Description

EX-series switches accommodate implementation scenarios that include an IP phone and a user’s PC connected to a single switch port.  Typically administrators choose to treat VoIP traffic differently than user data traffic.  In order to do this a mechanism must be able to separate common user data traffic from voice traffic. The voice VLAN is used for this purpose. The voice VLAN enables a single access port to accept untagged, data traffic as well as tagged, voice traffic and associate each type of traffic with distinct and separate VLANs. By doing this, voice traffic can be treated differently, generally with a higher priority than common user data traffic. The following information shows how to configure and monitor Voice VLAN in EX-series switches.

Solution

 The Voice VLAN feature in EX-series switches enables access ports to accept both data (untagged) and voice (tagged) traffic and separate that traffic into different VLANs. 

  • Before configuring Voice VLAN, there are several things to consider:
     
    1. To assign differentiated priority to Voice traffic, it is recommended that class of service (CoS) is configured prior to enabling the voice VLAN feature. Typically, voice traffic is treated with a higher priority than common user traffic. Without differentiated treatment through CoS, all traffic, regardless of the type, is subject to the same delay during times of congestion.
    2. The voice VLAN should only be enabled on access ports on which IP phones are actually connected.
    3. Utilize Link Layer Discovery Protocol Media Endpoint Discovery (LLDP-MED) to provide the voice VLAN ID and 802.1p values to the attached IP phones. This dynamic method associates each IP phone with the appropriate voice VLAN and assigns the necessary 802.1p values, which are used by CoS, to differentiate service for voice traffic within a network.

 

CONFIGURATION FOR VLAN :

[edit vlans]
user@switch# set data-vlan vlan-id <>
user@switch# set voice-vlan vlan-id <>

 

CONFIGURATION FOR VOICE VLAN (NON-ELS) :

In the configuration sample below, we define voice vlan for interface ge-0/0/9 with vlan-name voice-vlan. We have also assigned forwarding class voice. 

[edit ethernet-switching-options]
user@switch# show
voip {
    interface ge-0/0/9 {
        vlan voice-vlan;
        forwarding-class voice;
    }
}

 

CONFIGURATION FOR VOICE VLAN (ELS) :

[edit switch-options]
user@switch# set voip interface ge-0/0/9.0 vlan voice-vlan

 

CONFIGURATION FOR DATA-VLAN :

[edit vlans]
user@switch# set data-vlan switch-options interface ge-0/0/9.0

[edit interfaces]
user@switch# set ge-0/0/9 unit 0 family ethernet-switching vlan members data-vlan
user@switch# set ge-0/0/9 unit 0 family ethernet-switching port-mode  access

 

Please refer below document for more details :

https://www.juniper.net/documentation/us/en/software/junos/user-access/topics/topic-map/802-1x-and-voip-on-switches.html

 

Voice VLAN Monitoring :

To monitor voice VLAN, use the show vlans detail <vlan-name> command. This command shows voice VLAN details such as membership, tag, and state information.

user@switch> show vlans detail voice-vlan
vlan voice:
    Admin state :      Enabled
    Tagging     :      802.1Q Tag 500
    Description :      None
    Primary IP  :      None
    STP         :      None
    Tag         :      ge-0/0/9.0
                       ge-0/0/10.0*
                       ge-0/0/11.0                    * - Active
    Untag       :      None

Modification History

2020-03-04: Article reviewed for accuracy. No changes made. Article is correct and complete

2025-04-10 : Added the configuration for data-vlan

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