Congestion-Aware Routing Scheme based on Traffic Information in Sensor Networks

In wireless sensor networks (WSNs), congestion introduces not only buffer overflow, but also transmission delay for message forwarding from the source node to the sink. In this paper, we propose a novel congestion-aware routing (CAW) scheme to reduce the packet end-to-end transmission delay while increasing network throughput. The proposed routing protocol is based on the geographic routing scheme. The relay node selection is determined by the sensor node location and the congestion condition in MAC layer of the local area. The proposed routing scheme utilizes the local area traffic information to select the next hop node so that the likelihood for traffic congestion and transmission delay can be minimized in the subsequent routing. The OPNET simulation results demonstrate that the proposed routing scheme can reduce the end-to-end packets transmission delay by 50% while increasing the network throughput for more than 2 times in our settings.