TSLA: A QoS-Aware On-Demand Routing Protocol for Mobile Ad Hoc Networks

The complexity of Mobile Ad Hoc Networks (MANETs) has led to the extensive research in the development of their routing protocols as reported in literature. Although most of the proposed routing protocols are based on the shortest path algorithm, some other metrics like load and network congestion have also been considered in some other research. However, with the introduction of traffic differentiation in IEEE 802.11e, congestion effect becomes more distinct as the nodes with delay-sensitive multimedia applications tend to be busy for prolonged periods. This has received little attention in the literature to date. In this paper, we first expose that the performance of MANETs routing protocols is highly dependent on the type of traffic generated or routed by intermediate nodes. We then propose Type of Service and Load Aware routing protocol (TSLA), an enhancement to AODV that uses both the traffic load and the type of service as additional metrics. To our knowledge, TSLA is the first to avoid congestion by distributing the load over a potentially greater area and conducting the traffic through less busy nodes and, therefore, less congested routes. Our simulation study reveals a persistent improvement in throughput and packet delay of both low and high priority traffic.