Joint multipath rate control and scheduling for SVC streams in wireless mesh networks

Rate adaptation of video signal for different quality-of-service scenarios through scalable video coding (SVC) standard has been considered as a key feature for multimedia transmission. This paper addresses joint multipath rate control and scheduling for SVC-encoded video transmission over wireless mesh networks (WMNs). Each video stream is assumed to use multipath routing and to possess a staircase utility function. Using the conflict graph that represents the interference-limited model, we formulate the problem as one of maximising the sum of source utilities subject to transport and link layers constraints. The multipath routing over wireless channels and staircase utilities yield a non-convex optimisation problem. To attain a convex formulation, we adopt multimodal sigmoid approximation and exploit utility-proportional fairness approach. Then, employing dual decomposition, we devise a distributed algorithm for joint multipath rate control and scheduling in WMNs. Experiments validate the effectiveness of our endeavor toward achieving cross-layer optimisation for video transmission in WMNs.