Congestion Control based on Geographic Routing Algorithm for Wireless Sensor Networks

Resource control is a branch of congestion control in wireless sensor networks (WSNs). The congestion-oriented resource control schemes in WSNs often re-route traffic loads to avoid the congested areas. The re-routing overhead for congestion avoidance is particularly large in large networks. Thus, this kind of congestion control lacks of strong scalability. In this paper, a congestion control based on a geographic routing algorithm (CcbGr) for WSNs is proposed. It determines the congestion status of a node using thresholds of the queue length and the changing rate of the queue length. We adopt a geographic forwarding scheme in avoiding congestion. A new algorithm of distance update is also proposed to by-pass routing holes which are common for geographic routing. When a node is on the edge of a hole, it will increase the distance between itself and the sink according to specific rules. Simulation results show that CcbGr can effectively address network congestion with high scalability.