•VoiceVLAN ports can also be these port types:
◦Dynamicaccess port.
◦IEEE802.1x authenticatedport.
Ifyou enable IEEE 802.1x on an access port on which a voice VLAN is configured and
towhich a Cisco IP Phone is connected,the phone loses connectivity to the switch for
upto 30 seconds.
Note
◦Protectedport.
◦Asource or destination port for a SPAN or RSPAN session.
◦Secureport.
Whenyou enable port security on an interface that is also configured with a voice VLAN,
youmust set the maximum allowed secure addresses on the port to two plus the maximum
numberof secure addresses allowed on the access VLAN. When the port is connected
toa Cisco IP Phone, the phone requires up to two MAC addresses. The phone address
islearned on the voice VLAN and might also be learned on the access VLAN. Connecting
aPC tothe phonerequires additionalMAC addresses.
Note

Default Voice VLAN Configuration

Thevoice VLAN featureis disabled by default.
Whenthe voice VLAN feature is enabled, all untagged traffic is sent according to the default CoS priority of
theport.
TheCoS value is not trusted for IEEE 802.1p or IEEE 802.1Q tagged traffic.
How to Configure Voice VLAN

Configuring Cisco IP Phone Voice Traffic

Youcan configure a port connected to the Cisco IP Phone to send CDP packets to the phone to configure the
wayin whichthe phone sends voice traffic.The phone can carry voice traffic in IEEE 802.1Q frames for a
specifiedvoice VLAN with a Layer 2 CoS value. It can use IEEE 802.1p priority tagging to give voice traffic
ahigher priority and forward all voice traffic through the native (access) VLAN. The Cisco IP Phone can also
senduntagged 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 2960-XR Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX1
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Configuring Voice VLANs
Default Voice VLAN Configuration