An efficient routing algorithm for multicasting in a large network

In this paper we introduce a new multicast routing algorithm to be used in a large network. The proposed algorithm is a hybrid of the core based tree (CBT) and protocol independent multicast-sparse mode (PIM-SM) and builds a bidirectional shared tree centered around a rendezvous point and shortest path trees rooted at some senders. Multicast messages are distributed along the bidirectional shared tree and the shortest path trees and, therefore, the message delivery delay is lower than both the CBT and the PIM-SM.