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What is FEF and LFP in Media Converter?

What is FEF and LFP in Media Converter?

Ethernet to fiber converters are usually used in pairs so that copper-based networks can communicate in a fiber topology, thus increasing the transmission distance. But, in a media converter network, if the fiber or copper link on one side fails, the device on the other side will continue to work even if no data is transferred and will not report an error to the system administrator. The FEF and LFP functions in Media Converter completely solve this problem.

شبکه مدیا کانورتور

Install media converter


FEF in fiber optic media converter

FEF stands for Far End Fault. It is an IEEE 802.3u compliant protocol for detecting remote data link errors in a network. By using the FEF function in the media converter, it is very easy for the network administrator to diagnose the faults of the fiber media converter links. When a fiber link error is detected, the media converter on this side transmits a long-distance error signal through the fiber link to notify the other media converter at the other end of the error. Then, both copper links connected to the fiber link are automatically disconnected. Using the FEF fiber converter, the fault in the link can be detected and immediately diagnosed, by disconnecting the failed link and sending an end-to-end error to the media converter, preventing data transmission to the failed link.

IF function in media converter

1. If an error occurs at the end of the RX fiber connection, the FEF will detect the error.

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2. Media Converter A then sends a very small error message to Media Converter B to inform it that an error has occurred at the RX end that disables the TX fiber transmission of Converter A.


Media converter troubleshooting


LFP in Media Converter

LFP (Link Fault Pass Through) means that the link fault of the media converter on one side (local side) is passed to the media converter on the other side (remote side). It is used to monitor the copper links connected to the media converters from the local device. When a copper link fails, the media converter passes the failure mode across the entire link and brings down the intermediate fiber link and the copper link at the opposite end. Therefore, the LFP function in the media converter can immediately alert the network administrators of the link problem and provide an efficient network monitoring solution that can minimize the loss caused by the link problem.


If you want to enable FEF and LFP functions on the media converter, be sure to use Ethernet-to-Fiber converters in pairs, and both devices must support FEF and LFP. Also, remember to choose the same make and model for both sides of the connector.