Improved Transport Layer Protocol for Congestion Control in Wireless Sensor Networks

In wireless sensor networks, congestion occurs when multiple sensor nodes try to transmit data at the same time. Congestion may lead to packet drops and increased delay which in turn leads to lower throughput and delivery ratio. Thus congestion is an important aspect that should be considered while designing transport layer protocols for sensor networks. In this paper, we present an improved transport layer protocol for congestion control in wireless sensor networks. This protocol uses buffer size to detect congestion. Congestion is notified by overriding ACK packet with congestion information. Congestion is mitigated by adjusting transmission rates of congested nodes’ neighbors to optimal values. Simulation results show that this improved protocol provides an efficient congestion control mechanism and thus leads to increased throughput and delivery ratio with reduced delay and less energy loss as compared to CTCP.