“twister” Media Converter 15
Management
Station
Management
Station
Switch/Hub
w/SNMP
Switch/Hub
w/SNMP
“twister”
“twister”
Remote
up to 15km
LED lit = established link
LED unlit = no link
Management
Station
Management
Station
Switch/Hub
w/SNMP
Switch/Hub
w/SNMP
“twister”
“twister”
Broken
Remote
Cable
Trap generated
Trap generated
Link Loss Carried
LED lit = established link
LED unlit = no link
Link Loss Carry Forward (LLCF)
The “twister” has been designed with an LLCF function
for troubleshooting
a remote connection. The unit is shipped with the LLCF disabled.
When LLCF is enabled, the fiber optic ports as well as the twisted-pair ports on
the media converter do not transmit a link signal until they receive a link signal
from the opposite port. For example, if LLCF is enabled and two “twister”
media converters are connected via a fiber cable with nothing else connected to
them, the Link LED does not illuminate. When a valid link is established at the
twisted-pair port, a complete connection is accomplished.
The diagram below shows a typical network configuration using a “twister”
media converter for remote connectivity:
If the fiber connection breaks, or the remote device fails, the “twister”
media converter carries that link loss all the way to the switch/hub which
generates a trap to the management station. The administrator can then
look at the media converter to determine the source of the loss.
IMPORTANT: When connecting a “twister” media converter to a port
that supports auto-negotiation, it is strongly recommended to fix the port
setting to the appropriate speed (100Mbps or 10Mbps) and to either full
or half-duplex. This allows the media converter to sense receive link and
select the active port.
