Specifications

LLDP and LLDP-MED Configuration Examples
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LLDP, LLDP-MED Overview
LLDP (Link Layer Discovery Protocol – IEEE 802.1AB) provides a standards-based Layer 2
protocol for enabling network switches to advertise themselves and learn about adjacent
connected LLDP devices. LLDP-MED (LLDP Media specific – ANSI/TIA-1057) is an extension
to LLDP to provide auto-configuration and exchange of media related information, such as
Voice VLAN and QoS, and is designed to provide enhanced VoIP deployment and management.
Typically phones will need information such as QoS settings and also location information.
Since these network settings are specific to a location, or connection point, then having the
IP-Phone auto discover this information from the local Ethernet switch reduces setup within
other areas of the network, e.g. DHCP, and eases Moves, Adds and Changes of devices.
The following example describes how to set up LLDP/LLDP-MED for an access port on a
ProCurve Networking 5300xl Ethernet switch. Commands may differ depending upon
manufacturer and model. (LLDP instructions for the ProCurve 2600, 3500, 5300 and 5400
model switches are the same.) Instructions in the sections below only contain a subset of CLI
commands available. Please read the device documentation to determine the correct instruction
set to use.
Configuration Overview
A number of parameters within the Layer 2 access switch need to be configured in order to
advertise the correct LLDP/LLDP-MED information to the end devices.
LLDP-MED includes information regarding the voice VLAN ID, DSCP and Priority and supports
both tagged and untagged voice devices. However, since Untagged voice devices do not include
the VLAN header or L2 Priority information, the Switch Access Port parameters will need to
reflect this and apply policy changes at the ingress port. This is described further in “Connecting
non-VLAN enabled voice devices to the network” on page 325.
By default, LLDP and LLDP-MED are enabled, and default Priority and DSCP values are already
defined for voice services. All that is required is to identify the voice VLAN with "voice" service
and assign the voice VLAN to the required ports.
LLDP-MED advertising information determination
LLDP-MED has the capability to provide the following information to the voice devices
connected to the network switch:
•VLAN ID
•Priority
•DSCP
Note: For additional clarity, the user input is shown in bold font within this appendix.