Cisco Systems 3560 사용자 설명서

 shows the queueing and scheduling flowchart for ingress ports.

SRR services the priority queue for its configured share before servicing the other queue.

The switch supports two configurable ingress queues, which are serviced by SRR in shared mode only. 

 describes the queues.

90564

Read QoS label

(DSCP or CoS value).

Determine ingress queue
number, buffer allocation,

and WTD thresholds.

Are thresholds

being exceeded?

Queue the packet. Service

the queue according to

the SRR weights.

Send packet to

the internal ring.

Drop packet.

Start

Yes

No

1.

The switch uses two nonconfigurable queues for traffic that is essential for proper network operation.

Normal 

User traffic that is considered to be normal priority. You can configure three different thresholds to 
differentiate among the flows. You can use the mls qos srr-queue input threshold, the mls qos srr-queue 
input dscp-map, and the mls qos srr-queue input cos-map global configuration commands.

Expedite

High-priority user traffic such as differentiated services (DF) expedited forwarding or voice traffic. You can 
configure the bandwidth required for this traffic as a percentage of the total traffic by using the mls qos 
srr-queue input priority-queue global configuration command. The expedite queue has guaranteed bandwidth.