Simulation with different Ad Hoc network scenarios of routing protocols in MANETs using OPNET simulator

Mobile Ad hoc Networks (MANETs) are dynamic wireless networks with no fixed infrastructure, where mobile nodes operate as both hosts and routers. The absence of centralized infrastructure, frequent topology changes, and limited bandwidth resources present challenges for routing. Various routing protocols have been developed to address these challenges, notably AODV, DSR, and OLSR. This study presents a comparative performance analysis of AODV, DSR (reactive protocols), and OLSR (a proactive protocol), using the OPNET Modeler simulation tool. Performance is evaluated under varying traffic loads, network sizes, and node mobility, with FTP traffic used to mimic realistic applications. Key performance metrics include average end-to-end delay and throughput. The results show that throughput improves, and end-to-end delay increases with larger network sizes and higher traffic loads. However, mobility does not significantly impact performance in larger networks. Among the protocols, OLSR shows superior performance in terms of end-to-end delay, while AODV outperforms others in throughput. DSR exhibits inconsistent delay behavior, particularly under heavy load and larger networks.