IMC Networks MediaConverter/1 Operation Manual page 12

What is Pulsing FiberAlert?
Pulsing FiberAlert minimizes the problems associated with the loss of one strand of
fiber. If a strand is unavailable, the IMC Networks device at the receiver end notes
the loss of link. The device will stop transmitting data and start sending link pulses.
Until a valid link is received, the fiber link LED will be OFF on the device on the
receiver side of the fiber strand with the fault while the fiber Link LED on the other
unit will blink. Pulsing FiberAlert notifies a local site administrator of a fault, allowing
quick determination of where a cable fault resides.
Note
You can enable Pulsing FiberAlert on BOTH sides of a conversion.
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