Cisco IE 3000 User Manual

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Cisco IE 3000 Switch Software Configuration Guide
OL-13018-01
Chapter 32 Configuring QoS
Understanding QoS
Queueing and Scheduling on Ingress Queues
Figure 32-7 shows the queueing and scheduling flowchart for ingress ports.
Figure 32-7 Queueing and Scheduling Flowchart for Ingress Ports
Note 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.
Table 32-1 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
Ye s
No
Ta b l e 32-1 Ingress Queue Types
Queue Type
1
1. The switch uses two nonconfigurable queues for traffic that is essential for proper network operation.
Function
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.

Cisco IE 3000 Specifications

General

Brand	Cisco
Model	IE 3000
Category	Switch
Language	English