Patent ID: 6771601
Filing Date: 2004-08-03
Classification: H04L

Abstract:
A method of flow control through a first network switch having a plurality of input ports and a plurality of output ports, the method comprising:receiving a message for transmission from an input port of the first network switch to an output port of the first network switch; determining if the received message results in an indication of congestion associated with transmitting the received message onto the output port; and pausing the transmission of messages received at a first input port on a second network switch which transmitted the received message using an output queue associated with an output port of the second network switch over which the received message was transmitted to the input port of the first network switch which received the message if the received message results in an indication of congestion; wherein said pausing the transmission comprises: transmitting a pause message from the first network switch to the second network switch which specifies a source and/or destination address of the received message; dividing the output queue of the second network switch into a plurality of sub-queues, wherein each sub-queue corresponds to one of a plurality of input ports which receive messages for transmission on the output port of the second network switch; storing messages received for transmission on the output port of the second network switch into one of the plurality of sub-queues based on the input port from which the message was received; determining the sub-queue corresponding to the source and/or destination address specified in the pause message so as to determine a paused sub-queue; and, pausing transmission of messages in the paused sub-queue on the output port of the second network switch while continuing to transmit messages from at least one sub-queue of the output port which is not paused.