lp Eng Arc Cqc Ov Port Congestion Policy

This attribute specifies the congestion behavior of all ports on this FP. It applies only to transmit traffic served on the common queues and does not apply to per-VC queues. When the value is aggregate, the enqueue decision of cells or frames to a common queue is based upon the congestion state of the entire port to which the queue belongs. A port is defined to be as congested as the most congested queue amongst all its common queues: the low, medium and high emission priority queues. Thus, for example, if the low priority queue is congested, the high priority queue also experiences discards even though the high priority queue may itself not be congested. Setting this attribute to aggregate assures that the low priority queues are also serviced in the event of congestion. When the value of this attribute is set to individualQueue, the enqueue decision of cells or frames to a common queue is based solely upon the congestion state of that queue, not the port. This setting assures that the absolute priority of the traffic is taken into account, regardless of whether the lower priority queues are being served.