Voice VLAN Configuration

The voice VLAN feature enables switch ports to carry voice traffic with defined settings so that voice and data traffic are separated when coming onto the port. A voice VLAN ensures that the sound quality of an IP phone is safeguarded from deterioration when data traffic on the port is high.

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. A QoS protocol based on the IEEE 802.1P class-of-service (CoS) protocol uses classification and scheduling to send 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 is enabled per-port basis. A port can participate only in one voice VLAN at a time. The Voice VLAN feature is disabled by default. To display the Voice VLAN Configuration page, click System > Voice VLAN > Voice VLAN Configuration.

Voice VLAN Configuration Fields

Field	Description
Voice VLAN Admin Mode	Click Enable or Disable to administratively turn the Voice VLAN feature on or off for all ports.
Interface	Select the interface to configure this service on.
CoS Override Mode	Overrides the 802.1p class-of-service (CoS) value for all data (non-voice) packets arriving at the port. Thus any rogue client that is also connected to the voice VLAN port cannot deteriorate the voice traffic.
Voice VLAN Interface Mode	Select one of the following interface modes: Disable: The voice VLAN service is disabled on this interface. Note that the Admin mode field takes precedence; if a particular interface is enabled, but the Admin Mode field is set to Disabled, the service will not be operational. None: The voice VLAN service is disabled on this interface; however, unlike Disable mode, the CoS override feature is still operational on the port. VLAN ID: The voice VLAN packets are uniquely identified by a number you assign. All voice traffic carries this VLAN ID to distinguish it from other data traffic which is assigned the port’s default VLAN ID. However, voice traffic is not prioritized differently than other traffic. dot1p: This parameter is set by the VoIP device for all voice traffic to distinguish voice data from other traffic. All other traffic is assigned the port’s default VLAN ID. This feature may not be supported by all hardware configurations. Untagged
Operational State	Indicates whether the voice VLAN is operational.

If you make any changes, click Submit to apply the change to the system.
Click Refresh to display the latest information from the router.