
14-3
Catalyst 3550 Multilayer Switch Software Configuration Guide
78-11194-09
Chapter 14 Configuring Voice VLAN
Configuring Voice VLAN
Voice VLAN Configuration Guidelines
These are the voice VLAN configuration guidelines:
•
You should configure voice VLAN on switch access ports.
•
Before you enable voice VLAN, we recommend that you enable QoS on the switch by entering the
mls qos global configuration command and configure the port trust state to trust by entering the mls
qos trust cos interface configuration command.
•
The Port Fast feature is automatically enabled when voice VLAN is configured. When you disable
voice VLAN, the Port Fast feature is not automatically disabled.
•
When you enable port security on an interface that is also configured with a voice VLAN, you must
set the maximum allowed secure addresses on the port to at least two.
•
If any type of port security is enabled on the access VLAN, dynamic port security is automatically
enabled on the voice VLAN.
•
You cannot configure static secure or sticky secure MAC addresses on a voice VLAN.
•
Voice VLAN ports can also be these port types:
–
Dynamic access port. See the
“Configuring Dynamic Access Ports on VMPS Clients” section
for more information.
–
Secure port. See the
“Configuring Port Security” section on page 21-8
for more information.
–
802.1X authenticated port. See the
“Using 802.1X with Voice VLAN Ports” section on page 9-6
for more information.
–
Protected port. See the
“Configuring Protected Ports” section on page 21-5
for more
information.
Configuring a Port to Connect to a Cisco 7960 IP Phone
Because a Cisco 7960 IP Phone also supports a connection to a PC or other device, a port connecting the
switch to a Cisco 7960 IP Phone can carry mixed traffic.
You can configure the port to carry voice traffic in one of these ways:
•
Configuring Ports to Carry Voice Traffic in 802.1Q Frames, page 14-4
•
Configuring Ports to Carry Voice Traffic in 802.1P Priority-Tagged Frames, page 14-4
You can configure the IP phone to carry data traffic in one of these ways:
•
Overriding the CoS Priority of Incoming Data Frames, page 14-5
•
Configuring the IP Phone to Trust the CoS Priority of Incoming Data Frames, page 14-6