An Efficient Encoding Tree for Location-Aware Multicast Routing Protocol in Wireless Ad Hoc Networks

Abstract

A mobile ad hoc network (Manet) is a collection of mobile nodes moving arbitrarily and dynamically, and also bases on wireless links for router interconnection. In order to facilitate communication between mobile group nodes in Manet, a multicast routing protocol is used to discover routers between nodes. As we know, the spanning tree (a tree graph) is used in multicast routing to produce a loop-free and an efficient forwarding path for datagram in the IP layer. However, tree graph optimization problems are usually difficult and time consuming NP-hard or NP-complete problems. Our Sequence and Topology encoding for multicast protocol (STMP) is introduced for multicast routing in wireless Ad Hoc networks and generalizes the graph optimization problem of tree-based multicast protocol. Another objective is also to find a multicast routing mechanism that reduces the number of packet forwarding and improves the efficiency of ad hoc networks routing scheme in such a dynamical environment. The resulting multicast tree based on this mechanism is then encoded by using Sequence and Topology encoding with two integer sequences which we can determine four statuses of each node to transmit packets efficiently. The protocol has been simulated in ad hoc networks using NS2 simulator form 20 to 120 nodes and with different multicast group sizes. We show that the proposed protocol delivers packets to all the nodes in a destination group in more than 87% of the cases. Furthermore, compared to flooding and Prüfer encoding algorithm, our protocol achieves improvement of up to 50% on multicast completion delay. STMP is also more efficient for scaleable ad hoc networks.