User Manual

10
4. Link Fault Passthrough (LFP)
The LFP function includes the Link Fault Passthrough function
(LLCF/LLR) and the DIP switch design. LLCF/LLR can
immediately alert administrators to the problem of the link
media and provide an efcient solution to monitoring the net.
The DIP switch’s LFP function can be disabled or enabled.
LLCF (Link Loss Carry Forward) means when a device is
connected to the converter and the TP line loses the link, the
converter’s ber will disconnect the transmission link. LLR
(Link Loss Return) means when a device is connected to the
converter and the ber line loses the link, the converter’s ber
will disconnect the transmission link. Both can immediately alert
administrators to the problem of the link media and provide an
efcient solution to monitoring the net.
Link Loss Carry Forward (LLCF)
The GTP-805A incorporates an LLCF function for troubleshooting
a remote connection. When LFP function is enabled, the FL and
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 GTP-805A 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