Transmission bandwidth quality of service

摘要

A bandwidth limiting circuit provides limiting the bandwidth of a group of virtual channels at a transmitting port to a maximum value. A limiting circuit includes a register that is repeatedly incremented with a threshold value, which threshold value is related to the desired maximum bandwidth for the group. The register is decremented by the frame length, in bytes, of the frame transmitted from one of the virtual channels belonging to the group. A comparator enables frame transmission for the group if the register value is greater than zero. A bandwidth guarantee circuit provides at least the bandwidth specified by the limiting circuit. The guarantee circuit enables one of the groups for frame transmission based on a fairness algorithm when the outputs of comparators of each of the limiting circuit are low.