基于密度树的P2P视频流多播

应用层多插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插模型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，实现应用层多插．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．

P2P Scheme for the Media Stream Multicast Based on Density Tree

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.