Metod och anordning för flödesstyrning i paketförmedlande nät

摘要

A control system in an ATM system controls flows of data cells and flow control management cells from a number of sources to a destination over connections passing a network element. The flow control management cells are returned from the destination via the network element to their respective sources. The network element is exposed to congestion due to contention between the connections, that necessitates queuing of the connections. The flow control management cells have an explicit rate field for an explicit rate value used to limit a source maximum allowed cell rate to a specific value. An operating function uses deviations from an available rate value for lower priority cells and from a queue length reference forming a desirable queue length, to calculate a modified explicit rate value as a function of these deviations. This modified explicit rate value is introduced into the explicit rate field of the backward flow control management cells.