R3303-HP HSR6800 Routers Layer 2 - LAN Switching Configuration Guide

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Field Descri
p
tion
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 75 LLDPDU encapsulated in SNAP
Table 21 Fields in a SNAP-encapsulated LLDPDU
Field Descri
p
tion
Destination MAC address
MAC address to which the LLDPDU is advertised. It is fixed at
0x0180-C200-000E, a multicast MAC address.
Source MAC address MAC address of the sending port.
Type
SNAP type for the upper layer protocol. It is 0xAAAA-0300-0000-88CC for
LLDP.
Data LLDPDU.
FCS
Frame check sequence, a 32-bit CRC value used to determine the validity of
the received Ethernet frame.
LLDPDUs
LLDP uses LLDPDUs to exchange information. An LLDPDU comprises multiple TLV sequences. Each TLV
carries a type of device information, as shown in Figure 76.
Figure 76 LLDPDU enca
psulation format
An LLDPDU can carry up to 28 types of TLVs. Mandatory TLVs include Chassis ID TLV, Port ID TLV, Time
to Live TLV, and End of LLDPDU TLV. Other TLVs are optional.
TLVs
TLVs are type, length, and value sequences that carry information elements. The type field identifies the
type of information, the length field measures the length of the information field in octets, and the value
field contains the information itself.
LLDPDU TLVs include the following categories: