Dynamic rate allocation and opportunistic routing for scalable video multirate multicast over time-varying wireless networks

In this paper, we consider the time-varying characteristics of practical wireless networks, and propose a joint dynamic rate allocation and transmission scheduling optimization scheme for scalable video multi-rate multicast based on opportunistic routing (OR) and network coding. With OR, the decision of optimal routes for scalable video coding (SVC) layered streaming is integrated into the joint optimization formulation. The network throughput is also increased by taking advantage of the broadcast nature of the wireless shared medium and by network coding operations in intermediate nodes. To maximize the overall video reception quality among all destinations, the proposed scheme can jointly optimize the video reception rate, the associated routes to different destinations, and the time fraction scheduling of transmitter sets that are concurrently transmitting in the shared wireless medium. By using dual decomposition and primal-dual update approach, we develop a cross-layer algorithm in a fully distributed manner. Simulation results demonstrate significant network multicast throughput improvement and adaptation to dynamic network changes relative to existing optimization schemes.