EM-AODV: Metric based enhancement to AODV routing protocol

Abstract

Needless to say the importance of mobile ad-hoc networks has been increasing everyday because of its infrastructure-less, decentralized nature. Performance of an ad-hoc network mainly depends upon factors like path selection algorithm, power conservation strategy, quality of service schemes, and security mechanisms. Path selection is one of the main areas where many researchers are trying to improve the performance of the ad-hoc networks by proposing different routing protocols. Many ad-hoc network routing protocols choose the number of hops (shortest path) as the metric for data transfer which may not lead to stable paths. Thus, these unstable routes are prone to degrade the network performance. In this paper, the authors propose a new metric which takes the stability of the routes into consideration. A metric based enhanced version of ad-hoc on demand distance vector routing protocol (AODV) called enhanced metric based ad-hoc on demand distance vector protocol (EM- AODV) is presented. This new metric characterizes the stability of the paths by taking primarily three parameters viz. 'affinity, 'available bandwidth' and 'battery level' into routing decisions. The EM-AODV protocol maintains multiple paths to the destination in order to achieve load sharing. The performance of EM-AODV is compared with AODV in terms of data packet delivery ratio, number of route requests, control overhead, average number of packet drops, average end to end delay and average energy consumption. The protocol is backed by the simulations in GlomoSim that show an overall reduction in number of packet drops, route discovery frequency, control overhead and an increase in the packet delivery ratio.