Multi-path selection for multiple description video streaming over overlay networks

摘要

Real-time media distribution over the Internet poses several challenging problems due to its stringent delay/loss requirements and complex network dynamics. A promising approach to alleviate the severe impacts of these dynamics is to transmit the media over diverse paths. For such an environment, multiple description (MD) coding has been previously proposed to produce multiple independently decodable streams that are routed over partially link–disjoint (non-shared) paths for combatting bursty packet losses and error propagation. However, selecting these paths appropriately is fundamental to the success of MD streaming and path diversity. Hence, in this paper we develop models for MD streaming over multiple paths and based on these models we propose a multi-path selection method that chooses a set of paths maximizing the overall quality at the client under various constraints. The simulation results with MPEG-2 show that sizeable average peak signal-to-noise ratio (PSNR) improvements (ranging from 0.73 to 6.07 dB) can be achieved when the source video is streamed over intelligently selected multiple paths as opposed to over the shortest path or maximally link–disjoint paths. In addition to the PSNR improvement, end-users experience a more continual, i.e., uninterrupted, streaming quality. Our work also considers the architecture and mechanisms by which multi-path streaming can be accomplished over a conventional IP network.