Cisco WS-C2960S-24PD-L Software Guide - Page 212

Configuring Voice Ports Chapter 7 Configuring the Switch Ports Configuring a Port to Connect to a Cisco IP Phone Because a Cisco IP Phone also supports connection to a PC or other device, a port connecting a Catalyst 3524-PWR XL switch to a Cisco IP Phone can carry mixed traffic. There are three configurations for a port connected to a Cisco IP Phone: • All traffic is sent according to the default COS priority of the port. This is the default. • Voice traffic is given a higher priority by the phone, and all traffic is in the same VLAN. • Voice and data traffic are carried on separate VLANs, and voice traffic always has a CoS priority of 5. Beginning in privileged EXEC mode, follow these steps to configure a port to instruct the phone to give voice traffic a higher priority and to forward all traffic through the 802.1Q native VLAN: Step 1 Step 2 Step 3 Step 4 Step 5 Command Purpose configure terminal Enter global configuration mode. interface interface Enter interface configuration mode, and enter the port to be configured. switchport voice vlan dot1p Instruct the switch port to use 802.1p priority tagging for voice traffic and to use VLAN 0 (default native VLAN) to carry all traffic. end Return to privileged EXEC mode. show interface interface switchport Verify the port configuration. Overriding the CoS Priority of Incoming Frames A PC or other data device can connect to a Cisco IP Phone port. The PC can generate packets with an assigned CoS value. If you want, you can use the Catalyst 3524-PWR XL CLI to override the priority of frames arriving on the phone port from connected devices. You can also set the phone port to accept (trust) the priority of frames arriving on the port. Beginning in privileged EXEC mode, follow these steps to override the CoS priority setting received from the nonvoice port on the Cisco IP Phone: Step 1 Step 2 Step 3 Step 4 Step 5 Command Purpose configure terminal Enter global configuration mode. interface interface Enter interface configuration mode, and enter the switch port to be configured. switchport priority extend cos 3 Set the phone port to override the priority received from the PC or the attached device and forward the received data with a priority of 3. end Return to privileged EXEC mode. show interface interface switchport Verify the change. Use the no switchport priority extend command to return the port to its default setting. 7-14 Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide 78-6511-08