Cisco WS-C2916M-XL Software Guide - Page 211

Chapter 7 Configuring the Switch Ports Configuring Voice Ports Configuring Voice Ports The Catalyst 2900 XL and Catalyst 3500 XL switches can connect to Cisco IP Phonesand carry IP voice traffic. If necessary, the Catalyst 3524-PWR XL can supply electrical power to the circuit connecting it to the phone. For information about Catalyst 3524-PWR XL inline power, see the "Configuring Inline Power on the Catalyst 3524-PWR Ports" section on page 7-15. Because the sound quality of an IP telephone call can deteriorate if the data is unevenly sent, the switch uses quality of service (QoS) based on IEEE 802.1p class of service (CoS). QoS uses classification and scheduling to send network traffic from the switch in a predictable manner. The Cisco IP Phone or access point itself is also a configurable device, and you can configure it to forward traffic with an 802.1p priority. You can use the CLI to configure the Catalyst 3524-PWR XL to honor or ignore a traffic priority assigned by a Cisco IP Phone or access point. For example, the Cisco 7960 IP Phone contains an integrated three-port 10/100 switch. The ports are dedicated connections to these devices: • Port 1 connects to the Catalyst 3524-PWR XL switch or other voice-over-IP device. • Port 2 is an internal 10/100 interface that carries the phone traffic. • Port 3 connects to a PC or other device. Figure 7-2 shows one way to configure a Cisco 7960 IP Phone. Figure 7-2 Cisco 7960 IP Phone Connected to a Catalyst 3524-PWR XL Switch Catalyst PC 3524-PWR XL Cisco 7960 IP Phone IP 33048 802.1Q trunk Preparing a Port for a Cisco IP Phone Connection Before you configure a Catalyst 3524-PWR XL port to carry IP voice traffic, configure the port as an 802.1Q trunk and as a member of the voice VLAN (VVID). See the "Configuring a Trunk Port" section on page 8-28 for instructions. 78-6511-08 Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide 7-13