FLOW CONTROL IN NETWORK DEVICES

摘要

Methods and apparatus are provided for controlling flow rates of a plurality of data packet flows into a queue 4 corresponding to a resource 3 of a netwo rk device 1. The flows comprise a set 7 of non-responsive flows, and a set 8 of other flows which may comprise responsive flows and/or flows whose responsiveness is unknown. The flow rates are managed in accordance with a queue management scheme such that adjustments are made to each flow rate in dependence on excess bandwidth in the resource, the amounts of the adjustmen ts being dependent on one or more adjustment parameters for each flow. An error signal is generated based on the deviation from a desired allocation ratio o f the ratio of the total flow rates into the queue 4 for the sets of flows 7, 8. At least one adjustment parameter for at least one flow is then varied in dependence on the error signal in such a manner as to reduce the aforementioned deviation. A closed-loop control scheme thus operates in conjunction with the underlying queue management scheme to promote fair bandwidth allocation even in the presence of a mix of responsive and non- responsive flows.