  Network congestion has become a critical issue for resource constrained
Wireless Sensor Networks (WSNs), especially for Wireless Multimedia Sensor
Networks (WMSNs)where large volume of multimedia data is transmitted through
the network. If the traffic load is greater than the available capacity of the
sensor network, congestion occurs and it causes buffer overflow, packet drop,
deterioration of network throughput and quality of service (QoS). Again, the
faulty nodes of the network also aggravate congestion by diffusing useless
packets or retransmitting the same packet several times. This results in the
wastage of energy and decrease in network lifetime. To address this challenge,
a new congestion control algorithm is proposed in which the faulty nodes are
identified and blocked from data communication by using the concept of trust.
The trust metric of all the nodes in the WMSN is derived by using a two-stage
Fuzzy inferencing scheme. The traffic flow from source to sink is optimized by
implementing the Link State Routing Protocol. The congestion of the sensor
nodes is controlled by regulating the rate of traffic flow on the basis of the
priority of the traffic. Finally we compare our protocol with other existing
congestion control protocols to show the merit of the work.
