A low delay multi-source multicast algorithm for ad hoc networks

In this paper, we present a multi-source multi-cast algorithm for wireless ad hoc networks. As a tree-based routing approach, it forms a tree connecting source(s) to the multicast destinations. Our algorithm ensures that each multicast destination gets packets from the shortest path that has the minimum numbers of hops to its nearest source. Our approach is multi-source support and fully distributed. We also extend our algorithm to provide an alternative tree to improve its robustness for networks with frequent link failures and node mobility. With extensive simulations on a large set of network instances in different scenarios, we show that our algorithm has lower end to end delay and shorter hop distance than the well-known tree-based multicast algorithm MAODV, although the total number of transmissions is slightly larger than MAODV. Moreover, under low to moderate node mobility the delay performance of our approach is virtually unaffected.