WRED drops packets
selectively based on
precedence. IP precedences are assigned to packets as they enter the
network. WRED uses these
to determine how to treat different types of traffic.
Configure WRED using the
random-detect command and different CoS, DSCP,
EXP, and discard-class values. The value can be range or a list of values that
are valid for that field. You can also use minimum and maximum queue thresholds
to determine the dropping point.
When a packet arrives, the
following actions occur:
The average queue size is
queue size is less than the minimum queue threshold, the
arriving packet is queued.
queue size is between the minimum queue threshold for that
type of traffic and the maximum threshold for the interface, the packet is
either dropped or queued, depending on the packet drop probability for that
type of traffic.
queue size is greater than the maximum threshold, the packet
You cannot configure WRED in
a class that has been set for priority queueing (PQ).
You cannot use the
random-detect command in a class configured with