STAMP: Shared-Tree Ad Hoc Multicast Protocol

Multicasting in mobile ad hoc networks (MANET) has received considerable attention and is extremely challenging due to the limited bandwidth and the dynamic topology characteristics of such networks (to name only a few). Moreover, the multicast capability of communications is going to be of great interest, especially in new military wireless environments for the digitized battlefield. Indeed, tactical MANETs, where large networks can be deployed, also add scalability constraints when designing a multicast routing protocol. Currently, the best response to scalability in ad hoc networks is to gather nodes into groups as a result of a clustering algorithm. The work of this paper focuses on solving the two related challenges: to achieve efficient and adaptive multicast communications firstly inside each cluster and secondly among the clusters. This paper presents a solution regarding the first challenge. We propose shared-tree ad hoc multicast protocol (STAMP), a core-based multicast routing protocol independent from the underlying unicast routing protocol. Compared to other shared-tree multicast protocols, STAMP achieves good performance even under mobility since it takes advantage from the broadcast capacity of the medium to deliver data on the tree (data forwarding based on mesh principles). Discrete event simulations were run to evaluate and to compare our method to other existing solutions