Proxy caching based on segments for layered encoded video over the Internet

In the multimedia system, the video server has limited streaming capacities and may be far away from the clients. In order to achieve higher user capacity and lower network transmission cost, proxy cache can be used, which are located close to the user and in which popular video objects are likely to be cached. In this paper, as a result of the heterogeneity of accessing the Internet, we propose a novel scheme that is used to distribute layered encoded video by proxy cache based on segments, which popularity derives from the popularity of inter-video clip and intra-video clip as well as distribution of users´ downstream bandwidth. Our simulation results show that the proposed proxy caching scheme based on segments can greatly reduce the server´s bit ratios with a cache of given capacity, and enhance the capability of adapting to the heterogeneity of the Internet while not increasing the implementation complexity. Moreover our method can cache more first segments of video clip layers, which results in the ability to reduce start-up latency greatly.