R2511-HP MSR Router Series Layer 2 - LAN Switching Configuration Guide(V5)

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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 37 SNAP-encapsulated LLDPDU
Table 19 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 38.
Figure 38 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: