IL-CD: Interference and load aware congestion detection and bandwidth efficient rate allocation for wireless mesh networks

In this paper, we investigate the issue of congestion avoiding in wireless mesh networks, which involves two main challenges, how to detect early congestion and how to adjust transmitting rates to maximize network throughput. In WMNs, interference among neighboring contending links can adversely affect performance of TCP-like congestion control protocol. Since TCP do not account for links interdependency within a neighborhood, network throughput degrades drastically and severe unfairness occurs. In our work, we aim to find the effective bandwidth of a link considering the contention within neighborhood and real time traffic load towards the link. Our proposed link load and interference aware congestion detection mechanism, IL-CD finds the achievable bandwidth of transmitting links considering the current congestion and traffic intensity level of the neighborhood. For avoiding congestion, we design a distributed rate controller that fairly divides this estimated capacity to contending flows. Experiments conducted on ns-2 simulations demonstrate that our proposed algorithm can achieve significant improvements in both overall network throughput and inter-flow fairness.