A novel and efficient source-path discovery and maintenance method for application layer multicast

Efficient and accurate source-path discovery is very important for the success of topology-aware application layer multicast. Topology-Aware Grouping (TAG), the typical topology-aware application layer multicast, only points out some methods can be used to get terminal node topology information. It does not give the specific description of which topology discovery method it adopts. The performance evaluation of the method is also not presented. Moreover, the required network environment of TAG is too idealistic. To solve the problems in previous work, we propose a novel source-path discovery method, called p-tracert. The basic idea is to discover and maintain gateway addresses and the connection information among gateways in a novel and efficient way. Performance analysis and simulation results show that p-tracert has the accuracy close to traditional traceroute, while p-tracert can reduce the topology discovery delay significantly.