User Manual

10
4. 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 alert administrators about problems with the link
media and provide an efcient solution to monitor the net. The
DIP Switch can disable or enable the LFP function.
With LLCF (Link Loss Carry Forward), when a device connected
to the converter loses the TP line link, the converter’s ber will
disconnect the link of transmit. With LLR (Link Loss Return),
when a device connected to the converter and loses the ber
line link, the converter’s ber will disconnect the link of transmit.
Both can immediately alert administrators about link media
problems and provide an efcient solution to monitor the net.
Link Loss Carry Forward (LLCF)
The FCU-1802Px 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 conguration with a
good link status using the FCU-1802Px for remote connectivity.
Media
Converter
Management
Station
Switch/Hub
w/SNMP
Management
Station
Media
Converter
Switch/Hub
w/SNMP
TP TP
Fiber
Cable
LFP ONLFP ON
l LED lit = established link ° LED unlit = no link
If the connection breaks, the FCU-1802Px link loss forwards
to the switch/hub that generates a trap to the management