Voice Vlan Configuration Guidelines; Configuring A Port To Connect To A Cisco 7960 Ip Phone; Configuring Ports To Carry Voice Traffic In Ieee 802.1Q Frames; Configuring Ports To Carry Voice Traffic In Ieee 802.1P Priority-Tagged Frames - Cisco Catalyst 2950 Software Configuration Manual

Chapter 18 Configuring Voice VLAN

Voice VLAN Configuration Guidelines

These are the voice VLAN configuration guidelines:
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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:
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You can configure the IP phone to carry data traffic in one of these ways:
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You should configure voice VLAN on switch access ports.
The voice VLAN should be present and active on the switch for the IP phone to correctly
communicate on the voice VLAN. Use the show vlan privileged EXEC command to see if the
VLAN is present (listed in the display). If the VLAN is not listed, see
VLANs" for information on how to create the VLAN.
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 plus the maximum number of
secure addresses allowed on the access VLAN. When the port is connected to a Cisco IP phone, the
IP phone requires up to two MAC addresses. The address of the IP phone is learned on the voice
VLAN, and it might or might not be learned on the access VLAN. Connecting a PC to the IP phone
requires additional MAC addresses.
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
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on page 16-28 for more information.
Secure port. See the "Configuring Port Security" section on page 21-6
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IEEE 802.1x authenticated port. See the
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on page 9-8 for more information.
If you enable IEEE 802.1x on an access port on which a voice VLAN is configured and
Note
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
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information.
Configuring Ports to Carry Voice Traffic in IEEE 802.1Q Frames, page 18-4
Configuring Ports to Carry Voice Traffic in IEEE 802.1p Priority-Tagged Frames, page 18-4
Overriding the CoS Priority of Incoming Data Frames, page 18-5
"Configuring Dynamic Access Ports on VMPS Clients" section
"Using IEEE 802.1x with Voice VLAN Ports" section
"Configuring Protected Ports" section on page 21-4
Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
Configuring Voice VLAN
Chapter 16, "Configuring
for more information.
for more
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