Link Layer Discover Protocol (IEEE 802.1ab) Overview
253
•
Port ID TLV
•
Time To Live TLV
•
End Of LLDPDU TLV
The chassis ID and the port ID values are concatenated to form a logical
MSAP identifier that the recipient uses to identify the sending LLDP agent
and port.
A non-zero value in the Time to Live (TTL) field of the TTL TLV indicates to
the receiving LLDP agent how long the LLDPDU information from the MSAP
identifier remains valid. The receiving LLDP agent automatically discards all
LLDPDU information, if the sender fails to update it in a timely manner. A
zero value in TTL field of Time To Live TLV tells the receiving LLDP agent to
discard the information associated with the LLDPDU MSAP identifier.
In addition to the four mandatory TLVs, Release 5.0 software
supports the TLV extension set consisting of Management TLVs and
organizationally-specific TLVs. Organizationally-specific TLVs are defined
by either the professional organizations or the individual vendors that are
involved with the particular functionality being implemented. You can specify
which of these optional TLVs to include in the transmitted LLDPDUs for
each port.
For more information about the supported TLV extension set, see the
following:
•
•
"IEEE 802.1 organizationally-specific TLVs" (page 253)
•
"IEEE 802.3 organizationally-specific TLVs" (page 254)
Management TLVs
The optional management TLVs are as follows:
•
Port Description TLV
•
System Name TLV
•
System Description TLV
•
System Capabilities TLV (indicates both the system supported
capabilities and enabled capabilities, such as end station, bridge, or
router)
•
Management Address TLV
IEEE 802.1 organizationally-specific TLVs
The optional IEEE 802.1 organizationally-specifc TLVs are:
•
Port VLAN ID TLV contains the local port PVID.
Nortel Ethernet Routing Switch 4500 Series
Overview — System Configuration
NN47205-500
02.01
Standard
5.0
23 February 2007
Copyright © 2007, Nortel Networks
Nortel Networks Confidential
.
