Instruction manual

LinkLoss and FiberAlert
The iMcV-Giga-MediaLinX includes such troubleshooting features as FiberAlert
and TX LinkLoss, which can help locate "silent failures" on the network. This
section explains how FiberAlert and LinkLoss work, and how they will react in a
network configuration, which should be understood before attempting
In this section
• About Link Integrity
• What is TX LinkLoss?
• What is FiberAlert?
• Using FiberAlert and LinkLoss
About Link
Integrity
During normal operation, link integrity pulses are transmitted
by all point-to-point Ethernet devices. When an iMcV-Giga-
MediaLinX receives valid link pulses, it knows that the device
to which it is connected is up and sending pulses, and that the
copper or fiber cable coming from that device is intact. The
appropriate “LNK” (link) LED is lit to indicate this.
The iMcV-Giga-MediaLinX also sends out link pulses from its
copper and fiber transmitters, but normally has no way of
knowing whether the cable to the other device is intact and
the link pulses are reaching the other end. The combination of
FiberAlert and LinkLoss allows this information to be obtained,
even when physical access to a remote device (and its link
integrity LED) is not available.
What is TX
LinkLoss?
TX LinkLoss is a troubleshooting feature. When a fault occurs
on the twisted pair segment of a conversion, TX LinkLoss
detects the fault and passes this information to the fiber
segment. If a media converter is not receiving a twisted pair
link, TX LinkLoss disables the transmitter on the media
converter's fiber port. This result is a loss of the link on the
device connected to the fiber port.
Enable TX LinkLoss by setting DIP Switch 5 to the
ON position.
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