Performance Evaluation of Routing Protocols in Wireless Mobile Ad Hoc Networks (MANETS) using OPNET Simulator

ABSTRACT: Mobile ad hoc networks (MANETs) have already opened a new point of view in the field of wireless networks which includes hundreds and thousands of nodes. The wireless nodes are communicating without the need of any kind of neither infrastructure like the base stations or routers, nor centralized administration. Wireless nodes are free of moving anytime, anywhere. Therefore, mobile ad hoc networks need to have dynamic routing protocols. Mobile Ad hoc network routing protocols are divided into several different categories such as Proactive, Reactive and Hybrid Routing Protocols. Also there are a lot of performance metrics to compare the routing protocols. Each of them has its own attributes and well for specific area, such as: throughput, jitter, packet delivery ratio, average number of hops, route discovery time and end-to-end delay, which are some important ones. In this thesis three well known routing protocols; Optimized Link State Routing (OLSR), Ad-hoc On-demand Distance Vector (AODV) and Temporary Ordered Routing Algorithm (TORA) were evaluated using the OPNET simulator under the medium load traffic size in FTP protocol. The first one (OLSR) is a proactive protocol depending on routing tables which are maintained at each node. The second one (AODV) is a reactive protocol, that finds a route to a destination on-demand. And the third ones‘ TORA which works in both categories as reactive and proactive. The random waypoint mobility model is used as pattern of mobility. As performance metrics average throughput, average network load and average end-to-end delay are examined in different number of nodes, file sizes and node speeds. The result from the simulations of this study reveals that different protocols have different qualities; some of the protocols perform better than others in one metric when using them in a specific scenario and worse in other metrics. After analyzing performances of some well-known reactive and proactive routing protocols, in case of average throughput, average end-to-end delay and average network load, the superiority of proactive protocols, over reactive ones is observed in different network scenarios. From the simulation results it is observed that the average end-to-end delay increases slightly when the number of nodes increases in OLSR. Also average throughput shown in OLSR was the highest comparing to AODV and TORA. Among the reactive protocols, AODV performs better than TORA when file sizes, speed of nodes and number of nodes are changed. On the other hand, TORA gives a highest end-to-end delay and lowest throughput compared to AODV and OLSR. Keywords: Mobile wireless ad hoc networks, simulation, routing protocols, performance evaluation, OPNET simulator. …………………………………………………………………………………………………………………………