Configuring Lldp; Overview; Background; Basic Concepts - H3C SR8800 Configuration Manual

Configuring LLDP

Overview

Background

In a heterogeneous network, it is important that different types of devices from different vendors can
discover one other and exchange configuration for interoperability and management sake. This calls for
a standard configuration exchange platform.
To address this need, the IETF drafted the Link Layer Discovery Protocol (LLDP) in IEEE 802.1AB. The
protocol operates on the data link layer to exchange device information between directly connected
devices. With LLDP, a network device sends local device information (including its major functions,
management IP address, device ID, and port ID) as TLV (type, length, and value) triplets in LLDPDUs to the
directly connected network devices, and at the same time, stores the device information received in
LLDPDUs sent from the LLDP neighbors in a standard management information base (MIB). This allows a
network management system to quickly detect and identify the Layer-2 network topology change.
NOTE:
For more information about MIBs, see

Basic concepts

LLDP frames
LLDP sends device information in LLDP data units (LLDPDUs). LLDPDUs are encapsulated in Ethernet II or
SNAP frames.
Ethernet II-encapsulated LLDP frame format
1.
Figure 52 Ethernet II-encapsulated LLDP frame format
Network Management and Monitoring Configuration Guide
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