A cross-layer optimized error recovery mechanism for real-time video in ad-hoc networks

The increase in the bandwidth of wireless channels and the computing power of mobile devices increase the interest in video communications over ad-hoc wireless networks. However, the high error rate and the rapidly changing quality of the radio channels can be devastating for the transport of compressed video. In addition, the bounded playout delay for interactive video limits the effectiveness of retransmission-based error control. In this paper, we propose an error recovery mechanism for real-time video that combines forward error correction (FEC), and multi-path retransmission. Based on the sender to receiver route obtained from lower layers, as well as the video data content, the mechanism determines the allocation of error correction code, as well as the retransmission criteria. We evaluated the effectiveness of the mechanism under different network conditions. Simulation results show that the proposed hybrid error recovery mechanism maintains the video quality under different loss rates and mobility speeds, with less overhead compared to error recovery methods that depend only on fixed FEC allocation.