Dropping or admitting packets to an output queue using policy-based scheduling and virtual destination queue occupancy values

摘要

One embodiment is associated with dropping or admitting packets to an output queue using occupancy values of virtual destination queues which are updated according to different independent disciplines upon the enqueuing of a packet to an output queue, and the dequeuing of that packet from an output queue. In one embodiment, a virtual destination queue is determined for a packet. A policing decision is made whether to drop the packet or admit the packet to the output queue based on the occupancy level of the determined virtual destination queue, which is updated upon admission. Packets are dequeued in first-in-first-out order from the output queue. For a dequeued one or more packets, one or more of the occupancy values of the virtual destination queues are updated based a scheduling policy that is independent of the particular virtual destination queue(s) associated with the dequeued packets.