Link Layer Discovery Protocol-Media Endpoint Discovery (LLDP-MED) defined in ANSI/TIA-1057, is an extension to the LLDP standard protocol as defined in IEEE 802.1AB. LLDP-MED provides support to deploy Voice over Internet Protocol (VoIP) telephones into the LAN environment. LLDP-MED provides additional TLVs for basic configuration, network policy configuration, location identification, and inventory management.
Following are the types of LLDP-MED devices:
Network connectivity devices: provide access to the IEEE 802 based LAN infrastructure for LLDP-MED endpoint devices. The LLDP-MED Network Connectivity device is a LAN access device based on:
LAN Switch or Router
IEEE 802.1 Bridge
IEEE 802.3 Repeater
IEEE 802.11 Wireless Access Point
Any device that supports the IEEE 802.1AB, LLDP-MED, and can relay IEEE 802 frames.
Endpoint devices: located at the IEEE 802 LAN network edge, participating in the IP communication service using the LLDP-MED framework. The endpoint devices are divided into three classes:
Class 1 - LLDP-MED Generic Endpoint devices, for example, IP communication controllers.
Class 2 - LLDP-MED Media Endpoint devices, for example, media servers, conference bridges.
Class 3 - LLDP-MED Communication Endpoint devices, for example, IP telephones.
The organizational-specific TLVs for use by LLDP-MED network connectivity and endpoint devices are:
Capabilities TLV — enables a network element to determine whether particular connected devices support LLDP-MED, and also discover the TLVs supported by specific network connectivity or endpoint devices.
Network Policy Discovery TLV — enables both network connectivity and endpoint devices to advertise VLAN information, Layer 2, and Layer 3 priorities associated with a specific set of applications on a port. In addition, an LLDP-MED endpoint advertises this TLV for supported application types to enable the discovery of specific policy information and the diagnosis of network policy configuration mismatch issues.
Location Identification Discovery TLV — allows network connectivity devices to advertise the appropriate location information for communication endpoint devices, including emergency call service location, to use in the context of location-based applications.
Extended Power-via-MDI Discovery TLV — enables advanced power management between an LLDP-MED network connectivity and endpoint devices. The Extended Power-via-MDI TLV enables the advertisement of fine grained power requirement details, endpoint power priority, and power status for network connectivity and endpoint devices.
Important
Product notice: This TLV is not applicable on the VSP 8600 Series because Power over Ethernet (PoE) is not supported.
Inventory Management Discovery TLV — enables tracking and identification of inventory-related attributes for endpoint devices. For example, manufacturer, model name, and software version.