Patent ID: 7142513

Claim:
A method for managing network packet traffic with minimum performance guarantees and maximum service rate control, comprising the steps of: a) assigning each of a plurality of output buffer queues with a reserved weight in bandwidth sharing of an output link, each of the output buffer queues being associated with a respective service class; b) optionally assigning at least one of the output buffer queues with a maximum rate to constrain packet transmission through said at least one of the output buffer queues; c) enqueueing incoming packets in the output buffer queues according to associated service classes of the incoming packets; d) determining in real-time shared bandwidth rates of maximum-rate constrained backlogged ones of the output buffer queues with reference to the reserved weights of the backlogged ones of the output buffer queues and such that the shared bandwidth rate of each maximum-rate constrained backlogged one of the output buffer queues does not exceed the maximum rate which is assigned thereto; and e) transmitting outgoing packets from the backlogged ones of the output buffer queues in accordance with a schedule that is based on the shared bandwidth rates determined in step d); wherein each of the output buffer queues is a first-in, first-out buffer queue, said method further comprising, prior to step e), the step of calculating virtual starting and virtual finishing times for the packet at the head of each of the backlogged ones of the output buffer queues to determine when the packet should start and finish servicing, the virtual starting and virtual finishing times being calculated with reference to the reserved weights of the output buffer queues and the shared bandwidth rates determined in step d).