Application level multicast in hierarchical topology

A application level multicast approach, hierarchical topology grouping (HTG), which exploits high level topology and IP address allocation information to build efficient overlay networks in a hierarchical topology is proposed. The topology is based on the underlying physical networks. The host in HTG uses the IP address position data to locate its appropriate domain, and uses the backbone roadmap to build the virtual links to connect the domains. All inter-domain connections are done without so much excessive measure traffic as other application level multicast approaches do. The characteristic of HTG make it suitable for multisource multicast naturally. We compare the HTG approach with the ESM and TAG approaches in a variety of simulation scenarios, including generated topologies and real Internet topology. Our results indicate the effectiveness of HTG in reducing measure traffic and transmit delay with reasonable calculation complexities.