An Adaptive Congestion Control Strategy for Wireless

In wireless sensor networks, the nodes usually need satisfy the QoS requirement of forwarding the packets with different priorities. This way traffic flows are served in a differentiated manner, with higher priority traffic flows being allocated more bandwidth on the average than the lower priority traffic flows. This paper proposed an adaptive congestion control strategy for multi-hop WSNs. Two types of buffers in the relay nodes for the differentiated classes of flow are defined as the Premium flow and the Ordinary flow. The node periodically samples its queue occupancy and the packet rates of its upstream neighbors, and infers whether congestion will occur in the next interval. Upon receiving the congestion feedback, these upstream nodes decrease their rate according to the queue occupancies. The simulation results show that the proposed strategy can avoid the network congestion and jitter effectively, and obtain high utilization of the nodes´ capacity and buffer size.