Improving Performance of AODV using non-flooding route discovery technique

Abstract

Mobile Ad-hoc Network (MANET) is an infrastructure-less network (i.e., decentralized, selfconfiguring, and dynamic in nature). Nodes constitute the networks act as host (i.e., source and destination nodes) and router (i.e., intermediate nodes) interchangeably. One of the unique features that characterize MANETs is resource scarcity (i.e., nodes battery power and bandwidth is too limited). So to make the MANETs' protocols to perform efficiently regardless of change of topology the available bandwidth need to be used efficiently which can be achieved by optimizing the route discovery technique. Hence, the goal of this thesis is to optimize the performance of AODV by modifying its route discovery technique. The proposed route discovery technique improves the performance of AODV by minimizing unnecessary redundant control message, i.e., Route Request (RREQ) message. To minimize the unnecessary redundant control message during route discovery phase a non-flooding technique is integrated with the original AODV routing protocol. AODV is one of the well tested and documented reactive routing protocols and it is one of the typical examples of reactive routing protocols. AODV uses flooding technique on demand during a route discovery. Even if AODV generates less routing traffic when compared with proactive routing protocols problem arises when the number of nodes increases. Thus in this thesis, we replaced the flooding technique used in AODV with non-flooding, i.e. all nodes that receive RREQ packets will not rebroadcast RREQ packets in order to minimize redundant control messages. In our improved IAODV maximum node degree is used to rebroadcast RREQ packet. From the available neighbor nodes, the node with maximum node degree is chosen to rebroadcast RREQ packet. This minimizes the overhead that resulted during unnecessary and redundant exchange of RREQ packets in route discovery phase. This results in an efficient use of bandwidth. To evaluate the performance of the proposed work (i.e., IAODV)we have used Network Simulator Version 2.35 (NS2.35). The simulation result shows the reduction of Routing Overheadachieved through non-flooding technique improved Packet delivery ratio.