Distortion-Aware Multicasting of Multiple Description Coded Media in Wireless Mesh Networks

Traditional routing methods for multicasting traffic are mainly for single sessions, and their performance for multicasting bandwidth intensive media traffic in wireless mesh networks (WMNs) is limited by the end-to-end throughput of multi-hop transmissions. In this paper, we extend our earlier work [1] for multicasting media traffic that is encoded using multiple description coding (MDC) in WMNs by introducing a fully distributed scheme. The scheme relies on communications between one-hop neighbors to multiple multicast trees, each of which is rooted from one AP and delivers one description to some of the mobile stations (MSs) via the relay stations (RSs). The distortion of recovered media at an MS is determined by which description or descriptions have been correctly received. Our objective is to minimize the maximum distortion of recovered media at the MSs. This is achieved by taking advantage of the reduced bandwidth requirement of each description and the diversity gained from delivering multiple descriptions through different paths. Numerical results show that the proposed distributed scheme achieves good performance compared to the optimum solution and outperforms multicasting the source traffic directly.