Patent ID: 7408876

Claim:
A system to control congestion across a switched backplane comprising: a packet forwarding device in a network, the packet forwarding device having a plurality of blades and a switched backplane, the plurality of blades each having a throughput per blade, wherein some of the throughput per blade is used to connect the blade to the switched backplane and some of the throughput per blade is used to connect the blade to the network; a first blade, a second blade, and a third blade, the blades coupled via the switched backplane; a first egress queue associated with the first blade and a second egress queue associated with the second blade, the first and the second egress queues mapped to the third blade, the first and the second queues each having a depth and a packet dequeuing rate; and a memory element to store a queue threshold associated with the first and the second egress queues; wherein the first blade to reduce the packet rate of dequeuing the first egress queue and to notify the second blade that the first egress queue is congested, when the depth of the first egress queue exceeds the queue threshold; and wherein, in response to the notification, the second blade to reduce the packet rate of dequeuing the second egress queue until the depths of the first egress queue and the second egress queue are both below the queue threshold.