This section describes the commands you use for Voice VLAN. Voice VLAN enables switch ports to carry voice traffic with defined priority so as to enable separation of voice and data traffic coming onto the port. The benefits of using Voice VLAN is to ensure that the sound quality of an IP phone could be safeguarded from deteriorating when the data traffic on the port is high.
Also the inherent isolation provided by VLANs ensures that inter-VLAN traffic is under management control and that network- attached clients cannot initiate a direct attack on voice components. QoS-based on IEEE 802.1P class of service (CoS) uses classification and scheduling to sent network traffic from the switch in a predictable manner. The system uses the source MAC of the traffic traveling through the port to identify the IP phone data flow.
voice vlan (Global Config)
Use this command to enable the Voice VLAN capability on the switch.
Default: disabled
Format: voice vlan
Mode: Global Config
no voice vlan (Global Config)
Use this command to disable the Voice VLAN capability on the switch.
Format: no voice vlan
Mode: Global Config
voice vlan (Interface Config)
Use this command to enable the Voice VLAN capability on the interface or range of interfaces.
You can configure Voice VLAN in one of four different ways:
vlan-id: Configure the IP phone to forward all voice traffic through the specified VLAN. Valid VLAN ID’s are from 1 to 4093 (the max supported by the platform).
dot1p: Configure the IP phone to use 802.1p priority tagging for voice traffic and to use the default native VLAN (VLAN 0) to carry all traffic. Valid priority range is 0 to 7.
none: Allow the IP phone to use its own configuration to send untagged voice traffic.
untagged: Configure the phone to send untagged voice traffic.
no voice vlan (Interface Config)
Use this command to disable the Voice VLAN capability on the interface.
Format: no voice vlan
Mode: Interface Config
voice vlan data priority
Use this command to either trust or untrust the data traffic arriving on the Voice VLAN interface or range of interfaces being configured.
Default: trust
Format: voice vlan data priority {untrust | trust}
Mode: Interface Config
show voice vlan
Format: show voice vlan [interface {<unit/slot/port>| all}]
Mode: Privileged EXEC
When the interface parameter is not specified, only the global mode of the Voice VLAN is displayed.
Administrative Mode: The Global Voice VLAN mode.
When the interface is specified:
Voice VLAN Mode: The admin mode of the Voice VLAN on the interface.
Voice VLAN ID:The Voice VLAN ID
Voice VLAN Priority: The do1p priority for the Voice VLAN on the port.
Voice VLAN Untagged: The tagging option for the Voice VLAN traffic.
Voice VLAN CoS Override: The Override option for the voice traffic arriving on the port.
Voice VLAN Status: The operational status of Voice VLAN on the port.
