| 摘要 |
A system (10) and method for performing event based rate policing using varying window start times. Rate policing overhead, including counter and timer monitoring and resetting, is performed only as needed and in response to actual received traffic on each connection. As the last bit of a data unit is received from an external network, an "event time stamp" is generated and associated with the data unit, for example as part of an internal header or trailer attached to the data unit. To determine if a rate policing window was active when the frame was received, the event time stamp is compared with the sum of a window start time and a window period value stored in association with the connection on which the unit was received. If the associated event time stamp indicates a time error prior to the sum of the associated window start time and window period, then a rate policing window is determined to have been active when the frame was received. In that case, rate policing is performed on the received frame with respect to the active rate policing window. If the rate policing window was not active when the frame was received, then a new rate policing window is started, and the frame is rate policed in a new rate window, which is started at a time equal to the event time stamp associated with the received frame.
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