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5. Link Fault Pass Through (LFP)
The LFP function includes the Link Fault Pass Through
function (LLCF/LLR) and the DIP Switch design. LLCF/LLR can
immediately alarm administrators the problem of the link media
and provide efficient solution to monitor the net. The DIP Switch
provides disable or enable the LFP function.
LLCF (Link Loss Carry Forward) means when a device connected
to the converter and the TP line loss the link, the converter’s
fiber will disconnect the link of transmit. LLR (Link Loss Return)
means when a device connected to the converter and the fiber
line loss the link, the converter’s fiber will disconnect the link
of transmit. Both can immediately alarm administrators the
problem of the link media and provide efficient solution to
monitor the net.
Link Loss Carry Forward (LLCF)
GTP-80X incorporates an LLCF function for troubleshooting a
remote connection. When LFP function is enabled, the FL / TP
ports do not transmit a link signal until they receive a link signal
from the opposite port.
The diagram below shows a typical network configuration with a
good link status using GTP-80X for remote connectivity.
Media
Converter
Management
Station
Switch/Hub
w/SNMP
Management
Station
Media
Converter
Switch/Hub
w/SNMP
TP
TP
Fiber
Cable
LFP ON
LFP ON
l
LED lit = established link
°
LED unlit = no link
Media
Converter
Management
Station
Switch/Hub
w/SNMP
Management
Station
Media
Converter
Switch/Hub
w/SNMP
TP
TP
Broken
Fiber
Cable
LFP ON
LFP ON
l
LED lit = established link
°
LED unlit = no link
