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Chapter 19 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.
• 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 port security on a per-VLAN basis.
• 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
on page 17-28 for more information.
–
Secure port. See the “Configuring Port Security” section on page 22-7 for more information.
–
802.1x authenticated port. See the “Using 802.1x with Voice VLAN Ports” section on page 10-7
for more information.
Note If you enable 802.1x on an access port on which a voice VLAN is configured and to
which a Cisco IP Phone is connected, the Cisco IP Phone loses connectivity to the
switch for up to 30 seconds.
–
Protected port. See the “Configuring Protected Ports” section on page 22-4 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 19-4
• Configuring Ports to Carry Voice Traffic in 802.1p Priority-Tagged Frames, page 19-4
You can configure the IP phone to carry data traffic in one of these ways:
• Overriding the CoS Priority of Incoming Data Frames, page 19-5
• Configuring the IP Phone to Trust the CoS Priority of Incoming Data Frames, page 19-6