Cisco Systems 3750E manual Configuring the Priority of Incoming Data Frames, 15-6

Chapter 15 Configuring Voice VLAN

Configuring Voice VLAN

This example shows how to configure a port connected to a Cisco IP Phone to use the CoS value to classify incoming traffic, to use IEEE 802.1p priority tagging for voice traffic, and to use the default native VLAN (VLAN 0) to carry all traffic:

Switch# configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Switch(config)# interface gigabitethernet1/0/1

Switch(config-if)# mls qos trust cos

Switch(config-if)#switchport voice vlan dot1p

Switch(config-if)# end

To return the port to its default setting, use the no switchport voice vlan interface configuration command.

This example shows how to enable switchport voice detect on a Cisco IP Phone:

Switch# configure terminal
Enter configuration commands,		one per line. End with CNTL/Z.
Switch(config)# interface fastethernet 0/1
Switch(config-if)# switchport		voice?
detect	detection enhancement keyword
vlan	VLAN for voice	traffic
Switch(config-if)# switchport		voice detect?
cisco-phone	Cisco IP Phone
Switch(config-if)# switchport		voice detect cisco-phone?
full-duplex	Cisco IP Phone
Switch(config-if)# switchport		voice detect cisco-phone full-duplex
full-duplex	full duplex keyword

Switch(config-if)# end

This example shows how to disable switchport voice detect on a Cisco IP Phone:

Switch# configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Switch(config)# interface fastethernet 0/1

Switch(config-if)#no switchport voice detect cisco-phone

Switch(config-if)#no switchport voice detect cisco-phone full-duplex

Configuring the Priority of Incoming Data Frames

You can connect a PC or other data device to a Cisco IP Phone port. To process tagged data traffic (in IEEE 802.1Q or IEEE 802.1p frames), you can configure the switch to send CDP packets to instruct the phone how to send data packets from the device attached to the access port on the Cisco IP Phone. The PC can generate packets with an assigned CoS value. You can configure the phone to not change (trust) or to override (not trust) the priority of frames arriving on the phone port from connected devices.

Beginning in privileged EXEC mode, follow these steps to set the priority of data traffic received from the nonvoice port on the Cisco IP Phone:

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	interface interface-id	Specify the interface connected to the Cisco IP Phone, and enter interface
		configuration mode.

Catalyst 3750-E and 3560-E Switch Software Configuration Guide

15-6 OL-9775-02