基于密度树的P2P视频流多播

P2P Scheme for the Media Stream Multicast Based on Density Tree

应用层多播技术是互联网研究的一个重要方向.本文提出一种新的应用层多播模型DHCM,该模型采用改进的IHC算法,对cluster的密度进行层次划分,通过组建一个密度树实现最短路由,并把peer-to-peer技术用在数据传输上,最终把视频服务器的内容分发到密度树上的各个主机,实现应用层多播.这种密度层次划分的cluster满足单调性和同构性.实验证明DHCM可以在视频流传输上具有高效性和健壮性.

Currently IP multicast copies and transmits data in router so that it cannot meet the demand for its disadvantages, and it is a trend that multicast is realized through route selection at end hosts. This paper has proposed a new model of application level multicast named DHCM （Density-based Hierarchical Clustering Multicast）which has improved IHC arithmetic. DHCM divides the hosts into many hierarchies according to their density, and constructs a density tree to realize the shortest routing. The tree delivers the content of video server to each host in density tree and uses a p2p scheme in data transmission. By this way the application-level multicast has been realized. This density tree has the homogeneity and monotonic properties. The experiment result has proved that DHCM can transmit the video stream efficiently and robustly.