congestion management - Computer Definition
The process of managing a congestion condition. Congestion management mechanisms include the use of buffers that can be used to temporarily store data in one or more queues until the data can be forwarded through the internal bus or switching matrix of a switch or router, or through an outgoing port and across a communications link. As the buffers fill to capacity, data can be discarded, perhaps selectively based on a priority or quality of service (QoS) mechanism. If a network is configured as a mesh, a component router may have the ability to identify and exercise alternate paths if the primary path is suffering congestion levels that exceed definable parameters established in consideration of QoS objectives. Some network protocols provide for a router, for example, to advise its peers of congestion conditions and to instruct them to throttle back their transmission rates to avoid compounding the situation. Similarly, public network-based routers can advise customer edge routers to throttle back, or even temporarily suspend transmission of offered traffic until the congestion condition relaxes. Finally, a network-based router or switch can simply reject a call or message transmission. In a voice network, a PBX or central office (CO) provides the rejected caller with a fast busy signal.