Improved AODV Routing Protocol For Mobile Ad-hoc Network Life Time Maximization

Ad hoc network is a collection of wireless mobile nodes forming a temporary network with out the aid of any stand-alone infrastructure or centralized administration. Because of the dynamic nature of nodes in the said network, it is termed as Mobile Ad hoc Network (MANET). Such improvised network is self-organizing and self-configuring multi-hop wireless network where, the structure of network changes erratically.One of the main design constraints in MANETs is that they are energy constrained. For this reason, every effort channeled towards energy efficiency. More precisely, network lifetime is a key design metric in MANETs. Since every node has to perform the functions of a router, if some nodes die early due to lack of energy, it will not be possible for other nodes to communicate with each other. Hence, the network gets disconnected and the network lifetime adversely affected. To maximize the lifetime of these networks, the residual energy in each mobile node along the path well managed and its use must considered in design of routing protocols.The intermittent connectivity of mobile ad hoc network makes the design of routing protocol full of twists and turns. Even though the large amount of routing protocols developed to alleviate such precarious problem, none of them provided single solution. Still need modification/improvement ever more. In this research, focus made on reactive on-demand distance vector routing protocol, which called as AODV (Ad hoc on-demand Distance Vector). Among others, this protocol has promising features while it does not concern about issue of network lifetime. Hence, the aim of this research is to modify traditional AODV for prolonged existence of network lifetime in mobile ad hoc network where nodes are operating on battery power alone and batteries cannot recharged. To this end, we proposed and analyzed modified routing protocol, which termed as Maximum Residual Energy Multi-paths AODV (MREMP-AODV). The protocol argues that using the energy oblivious path all the time will deplete the energy of nodes on that path and shortens network lifetime.MREMP-AODV routing protocol primarily uses maximum residual energy of nodes participating along the path. Rooted in these residual energy of nodes, establishes and uses multi-paths (primary and alternate paths), but not simultaneously, avoiding single short path routing by careful coupling of maximum residual energy and multi-paths. In the course of route discovery, intermediate nodes append their residual energy to RREQ packet. In addition, exceptions added to the role of destination and source nodes. Predominantly, the maximum residual energy of nodes participating along the path will be a decisive condition when selecting the routes. It initiates route re- discovery only when all the paths fail. Hence, avoidance of frequent route discovery contributes to reduction of packet delay and the amount of routing packets in network. Truly, the performance of MREMP-AODV confirmed by simulation results illustrated in chapter 4. Thus, MREMP-AODV out performs the traditional AODV and prolongs the existence of network lifetime significantly.