Performance study of multicast routing protocol over manet

Abstract

Multicasting is intended for group-oriented communication services. One particularly challenging environment for multicast is a mobile ad-hoc network (MANET) where, the network topology can change randomly and rapidly, at unpredictable times. As a result, several specific multicast routing protocols for MANET have been proposed. Multicast approaches can generally be categorized into two: Proactive and On-Demand. The proactive approach pre-computes and maintains routes to all nodes, including nodes to which no packets are being sent. The on-demand approach creates the routes between nodes that are solely determined when they are explicitly needed to route packets. Multicasting protocols can also be categorized based on the structure used to forward multicast packets which are tree and mesh-based. The uses of on-demand routing approaches have been shown to have significant benefits in terms of reducing the routing protocol’s overhead. Therefore, this thesis focuses on performance of on-demand multicast routing protocols over MANET. More specifically, our concern is to characterize the merits of tree and mesh-based on-demand protocols over various ranges of MANET scenarios based on representative performance metrics. As a result, we are able to investigate the relative strengths, weaknesses and applicability of each protocol to diverse situation. For that reason, we particularly concentrate on NS-2 simulation of three protocols: MAODV, ODMRP and ADMR protocol. These protocols are the prominent on-demand multicast routing protocols in MANET as well as represent the tree and mesh-based protocols. Through simulation we demonstrate that though all these three protocols share similar on-demand behavior, the differences in routing structure leads to performance differentials. Based on evaluation, we make recommendation for the performance improvement of ODMRP protocol.