R0106-HP MSR Router Series Layer 2 - LAN Switching Configuration Guide(V7)

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Configuring LLDP
Overview
In a heterogeneous network, a standard configuration exchange platform ensures that different types of
network devices from different vendors can discover one another and exchange configuration.
The Link Layer Discovery Protocol (LLDP) is specified in IEEE 802.1AB. The protocol operates on the data
link layer to exchange device information between directly connected devices. With LLDP, a device sends
local device information as TLV (type, length, and value) triplets in LLDP Data Units (LLDPDUs) to the
directly connected devices. Local device information includes its major functions, management IP
address, device ID, and port ID. The device stores the device information in LLDPDUs from the LLDP
neighbors in a standard MIB. For more information about MIBs, see Network Management and
Monitoring Configuration Guide. LLDP enables a network management system to quickly detect and
identify Layer 2 network topology changes.
Basic concepts
LLDP agent
An LLDP agent is a mapping of an entity where LLDP runs. Multiple LLDP agents can run on the same
interface.
LLDP agents are divided into the following types:
• Nearest bridge agent.
• Nearest customer bridge agent.
• Nearest non-TPMR bridge agent.
A Two-port MAC Relay (TPMR) is a type of bridge that has only two externally-accessible bridge ports,
and supports a subset of the functions of a MAC bridge. A TPMR is transparent to all frame-based
media-independent protocols except for the following:
• Protocols destined to it.
• Protocols destined to reserved MAC addresses that the relay function of the TPMR is defined not to
forward.
LLDP exchanges packets between neighbor agents and creates and maintains neighbor information for
them. Figure 32 sho
ws the neighbor relationships for these LLDP agents. LLDP has two bridge modes:
customer bridge (CB) and service bridge (SB).