HPE FlexNetwork 5130 HI SERIES, Руководство по настройке

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Table 18 Fields in a SNAP-encapsulated LLDP frame
Field Description
Destination MAC address
MAC address to which the LLDP frame is advertised. It is the same as that
for Ethernet II-encapsulated LLDP frames.
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. An LLDP frame contains only one 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 TLVs. Each TLV
carries a type of device information, as shown in
Figure 57 .
Figure 71 LLDPDU encapsulation format
An LLDPDU can carry up to 32 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
A TLV is an information element that contains the type, length, and value fields.
LLDPDU TLVs include the following categories:
•
Basic management TLVs
•
Organizationally (IEEE 802.1 and IEEE 802.3) specific TLVs
•
LLDP-MED (media endpoint discovery) TLVs
Basic management TLVs are essential to device management.
Organizationally specific TLVs and LLDP-MED TLVs are used for enhanced device management.
They are defined by standardization or other organizations and are optional for LLDPDUs.
•
Basic management TLVs
Table 19 lists the basic management TLV types. Some of them are mandatory for LLDPDUs.
Table 19 Basic management TLVs
Type Description Remarks
Chassis ID Specifies the bridge MAC address of the sending device.
Mandatory.
Port ID
Specifies the ID of the sending port:
•
If the LLDPDU carries LLDP-MED TLVs, the port ID TLV
carries the MAC address of the sending port.
•
Otherwise, the port ID TLV carries the port name.
Time to Live
Specifies the life of the transmitted information on the receiving
device.
End of LLDPDU Marks the end of the TLV sequence in the LLDPDU.
Port Description Specifies the description for the sending port.
Optional.
System Name Specifies the assigned name of the sending device.