Description:

This document describes the configuration steps required on a LANCOM managed switch of the GS-23xx series in order to configure a Voice VLAN. If a VoIP telephone is connected to the switch, the switch recognizes the telephone using the manufacturer ID (OUI address) and activates the Voice VLAN on the switch port. As the Voice VLAN is tagged on this port (tagging mode Hybrid), tagging has to be also activated on the VoIP telephone. It is also possible to connect additional network devices to this port, which are to communicate in another VLAN. For this purpose there is a separate port on many VoIP telephones a PC can be connected to for example. This can save an additional switch.

An OUI address (Organizationally Unique Identifier) consists of the first 24 bits of a MAC address. This is the manufacturer ID assigned by the IEEE. For LANCOM devices the OUI 00 is 00:A0:57.



Requirements:
  • LANCOM switch of the GS-23xx series with current LCOS SX version (download latest version)
  • Any web browser for accessing the webinterface
  • The VoIP telephone has to be configured to tag packets with the Voice VLAN ID (active tagging) 



Scenario:
  • In this example, the voice VLAN has the ID 80.
  • The Voice VLAN is activated on the switch port automatically, when a VoIP telephone is connected and recognized by the OUI.



Procedure:
1. Navigate to the menu Configuration → VLAN → Membership.
  • Add the VLAN 80 and assign a descriptive name.
  • For Port Members choose the designated router port.
2. Navigate to the menu Configuration Voice VLAN → OUI and add the OUI of your SIP telephone if necessary.
3. Switch to the menu Configuration → Voice VLAN → Configuration.
  • Activate the Voice VLAN by setting the Mode to Enabled.
  • Add the VLAN-ID 80.
  • For the designated router port assign the Mode Forced. As Discovery Protocol assign OUI in the dropdown menu.
  • Assign the Mode Auto to all ports where SIP telephones shall be connected and assign the Discovery Protocol OUI.

With the mode "Auto" the MAC addresses of connected network devices are learned statically for a port. The mode "Auto" may therefore only be used for a port, a VoIP telephone is directly connected to. If an access point is connected to a port with this mode, this can cause roaming problems, among other things!

If no VoIP telephone is connected to a port, the mode "Disabled" should be used. If a VoIP telephone is connected indirectly to a port (e.g. via an access point), the mode "Forced" has to be used. With the mode "Forced" the MAC addresses of network participants are learned dynamically.

4. Navigate to the menu Maintenance → Save/Restore → Save Start und save the configuration as Start Configuration.

The Start Configuration is saved boot persistent in the device. Thus the configuration is also available after a reboot or a power outage.

5. To check the function switch to the menu Configuration → VLAN → Switch Status.

 

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