On the Scalability of Many-to-Many Reliable Multicast Sessions

Even though tree-based reliable multicast protocols are known to be most scalable for one-to-many sessions, there is still an open question whether these protocols are also scalable for many-to-many sessions. In this paper, we analyze and compare two promising multicast protocols the receiver-initiated protocol with NACK suppression and the tree-based protocol using a new spatial loss model. The proposed model considers the correlation of packet loss events for more realistic analysis unlike the previous work. The analysis results show that the tree-based protocol achieves much higher throughput than the receiver-initiated protocol for a many-to-many session as the number of participants in the session becomes larger.