Phoenix Contact FL NAT SMN 8TX, Руководство пользователя, Страница: 95 / 102

LLDP (Link Layer Discovery Protocol)
7966_en_04 PHOENIX CONTACT
7-1
7 LLDP (Link Layer Discovery Protocol)
7.1 Basics
LLDP The switch supports LLDP according to IEEE 802.1ab and enables topology detection of
devices that also have LLDP activated.
Advantages of using LLDP:
– Improved error location detection.
– Improved device replacement.
– More efficient network configuration.
The following information is received by neighbors or transmitted to neighbors, as long as
LLDP is activated:
– The device transmits its own management and connection information to neighboring
devices.
– The device receives management and connection information from neighboring devic-
es.
Displaying LLDP
information
The information that is collected is presented in a table in WBM. The table includes the port
numbers that are used to connect both devices together, as well as the IP address, the
device name of neighboring devices, and the device type.
LLDP General The Link Layer Discovery Protocol (LLDP) according to 802.1ab is used by network devices
to learn and maintain the individual neighbor relationships.
Function
A network infrastructure component transmits a port-specific BPDU (Bridge Protocol Data
Unit), which contains the individual device information, at the “Message Transmit Interval”
to each port in order to distribute topology information. The partner connected to the
relevant port learns the corresponding port-specific neighbors from these BPDUs.
The information learned from the BPDUs is saved for a defined period of time as the TTL
value (TTL - Time To Live). Subsequent receipt of the same BPDUs increases the TTL value
again and the information is still saved. If the TTL elapses, the neighbor information is
deleted.
Please note that a blocking port using RSTP does not receive LLDP BPDUs, but does
send them.
An FL NAT SMN 8TX(-M) manages a maximum of 50 items of neighbor information, all
other information is ignored.
If several neighbors are displayed on one switch port, then there must be at least one
other switch/hub, which does not support or has not activated LLDP, installed between
this switch and the neighbor indicated.