Link Pass Through
This configuration item allows Link Pass Through to be
disabled(2). Link Pass through causes loss of link on one side of a media converter to be passed through to the other side, so that upstream equipment can see fault conditions that would otherwise be hidden by the media converters.
On some models, the Link Pass through logic views receipt of a Far End Fault error pattern as being equivalent to loss of link. The net effect of this is that when either fiber is disconnected, link is dropped on the other side of the converter. Normally, only the disconnection of the Receive fiber would cause this reaction.