H3C Technologies H3C WX5500E Series Access Controllers - Manual (Page 181)

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Configuring LLDP
This chapter describes how to configure LLDP.
Overview
In a heterogeneous network, a standard configuration exchange platform is required for different types
of network devices from different vendors to discover one another and exchange configuration
information for the sake of interoperability and management.
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 LLDP Data Units (LLDPDUs) to directly connected devices. At the
same time, the device stores the device information received in LLDPDUs sent from the LLDP neighbors in
a standard MIB. LLDP enables a network management system to quickly detect and identify changes to
Layer 2 network topology. For more information about MIBs, see Network Management and Monitoring
Configuration Guide.
Basic concepts
This section describes the basic concepts of LLDP.
LLDPDU formats
LLDP sends device information in LLDPDUs. LLDPDUs are encapsulated in Ethernet II or SNAP frames.
1. Ethernet II-encapsulated LLDPDU
Figure 53 Ethernet II-encapsulated LLDPDU
Table 20 Fields in an Ethernet II-encapsulated LLDPDU
Field Description
Destination MAC
address MAC address to which the LLDPDU is advertised. It is fixed to
0x0180-C200-000E, a multicast MAC address.