Configuring Voice VLAN Capability of LLDP

Prerequisites

Before configuring the voice VLAN capability of LLDP on an interface, enable LLDP globally and on the interface.

Context

The voice VLAN capability of LLDP can change the transmission priority of voice data flows to ensure high-quality transmission of voice services.

As shown in Figure 1, a network transmits data flows of various services, including high speed Internet (HSI), voice over IP (VoIP), and Internet protocol television (IPTV). Voice services are sensitive to packet loss and delay. To ensure high-quality voice service, voice data flows need to be transmitted with a high priority through an exclusive path.

Figure 1 Voice VLAN networking

The traditional voice VLAN function allows network administrators to create a voice VLAN and add interfaces with voice devices attached to the voice VLAN. Then voice data flows are transmitted in the voice VLAN. Quality of service (QoS) parameters are configured for the voice data flows to increase their priority and improve the voice service quality. However, configuration of the traditional voice VLAN function is complex. Network administrators want a simpler and easier-to-use method to implement the voice VLAN function.

The device provides an easier method to implement the voice VLAN function: configure the voice VLAN capability of LLDP.

LLDP voice VLAN can only be configured on a physical Ethernet interface working in Layer 2 mode.

Procedure

Configuring the voice VLAN capability of LLDP to interoperate with LLDP-capable voice devices
1. Run system-view
  
  The system view is displayed.
2. Run interface interface-type interface-number
  
  The interface view is displayed.
3. Run lldp tlv-enable med-tlv network-policy voice-vlan vlan vlan-id [ cos cvalue | dscp dvalue ]^*
  
  The voice VLAN capability of LLDP is configured on the interface.
  
  If only the VLAN ID of the voice VLAN is configured, the cos and dscp use their default values, which are 5 and 46 respectively.
Configuring the voice VLAN capability of LLDP to interoperate with CDP-capable voice devices
1. Run system-view
  
  The system view is displayed.
2. Run interface interface-type interface-number
  
  The interface view is displayed.
3. Run lldp tlv-enable med-tlv network-policy voice-vlan vlan vlan-id [ cos cvalue | dscp dvalue ]^*
  
  The voice VLAN capability of LLDP is configured on the interface.
  
  If only the VLAN ID of the voice VLAN is configured, the cos and dscp use their default values, which are 5 and 46 respectively.
4. Run lldp compliance cdp txrx
  
  The interface is enabled to exchange information with CDP-capable devices.

Checking the Configuration

Run the display lldp local [ interface interface-type interface-number ] command to check the LLDP status of all interfaces or a specified interface.