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Voice VLAN

You can configure the switch's ports to carry Voice over IP (VoIP) traffic from IP phones on a specific VLAN. On the Voice VLAN tab, you can apply QoS to VoIP traffic, ensuring call quality even in congested networks.

Global settings

On the Global settings tab, you can configure the following voice VLAN settings:

  • Voice VLAN status: Select one of the following options:

    • Disabled: Turn off voice VLAN.
    • Auto: Automatically detect VoIP devices and assign them to the voice VLAN.
    • OUI: Identify voice devices by Organizationally Unique Identifier (OUI) and assign them to the voice VLAN. See OUI Settings.

  • Voice VLAN ID: Select the voice VLAN ID for the network. Switches only support one voice VLAN.

  • VLAN priority tag: Defines a service priority for traffic on the voice VLAN. The switch uses this value to set the priority of any received VoIP packets when the voice VLAN feature is active on a port.
  • DSCP: Sets the Differentiated Services Code Point (DSCP). This is a value between 0 and 63 that marks packets for QoS. See Differentiated services.
  • 802.1p CoS status: Turn this option on to mark the outgoing voice traffic with the selected CoS priority value.

  • CoS priority: Sets the 802.1p priority tag for voice VLAN traffic. The priority values and the traffic typically associated with them are as follows:

    • 7: Network control (highest)
    • 6: Voice and video signaling
    • 5: Voice media traffic. This is the most common priority setting for voice traffic.
    • 4: Video media
    • 3: Critical applications
    • 2: High-priority data
    • 1: Medium-priority data
    • 0: Best effort (lowest)

  • Aging time: Controls how long the switch waits before removing an automatically assigned port from the voice VLAN after voice traffic stops. When voice traffic stops and the MAC address of the voice device expires, the voice VLAN aging time begins. The switch removes the port from the voice VLAN after the aging time expires. If voice traffic resumes during the aging time, it resets. Set a value between 30 and 1440 minutes. The default is 600.

Click Apply to save your changes.

OUI Settings

When you set Voice VLAN status to OUI, the switch determines whether a received packet is a voice packet by checking its source MAC address. VoIP traffic has a pre-configured Organizationally Unique Identifier (OUI) prefix in the source MAC address. You can manually add specific manufacturers' MAC addresses and descriptions to the OUI table. The switch forwards all traffic received on the voice VLAN ports from a specific IP phone with a listed OUI to the voice VLAN.

You can see the following information about the OUIs configured on the switch:

  • Index: The VoIP sequence ID
  • OUI address: The globally unique ID assigned to a vendor by the IEEE to identify VoIP equipment
  • Description: The vendor of the VoIP equipment.

To add a new OUI entry, click Add, configure the OUI settings, and click Apply.

To update an OUI entry's settings, click Edit. specific entry.

To delete OUI entries, select the entries you want to remove and click Delete.

Port settings

Enhance your VoIP service further by configuring ports to carry IP voice traffic from IP phones on a specific VLAN. Voice VLAN provides QoS for VoIP, ensuring that voice traffic quality doesn't degrade when traffic is received unevenly.

  • Port: Shows the port to which the voice VLAN settings apply and whether the voice VLAN is turned on or turned off for the specified port.

  • CoS mode: Shows the method for assigning CoS priority to voice VLAN traffic as one of the following options:

    • Src: The switch applies source QoS attributes to packets with OUIs in the source MAC address.
    • All: The switch applies all QoS attributes to traffic assigned to the Voice VLAN.

  • Operation status: Shows the operating status for the voice VLAN on the specified port.

To change port settings, select the ports whose settings you want to change and click Edit.