HP 6600 Configuration Manual page 216

Field
FCS
2. LLDPDU encapsulated in SNAP
Figure 74 LLDPDU encapsulated in SNAP
Table 21 Fields in a SNAP-encapsulated LLDPDU
Field
Destination MAC address
Source MAC address
Type
Data
FCS
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 75 LLDPDU encapsulation 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:
Description
Frame check sequence, a 32-bit CRC value used to determine the validity of
the received Ethernet frame.
Description
MAC address to which the LLDPDU is advertised. It is fixed at
0x0180-C200-000E, a multicast MAC address.
MAC address of the sending port.
SNAP type for the upper layer protocol. It is 0xAAAA-0300-0000-88CC for
LLDP.
LLDPDU.
Frame check sequence, a 32-bit CRC value used to determine the validity of
the received Ethernet frame.
Figure
207
75.