Link layer discovery protocol, Setting lldp timing attributes – SMC Networks SMC Tiger 10/100 SMC6128PL2 User Manual

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Link Layer Discovery Protocol

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CLI – This example shows the switch configured with Protocol Group 2 mapped to
VLAN 2.

Link Layer Discovery Protocol

Link Layer Discovery Protocol (LLDP) is used to discover basic information about
neighboring devices on the local broadcast domain. LLDP is a Layer 2 protocol that
uses periodic broadcasts to advertise information about the sending device.
Advertised information is represented in Type Length Value (TLV) format according
to the IEEE 802.1ab standard, and can include details such as device identification,
capabilities and configuration settings. LLDP also defines how to store and maintain
information gathered about the neighboring network nodes it discovers.

Link Layer Discovery Protocol - Media Endpoint Discovery (LLDP-MED) is an
extension of LLDP intended for managing endpoint devices such as Voice over IP
phones and network switches. The LLDP-MED TLVs advertise information such as
network policy, power, inventory, and device location details. The LLDP and
LLDP-MED information can be used by SNMP applications to simplify
troubleshooting, enhance network management, and maintain an accurate network
topology.

Setting LLDP Timing Attributes

Use the LLDP Configuration screen to set attributes for general functions such as
globally enabling LLDP on the switch, setting the message ageout time, and setting
the frequency for broadcasting general advertisements or reports about changes in
the LLDP MIB.

Command Attributes
LLDP – Enables LLDP globally on the switch. (Default: Enabled)
Transmission Interval – Configures the periodic transmit interval for LLDP

advertisements. (Range: 5-32768 seconds; Default: 30 seconds)
This attribute must comply with the following rule:
(transmission-interval * holdtime-multiplier)

65536

Hold Time Multiplier – Configures the time-to-live (TTL) value sent in LLDP

advertisements as shown in the formula below. (Range: 2-10; Default: 4)
The time-to-live tells the receiving LLDP agent how long to retain all information
pertaining to the sending LLDP agent if it does not transmit updates in a timely
manner. TTL in seconds is based on (refresh-interval * holdtime-multiplier)

65536
Therefore, the default TTL is 4*30 = 120 seconds.

Console(config)#protocol-vlan protocol-group 2 vlan 2

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Console(config)#

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