On-demand coding-aware routing in wireless Mesh networks

Network coding, which exploits the broadcast nature of wireless medium, is an effective way to improve network performance in wireless multi-hop networks, but the first practical wireless network coding system COPE cannot actively detect a route with more coding opportunities and limit the coding structure within two-hop regions. An on-demand coding-aware routing scheme (OCAR) for wireless Mesh networks is proposed to overcome the limitations specified above by actively detecting a route with more coding opportunities along the entire route rather than within two-hop regions. Utilizing more coding opportunities tends to route multiple flows 'close to each other' while avoiding interference requires routing multiple flows 'away from each other'. OCAR achieves a tradeoff by adopting as routing metric in route discovery, which is not only coding-aware but also considers both inter and intra flow interference. Simulation results show that, compared with Ad-hoc on-demand distance vecfor routing (AODV) and AODV+COPE, OCAR can find more coding opportunities, thus effectively increase network throughput, reduce end to end delay and alleviate network congestion.