SIGNALLING CONGESTION

摘要

Methods and apparatus for signalling congestion are described, in respect of a network element (10) operable to forward received data items in a telecommunications networks such as the Internet, and in respect of a processing element operable to process received requests for service. In either case, the element is operable to perform its processing function at up to a processing rate which is subject to variation, and has a queue for items awaiting processing having a counter associated therewith which maintains a count from which a queue metric is derivable. The method comprises: updating the count at a rate dependent on the processing rate (32, 50); further updating the count in response to receipt of items awaiting processing (32, 50); and signalling a measure of congestion in respect of the element in dependence on the queue metric (34, 36, 50). The method further comprises (i) altering the rate at which the count is being updated (54) and (ii) adjusting the counter whereby to cause a change in the queue metric (54) if it is determined (52) that the processing rate has changed.

主权项

1) A method of processing data items received at a network element in a communications network, the network element being operable to forward data items at a rate up to a forwarding rate, the forwarding rate being subject to variation; the network element having a queue for data items awaiting forwarding and having a counter associated therewith, the counter maintaining a count in dependence on which a queue metric is derivable according to a predetermined algorithm; the method comprising:
updating the count at a rate dependent on the forwarding rate; further updating the count in response to receipt of data items; and signalling a measure of congestion in respect of the network element in dependence on said queue metric;the method being characterised by further comprising:
determining if there has been a variation in the forwarding rate, and in response to a determination that there has been a variation in the forwarding rate:
altering the rate at which the count is being updated in accordance with the variation in the forwarding rate; andadjusting the counter in dependence on the variation in the forwarding rate whereby to cause a change in the queue metric.