| Description | The Queue Table enumerates the queues on an interface.
Queues are used to store traffic during intervals when
the arrival rate exceeds the departure rate for a class
of traffic. Because some PHBs indicate that the use of
a priority queue may be advisable, each queue in this
system is seen as having a priority. Those queues that
share the same priority operate in what may externally
appear to be a Weighted Round Robin manner, and preempt
the traffic belonging to any lower priority. For this
reason, it is strongly urged that traffic placed into
prioritized queues be strongly policed to avoid traffic
lockout.
Queues in this table also have a minimum and a maximum
rate. When a maximum rate is specified, the queue acts
as a shaper if it has sufficient traffic and capacity
is available. If it is a minimum rate, then the weight
in the WRR is effectively set to this rate divided by
the sum of the rates of queues on the interface,
guaranteeing it at least that throughput rate. If it is
a maximum rate, the queue operates as a shaper. A
shaper potentially reduces the rate of traffic through
it to the indicated rate, and minimizes variations in
rate. |