基于密度树的应用层多播算法

The Application Level Multicast Based on Density Tree

在IP多播的路由器上转发数据,存在一些弊端并不适应当前网络的需要,在终端主机上选择路由进行多播已经成为目前的趋势。为此,本文在IHC算法上进行优化改进,提出一种新的DHCM(density-basedhierarchicalclus-teringmulticast)应用层多播模型,DHCM对Cluster的密度进行层次划分,使Cluster满足单调性和同构性,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。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 muhicast 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 seletion 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.