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LLDP frame formats
LLDP sends device information in LLDP frames. LLDP frames are encapsulated in Ethernet II or
Subnetwork Access Protocol (SNAP) frames.
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LLDP frame encapsulated in Ethernet II
Figure 63 Ethernet II-encapsulated LLDP frame
Table 13 Fields in an Ethernet II-encapsulated LLDP frame
Field Description
Destination MAC address
MAC address to which the LLDP frame is advertised. LLDP specifies
different multicast MAC addresses as destination MAC addresses for
LLDP frames destined for agents of different types. This helps
distinguish between LLDP frames sent and received by different agent
types on the same interface. The destination MAC address is fixed to
one of the following multicast MAC addresses:
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0x0180-c200-000E for LLDP frames destined for nearest bridge
agents.
•
0x0180-c200-0000 for LLDP frames destined for nearest customer
bridge agents.
•
0x0180-c200-0003 for LLDP frames destined for nearest
non-TPMR bridge agents.
Source MAC address
MAC address of the sending port.
Type
Ethernet type for the upper-layer protocol. This field 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.
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LLDP frame encapsulated in SNAP