AN ENHANCED ROUTE FAILURE RECOVERY MODEL FOR MOBILE AD HOC NETWORKS

Abstract

In Mobile Ad Hoc Networks (MANET), change in topology of the network occurs due to the mobility factor of the nodes leading to the extension in size of the network. The extension of network size happens due to the entry of nodes into the network. As the topology changes, link failure between the nodes takes place due to several reasons like channel interference and dynamic obstacles etc that give rise to severe performance degradation. In traditional AODV, the link failure is overcome by re-routing from the source node which is a time consuming process that increases the overhead of the nodes. Also in case of multiple link failures, there are chances for loss of data packet. Maintaining the performance of the network dynamically during link failure, specifically in case of long data transfer such as the stream of voice data, is a challenging problem. In order to overcome such performance related issues, we developed the Local Link Failure Recovery algorithm (LLFR) for Ad hoc networks that establishes recovery from link failures spontaneously at the point of link breakage. In such cases, a reliable link failure recovery is the main criteria that will determine the performance of the network in terms of Quality of Service (QoS). The LLFR is deployed in each node collects RREP in the RREP Buffer Table (RBT) stack in the highest order of signal strength, which gets triggered during link failures. Once a link failure is detected, the intermediate node searches for an alternate path around the faulty area by choosing the first RREP that is stacked in the RBT and establishes a new route to the intended destination for sending the data packets without any time delay. The simulation results show that the performance parameters like packet delivery ratio, throughput, average end to end delay and routing overhead are better compared to the traditional AODV and other link failure recovery techniques.