Patent ID: 9215174
Filing Date: 2015-12-15
Classification: H04L

Abstract:
1. A method for oversubscription control of a rack switch, the method comprising: receiving a packet through one of a plurality of ingress ports of the rack switch from a source; providing the packet to an oversubscription buffer of the rack switch that is common to the plurality of ingress ports; providing a copy of the packet to a virtual oversubscription buffer; monitoring an occupancy level of the virtual oversubscription buffer to determine a utilization level of the oversubscription buffer; comparing, by circuitry of the rack switch, the occupancy level of the virtual oversubscription buffer with a utilization threshold; configuring, by the circuitry, a congestion notification of a subsequent packet provided to the oversubscription buffer from the source when the occupancy level of the virtual oversubscription buffer is equal to or exceeds the utilization threshold; transmitting, by the circuitry, the congestion notification to the source of the subsequent packet; and providing, by the circuitry when the occupancy level of the virtual oversubscription buffer is equal to or exceeds the utilization threshold, the subsequent packet to a destination that is configured to transmit an acknowledgement of the subsequent packet to the source, the acknowledgement including an indication of the congestion notification, wherein the congestion notification indicates that congestion is present in the oversubscription buffer.