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is exchanged between directly connected devices. Information in LLDP PDUs
received is restored in its MIB. A LLDP-enabled device operating in the TxRx
mode or Tx mode sends LLDP PDUs to its directly connected devices
periodically. It also sends LLDP PDUs when the local configuration changes to
inform the neighboring devices of the change timely. In any of the two cases,
an interval exists between two successive operations of sending LLDP PDUs.
This prevents the network from being overwhelmed by LLDP PDUs even if the
LLDP operating mode changes frequently. To enable the neighboring devices
to be informed of the existence of a device or an LLDP operating mode change
(from the disable mode to TxRx mode, or from the Rx mode to Tx mode) timely,
a device can invoke the fast sending mechanism. In this case, the interval to
send LLDP PDUs changes to one second. After the device sends specific
number of LLDP PDUs, the interval restores to the normal. An LLDP-enabled
device operating in the TxRx mode or Rx mode validates the TLVs carried in
the LLDP PDUs which receive and store the valid neighboring information. An
LLDP PDU also carries a TTL (time to live) setting with it. The information
about a neighboring device maintained locally ages out when the
corresponding TTL expires.
LLDP Status:
Enable/Disable LLDP.
LLDP hello time:
LLDP hello time value which is time interval between the
transmission LLDP info packets. Value range is from 5 to 32768. Default value
is 30.
LLDP hold time:
LLDP hold time value. Value range is from 2 to 10. Default
value is 4.
