A congestion notification mechanism provides a congestion status for all destinations in a switch at each ingress port. Data is stored in a memory subsystem queue associated with the destination port at the ingress side of the crossbar. A cell credit manager tracks the amount of data in this memory subsystem...http://www.google.fr/patents/US20050088969?utm_source=gb-gplus-shareBrevet US20050088969 - Port congestion notification in a switch
