Queue Length Aware Dynamic Source Routing Protocol for Mobile Ad Hoc Networks

Abstract

Mobile Ad-hoc Network was developed for short-term data communication in places with poor communication infrastructure; they do not rely on a centralized access point, infrastructure, or administration to meet the requirements for spontaneous network setup. They are distinguished by the use of wireless networks, constantly changing topologies, multi-hop connectivity, and decentralized routing and decision-making. The two most frequently researched on-demand ad hoc routing protocols are DSR and AODV. Previous research has indicated the limitations of these protocols in specific network conditions. Dynamic Source Routing (DSR) is a well-known routing protocol that has gained much attention due to its efficiency in MANETs. However, it does not take the queue length of the nodes into account when selecting a route in the next-hop node which leads to packet drop, congestion, and high delay in the network that reduces network performance. To address this issue, a Queue Length Aware Dynamic Source Routing Protocol (QLA-DSR) chooses next-hop nodes based on their queue lengths before forwarding packets are designed. In addition to the shortest path to the destination, the developed protocol considers the queue length of the intermediate nodes based on their buffer space availability and traffic load while selecting the next hop. In doing so, QLA-DSR aims to minimize the congestion and delay of the network, improving overall performance. Network Simulator (NS-3) is a simulating tool implemented to evaluate and compare its performance with other existing routing protocols DSR and AODV and the performance such as packet delivery ratio, and end-to-end delay, are used to compare QLA-DSR with other existing protocols. The successful implementation and evaluation of the QLA-DSR protocol contributes to developing efficient routing protocols for mobile ad hoc networks. Three simulation scenarios, the impact of varying network density, varying Numbers of Communicating Nodes, and varying Mobility Speeds of the Mobile Nodes are implemented, and performance matrices are evaluated. The finding of the simulation results of QLA-DSR when compared to DSR and AODV shows an average end-to-end delay improvement of 3.56 % and 4.54% respectively with the tradeoff routing overhead.