Cooperative Network Coding-Aware Routing for Multi-Rate Wireless Networks

Recent research has proven that network coding has great potential to improve network throughput in wireless networks. To fully exploit the performance gain brought by network coding, coding-aware routing has been studied to proactively change route of flows for creating more coding opportunities. However, in today's multi-rate wireless networks, coding may not be a wise decision as the lowest rate has to be used for coded information broadcasting, which causes significant resource waste for the high-rate links. In this paper, we propose the idea of cooperative network coding (CNC) to exploit spatial diversity for improving coding opportunity. We provide a theoretical formulation for calculating the maximal throughput of unicast traffic that can be achieved with CNC in multi-rate wireless networks. CNC-aware routing under both Alice-Bob and X-structure are discussed in this paper. The performance evaluation demonstrates that a CNC-aware route selection scheme that leverages cooperative communication to improve coding opportunity leads to higher end-to-end throughput comparing with the coding-oblivious and traditional coding-aware schemes.