HP MSR2000/3000/4000 Router Series Layer 2 - LAN Switching Configuration Guide

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LLDPDU formats
LLDP sends device information in LLDPDUs. LLDPDUs are encapsulated in Ethernet II or SNAP frames.
1. LLDPDU encapsulated in Ethernet II
Figure 21 Ethernet II-encapsulated LLDPDU
Table 7 Fields in an Ethernet II-encapsulated LLDPDU
Field Descri
p
tion
Destination MAC address
MAC address to which the LLDPDU is advertised. To distinguish between LLDP
packets sent and received by different agent types on the same interface, LLDP
specifies different multicast MAC addresses as destination MAC addresses for
LLDP packets to agents of different types. It is fixed to multicast MAC address
0x0180-C200-000E for LLDP packets destined for the nearest bridge
neighbor, 0x0180-C200-0000 for LLDP packets destined for the nearest
customer bridge neighbor, or 0x0180-C200-0003 for LLDP packets destined
for the nearest TPMR bridge neighbor.
Source MAC address MAC address of the sending port.
Type Ethernet type for the upper layer protocol. It is 0x88CC for LLDP.
Data LLDPDU.
FCS
Frame check sequence, a 32-bit CRC value used to determine the validity of
the received Ethernet frame.
2. LLDPDU encapsulated in SNAP
Figure 22 SNAP-encapsulated LLDPDU