Cisco Systems 2960

29-21

Catalyst 2960 Switch SoftwareConfiguration Guide

78-16881-01

Chapter29 Configuring QoS

Configuring Auto-QoS

•When you enter the auto qos voip cisco-softphone interface configuration command on a port at

the edge of the network that is connected to a device running the Cisco SoftPhone, the switch uses

policing to determine whether a packet is in or out of profile and to specify the action on the packet.

If the packet does not have a DSCP value of 24, 26, or 46 or is out of profile, the switch changes the

DSCP value to 0. The switch configures ingress and egress queues on the port according to the

settings in Table29-3 and Ta ble 29 -4.

•When you enter the auto qos voip trust interface configuration command on a port connected to the

interior of the network, the switch trusts the CoS value for nonrouted ports in ingress packets (the

assumption is that traffic has already been classified by other edge devices). The switch c onfigures

the ingress and egress queues on the port according to the settings in Table29-3 and Table 29-4.

For information about the trusted boundary feature, see the “Configuring a Trusted Boundary t o

Ensure Port Security” section on page 29-35.

When you enable auto-QoS by using the auto qos voip cisco-phone, the auto qos voip cisco-softphone,

or the auto qos voip trust interface configuration command, the switch automatically generates a QoS

configuration based on the traffic type and ingress packet label and applies the commands listed in

Table29-5 to the port.

Table29-5 Generated Auto-QoS Configuration

Description Automatically Generated Command

The switch automatically enables standard QoS and configures

the CoS-to-DSCP map (maps CoS values in incoming packets

to a DSCP value).

Switch(config)# mls qos

Switch(config)# mls qos map cos-dscp 0 8 16 26 32 46

48 56

The switch automatically maps CoS values to an ingress queue

and to a threshold ID.

Switch(config)# no mls qos srr-queue input cos-map

Switch(config)# mls qos srr-queue input cos-map

queue 1 threshold 3 0

Switch(config)# mls qos srr-queue input cos-map

queue 1 threshold 2 1

Switch(config)# mls qos srr-queue input cos-map

queue 2 threshold 1 2

Switch(config)# mls qos srr-queue input cos-map

queue 2 threshold 2 4 6 7

Switch(config)# mls qos srr-queue input cos-map

queue 2 threshold 3 3 5

The switch automatically maps CoS values to an egress queue

and to a threshold ID.

Switch(config)# no mls qos srr-queue output cos-map