Network Congestion

Meaning – The term network congestion, refers to an undesirable overload condition caused by traffic in excess of what a network can handle.

A consequence of congestion is that an incremental increase in offered load leads either only to a small increase or even a decrease in network throughput.

Network protocols that use aggressive retransmissions to compensate for packet loss due to congestion can increase congestion, even after the initial load has been reduced to a level that would not normally have induced network congestion. Such networks exhibit two stable states under the same level of load.

Example of usage“Networks use congestion control and congestion avoidance techniques to try to avoid collapse. These include exponential backoff in protocols such as CSMA/CA in 802.11 and the similar CSMA/CD in the original Ethernet, window reduction in TCP, and fair queueing in devices such as routers and network switches.”