Video-Aware Multipath Network Coding over Multi-hop Wireless Networks

Network coding has been shown to be an efficient approach for enhancing video streaming quality. With inter-session network coding, intermediate nodes will mix the media packets from different sources. However, packets from different flows may have different transmission rate and this will cause lack of coding opportunity for a period of time. So the relay nodes have to make a decision whether to forward packets directly or wait for the next opportunity to encode. In this paper, a prioritized network coding scheme is proposed to address the problem of mismatched coding opportunities in multiple streams. The base-layer packets of the streaming are received by the destination node with a high probability and the number of sent packets are reduced while taking full advantage of the limited network bandwidth. The experimental results show that the proposed scheme enhances the video quality compared to existing opportunistic coding schemes.