive simulation results indicate that CodePaths can well adapt to the randomness of events. Compared with other single and multi-path routing, CodePaths with higher throughput and lower latency minimizes the data transmission and energy consumption while keeps the packet delivery rate over 95%.