Wireless sensor network (WSN) plays an important role in many application areas like in military surveillance, health care etc. A WSN is deployed with a large number of sensor nodes in a wide geographical area. These nodes collect information depending on type of the application and transmit the data towards the sink node. When a large number of sensor nodes are engaged in transmitting data, there is a possibility of congestion in the network. Congestion is one of the critical issues in WSNs because it has direct impact on energy efficiency of sensor nodes, and the application’s throughput. Congestion degrades overall channel capacity and increases packet loss rate. In order to handle these problems, an efficient congestion control mechanism required. a number of congestion control mechanism have been proposed in literatures. Any congestion control mechanism consists of congestion detection, congestion notification and rate adjustment mechanisms. Some of the mechanisms reviewed in this paper are CODA, PCCP, FACC, Fusion, Siphon, QACC and UHCC. We discuss pros and cons of each of these mechanisms.

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Wireless sensor network congestion control energy efficient