Local Repair and Next-hop Backup Route Based improvements in AODV Routing Protocol for Mobile Ad Hoc Networks

Abstract

As Mobile Ad hoc Networks (MANETs) continue to experience increasing popularity, several different protocols have been proposed to efficiently transmit data among the participating nodes. These protocols have to be robust and flexible to respond to the dynamic topology and decentralized nature of MANETS. The Ad hoc On Demand Distance Vector (AODV) Routing Protocol is one of the most commonly used reactive protocols for routing information in MANETS. Even though AODV performs well, it suffers from several shortcomings. This thesis aims to modify and upgrade the performance of AODV. Two different schemes are proposed which improve upon different aspects of the standard AODV routing protocol. In the first scheme, the AODV protocol is improved by adding the Local Repair feature. In this protocol, intermediate nodes in existing paths try to find new paths to the destination in the event of a link breakage. In the second scheme, Next-hop Backup Route is introduced. According to this scheme, once a path is established, every upstream node on an active route creates a backup path for its next-hop node. Thus, when link breakage happens, the upstream node can depend upon its backup node to forward the packet to the node that was previously its next-hop. Both these schemes increase the number of data packets successfully transmitted to the destination.