The following table shows the details about the currently defined TLVs.
TLV type TLV Name Description Usage in
LLDPDU
0 End of LLDPDU
Mark the end of the TLV sequence in LLDPDUs.
Any information following an End Of LLDPDU
TLV shall be ignored.
Mandatory
1 Chassis ID Identifies the Chassis
address of the connected
device.
Mandatory
2 Port ID
Identifies the specific port that transmitted the
LLDP frame. When the device does not advertise
MED TLV, this field displays the port name of the
port; when the device advertises MED TLV, this
field displays the MAC address of the port.
Mandatory
3 Time To Live
Indicates the number of seconds that the
neighbor device is to regard the local information
to be valid.
Mandatory
4 Port Description Identifies the description string of the port. Optional
5 System Name Identifies the system name. Optional
6 System
Description
Identifies the system description. Optional
7 System
Capabilities
Identifies the main functions of the system and
the functions enabled.
Optional
8 Management
Address
I
dentifies the management IP address, the
corresponding interface number and OID (Object
Identifier). The management IP address is
specified by the user.
Optional
127 Organizationally
Specific
Allows different organizations, such as IEEE
802.1, IEEE 802.3
, IETF, as well as individual
software and equipment vendors, to define TLVs
that advertise information to remote device.
Optional
Optional TLVs are grouped into two categories including basic management TLV and
Organizationally-specific TLV.
1) Basic Management TLV
A set of TLVs considered to be basic to the management of the network stations are required for
all LLDP implementations.
2) Organizationally Specific TLV
Different organizations have defined various TLVs. For instance, Port VLAN ID TLV, Port and
Protocol VLAN ID TLV, VLAN Name TLV And Protocol Identity TLV are defined by IEEE 802.1,
while MAC/PHY Configuration/Status TLV, Power Via MDI TLV, Link Aggregation TLV and
Maximum Frame TLV are defined by IEEE 802.3. Some specific TLVs are for LLDP-MED protocol,
such as LLDP-MED Capabilities TLV, Network Policy TLV, Extended Power-via-MDI TLV,
Hardware Revision TLV and so on.
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