Document No. 10-300077, Issue 2 25-35
80-Series QoS
Strict Priority Queueing
With strict priority queuing, the switch services the eight queues in order of
their priority. The highest priority queue is se rviced until it is empty, and
then the lower priority queues are serviced sequentially until they are
empty. For example, queue 7 must be empty before the switch services
queue 6. Queue 6 must be empty before the switch services queue 5. Queue
5 must be empty before the switch services queue 4, and so on.
For information on how to set up strict priority queueing, see “Setting Up
Strict Priority Queueing” later in this chapter.
CBQ
With the class-based queuing (CBQ) algorithm, you can specify a
maximum bit rate, or bandwidth, for a queue. When that bit rate is
exceeded, the switch drops all packets that exceed the bit rate.
The bit rate that you set should be the long-term average rate of
transmission. Traffic that does not exceed this rate is guaranteed transfer.
For information on how to set up CBQ queueing, see “Setting Up CBQ”
later in this chapter.
* Note: Avaya recommends that you do not se t a port using CBQ as the
source port or mirror port for a port mirror. When the switch
limits the bandwidth of a port, packets are subject to random
drop. If packets from a source port or mirror port are dropped,
the mirror traffic may not match the source traffic.
CBWFQ
The class-based weighted fair queueing (CBWFQ) algorithm is a
combination of the CBQ and WFQ algorithms. CBWFQ makes more
complex management of traffic possible. Using CBWFQ, you can set:
■The maximum bit rate.
The bit rate that you set should be the long-term average rate of
transmission. Traffic that does not exceed th is rate is guaranteed
transfer.
■Burst thresholds