Alleviating Congestion Using Traffic-Aware Dynamic Routing in Wireless Sensor Networks

The congestion problem in wireless sensor networks (WSNs) is quite different from that in traditional networks. Most current congestion control algorithms try to alleviate the congestion by reducing the rate at which the source nodes inject packets into the network. However, this traffic control scheme always decreases the throughput so as to violate fidelity level required by the application. In this paper, we present a solution that sufficiently exert the idle or under-loaded nodes to alleviate congestion and improve the overall throughput. To achieve this goal, a traffic-aware dynamic routing(TADR) algorithm is proposed to route packets around the congestion areas and scatter the excessive packets along multiple paths consisting of idle and under-loaded nodes. Enlightened by the concept of potential in common physics, our TADR algorithm is designed through constructing a mixed potential field using depth and normalized queue length to force the packets to steer clear of obstacles created by congestion and eventually move towards the sink. The simulation results show that our solution achieves its objectives and improves the overall throughput by around 370% as compared to the benchmark routing protocol. Furthermore, our TADR has low overhead suitable for large scale dense sensor networks.