Congestion control in network layer occurs when a node or link carries data beyond its limit. This often leads to the queuing of packets—and in the worst case, loss of packets—as well as a decrease in the network's Quality of Service (QoS).

For congestion detection wireless sensor networks generally uses one or more of the four mechanisms use (i) Buffer queue length (ii) channel loading time (iii) Reporting rate and (iv)The packet service time by packet interarraival time ration.

TCP short for Transmission Control Protocol is the most dominant protocol used in computer networking and on the Internet. Characteristically, TCP encompasses various features, one of them is congestion control. window is 16 KB, then the transmission would occur at 8 KB.

Thereafter, when there is congestion, block time sharing, dynamic allocation without time slicing, dynamic allocation time slicing with signal sensing, frequently recent call allocation, and priority allocation algorithms were developed to manage the congestion.