Perle PoE/PoE+ 10/100/1000 Ethernet Media Converter
Installation Guide
11
If the installation has a media converter on both ends of the fiber link and both are
set-up for Smart Link Pass-Through, then a loss of copper link on the far end
device will propagate through both media converters and will result in a loss of link
at the near end device.
Fiber Fault Alert (Switch 3)
Switch Position
Fiber Port 1 Fiber Port 2
Up (default)
Enabled
Enabled
Down
Disabled
Enabled
Enabled: If the media converter detects a loss of signal on the fiber receiver, it will
immediately disable its fiber transmitter signal on the same port. This, in effect,
notifies the fiber link partner that an error condition exists on the fiber connection.
If the remote media converter is set up for Fiber Fault Alert (FFA) and the local
media converter is set up with Link Pass-Through, a loss of fiber link on either the
transmit or receive line will be passed through to the local copper connection thus
notifying the connected device.
If the media converter has been set to Smart Link Pass-Through mode, the effect
will be the same as FFA, since the link loss on the fiber receiver will result in
bringing down the copper link, which will in turn cause the transmit fiber link to be
brought down.
Note: This feature only takes effect if Fiber Negotiation has been
turned off.
Disabled: The media converter will not monitor for or generate Fiber Fault Alert.
Illustration of the FFA
The following diagram is an illustration of the operation of this feature.
(A) – Remote Media Converter setup for Fiber Fault Alert Enabled, Fiber
Negotiation – OFF and Link Mode – Standard.
(B) – Local Media Converter setup for Fiber Fault Alert Enabled, Smart Link Pass-
Through On and Fiber Negotiation - OFF
1 – (A) Loses fiber connection on its receiver.
2 – (A) Sends FFA.
3 – (B) Detects FFA signal and shuts down the fiber link.
4 – (B) Drops link on copper connection because Smart Link Pass-Through is
configured.
5 – (A) Link on copper connection is not affected because Smart Link Mode is set
to Standard.
