Patent ID: 8681609

Claim:
A method of transmitting a plurality of traffic flows to N output ports through a switch during a scheduling interval, comprising: receiving each of said plurality of traffic flows, each of said plurality of traffic flows associated with a respective guaranteed data rate; buffering packets in each of said plurality of traffic flows in one of N input queues, in dependence on the output port for that traffic flow; in a switching interval, transmitting a packet from a chosen traffic flow from a selected one of said N input queues to the output port for that selected one of said N input queues; wherein said chosen traffic flow is chosen as having the largest positive normalized service lag among traffic flows having buffered packets in said selected one of said N input queues, determined over a period of time from the beginning of the scheduling interval until the beginning of the switching interval; wherein the normalized service lag of each traffic flow reflects the difference between the amount of traffic that could be transmitted at said flow's guaranteed data rate during said period and the amount of traffic from said flow transmitted through said switch during said period.