| US 7,525,917 B2 | ||
| Flow control in a distributed scalable, shared memory switching fabric system | ||
| Philip Ferolito, Sunnyvale, Calif. (US); Eric Anderson, Palo Alto, Calif. (US); and Gregory S. Mathews, Santa Clara, Calif. (US) | ||
| Assigned to Acatel-Lucent USA Inc., Murray Hill, N.J. (US) | ||
| Filed on Jun. 04, 2003, as Appl. No. 10/453,975. | ||
| Claims priority of provisional application 60/385981, filed on Jun. 04, 2002. | ||
| Prior Publication US 2003/0223448 A1, Dec. 04, 2003 | ||
| Int. Cl. G01R 31/08 (2006.01); H04L 12/28 (2006.01) | ||
| U.S. Cl. 370—236.1 [370/236.2; 370/413] | 13 Claims |
| 1. A method of controlling traffic flow across a switching fabric, comprising:
receiving cells at the switching fabric from an ingress of a first packet processor module coupled to the switching fabric;
enqueuing the cells in a plurality of queues within the switching fabric;
dequeuing the cells from the plurality of queues;
forwarding the cells to an egress of a second packet processor module;
aggregating respective numbers of cells dequeued for each queue;
sending a flow control message (FCM) from the switching fabric to the ingress of the first packet processor module, in accordance
with a scheduling algorithm, wherein the FCM comprises one or more of the respective numbers of cells dequeued;
resetting the one or more respective numbers of cells dequeued;
combining the FCM and at least one of the cells, wherein said sending further includes directing the FCM from the switching
fabric toward the ingress of the first packet processor module via the egress of the second packet processor module;
separating the FCM and the at least one cell at the egress; using the FCM to decrement write counters at the ingress;
reassembling a packet using the cell; and
send the packet from the egress.
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