Queueing And Scheduling On Egress Queues - Cisco 3750G - Catalyst Integrated Wireless LAN Controller Configuration Manual

Chapter 33 Configuring QoS

Queueing and Scheduling on Egress Queues

Figure 33-9
If the expedite queue is enabled, SRR services it until it is empty before servicing the other three queues.
Note
Figure 33-9
(DSCP or CoS value).
Determine egress queue
number and threshold
Queue the packet. Service
the queue according to
Rewrite DSCP and/or
Each port supports four egress queues, one of which (queue 1) can be the egress expedite queue. These
queues are assigned to a queue-set. All traffic exiting the switch flows through one of these four queues
and is subjected to a threshold based on the QoS label assigned to the packet.
OL-8550-02
shows the queueing and scheduling flowchart for egress ports.
Queueing and Scheduling Flowchart for Egress Ports
Start
Receive packet from
the stack ring.
Read QoS label
based on the label.
Yes
Are thresholds
being exceeded?
No
the SRR weights.
CoS value as
appropriate.
Send the packet
out the port.
Done
Drop packet.
Catalyst 3750 Switch Software Configuration Guide
Understanding QoS
33-17