Patent ID: 6697330
Filing Date: 2004-02-24
Classification: H04L

Abstract:
A method for initiating flow control in a network multiplexer that forwards a message descriptor referencing a communications packet received by a receiving port to one or more transmit queues, each transmit queue associated with a transmitting port which transmits communications packets queued to the transmit queue, the method comprising:providing each transmitting port in the network multiplexer with a high threshold and a low threshold; when a message descriptor is queued to a transmit queue associated with a transmitting port, when the transmit queue currently contains a maximum number of message descriptors, discarding the message descriptor, and when the transmit queue currently contains a number of message descriptors equal to or greater than the high threshold of the associated transmitting port, sending a flow control request to the receiving port that received the communications packet referenced by the queued message descriptor, and when the transmit queue currently contains a number of message descriptors greater than or equal to the low threshold of the associated transmitting port, but the number of message descriptors contained in the transmit queue exceeded or equaled the high threshold of the associated transmitting port more recently than the number of message descriptors contained in the transmit queue was equal to the low threshold of the associated transmitting port, sending a flow control request to the receiving port that received the communications packet referenced by queued message descriptor.