22 lldp configuration, Overview, Background – H3C Technologies H3C S7500E Series Switches User Manual

Page 311: Basic concepts, Lldpdus, 1 basic concepts, Lldp configuration

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LLDP Configuration

This chapter includes these sections:

Overview

LLDP Configuration Task List

Performing Basic LLDP Configuration

Configuring CDP Compatibility

Configuring LLDP Trapping

Displaying and Maintaining LLDP

LLDP Configuration Examples

Overview

Background

In a heterogeneous network, it is important that different types of network devices from different
vendors can discover one another and exchange configuration for interoperability and management
sake. Therefore, a standard configuration exchange platform was created.

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 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 Link Layer Discovery Protocol Data Units
(LLDPDUs) to the directly connected 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). It allows a network management system to fast detect Layer-2 network topology change and
identify what the change is.

For more information about MIBs, see SNMP Configuration in the Network Management and

Monitoring Configuration Guide

.

Basic Concepts

LLDPDUs

LLDP sends device information in LLDP data units (LLDPDUs). LLDPDUs are encapsulated in
Ethernet II or SubNetwork Access Protocol (SNAP) frames.

1) Ethernet II-encapsulated LLDPDU format

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