Configuring A Port Connected To A Cisco 7960 Ip Phone; Configuring Ip Phone Voice Traffic; Configuring The Priority Of Incoming Data Frames - Cisco WS-C3750-48PS-S Software Configuration Manual

Configuring Voice VLAN
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Configuring a Port Connected 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 IP Phone can carry mixed traffic. You can configure a port to decide how the IP phone
carries voice traffic and data traffic.
This section includes these topics:
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Configuring IP Phone Voice Traffic

You can configure a port connected to the Cisco IP Phone to send CDP packets to the phone to configure
the way in which the phone sends voice traffic. The phone can carry voice traffic in 802.1Q frames for
a specified voice VLAN with a Layer 2 CoS value. It can use 802.1p priority tagging to give voice traffic
a higher priority and forward all voice traffic through the native (access) VLAN. The IP phone can also
send untagged voice traffic or use its own configuration to send voice traffic in the access VLAN. In all
configurations, the voice traffic carries a Layer 3 IP precedence value (the default is 5).
Catalyst 3750 Switch Software Configuration Guide
16-4
The Cisco IP Phone and a device attached to the phone cannot communicate if they are in the same
VLAN and subnet but use different frame types because traffic in the same subnet is not routed
(routing would eliminate the frame type difference).
You cannot configure static secure MAC addresses in the voice VLAN.
Voice VLAN ports can also be these port types:
Dynamic access port. See the
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on page 13-30 for more information.
802.1x authenticated port. See the
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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
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information.
A source or destination port for a SPAN or RSPAN session.
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Secure port. See the "Configuring Port Security" section on page 24-7
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Note 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 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 IP
phone address is learned on the voice VLAN and might also be learned on the access
VLAN. Connecting a PC to the IP phone requires additional MAC addresses.
Configuring IP Phone Voice Traffic, page 16-4
Configuring the Priority of Incoming Data Frames, page 16-6
"Configuring Dynamic-Access Ports on VMPS Clients" section
"Configuring 802.1x Authentication" section on page 10-13
"Configuring Protected Ports" section on page 24-5
Chapter 16 Configuring Voice VLAN
for more
for more information.
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