Receiving Fault Notifications
Far-End-Fault(FEF) and Link Pass Through are two troubleshooting features that are often used in conjunction to notify network devices of a loss of link by monitoring the fiber receive(Rx) signal. In the event of a loss of the fiber Rx signal on the far end, the media converter will automatically generate a Far-End-Fault signal and send it on its Tx fiber port to notify the near end converter of a fiber link loss. At which point, Link Pass Through will then disable the copper links on both ends; alerting both end devices of the network failure. The following video illustrates this point nicely:
Stay tuned for the final video in our Advanced Feature Series on Power over Ethernet.