IMC Networks iMcV-LIM

FX LinkLoss, TX LinkLoss, Link Fault Pass-Through, Far End Fault and

FiberAlert

iMcV-LIM modules include the troubleshooting features FiberAlert, TXLL, FXLL, FEF

and LFPT that help locate

silent failures

on a network. Before attempting to install the

module(s), understand how these features work and react to a specific network

configuration.

Link Integrity

During normal operation, link integrity pulses are transmitted by all point-to-point

Ethernet devices. When an IMC Networks media converter 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 IMC Networks media converter 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.

FX LinkLoss (FXLL)

FX LinkLoss is a troubleshooting feature. When enabled, if a fault occurs on the fiber

segment of a conversation, FX LinkLoss detects the fault and passes this information to

the twisted pair segment. If a media converter is not receiving a fiber link, FX

LinkLoss disables the transmitter on the media converter’s twisted pair port. This

results in a loss of link on the device connected to the twisted pair port, and the TXLL

LED will blink.

TX LinkLoss (TXLL)

TX LinkLoss is a troubleshooting feature. When enabled, if 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

results in a loss of the link on the device connected to the fiber port, and the FXLL

LED will blink.