基于代理服务器缓存的Internet分层视频点播

Video on Demand Based on Proxy Caching for Layered Encoded Video over the Internet

针对目前访问Internet设备的差异性,为了降低网络传输成本,提出了一种基于视频分段的缓存算法来传输经过分层编码的视频流,其中分层视频段缓存优先级的计算来自于视频对象间的优先级、视频对象内的优先级以及用户接收带宽的分布.与缓存整个视频层的方案相比,仿真实验结果也证实了提出的针对分层视频流的缓存方案在给定缓存空间大小的情况下,可以大大降低视频服务器的点击率,而且在不增加实现复杂度的情况下也能满足用户接入带宽的差异性.

As a result of the heterogeneity of accessing the internet, in order to lower network transmission cost, a novel scheme that is used to distribute layered encoded video by proxy cache based on segments was proposed, whose priority derives from the priority of inter-video clip and intra-video clip as well as the distribution of users' downstream bandwidth. The simulation results show that compared with the caching video layer method, the proposed proxy caching scheme based on segments can greatly reduce the server's hit 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.