METRODATA LTD
FC7000 Media Converter
Installation Guide
76-02-047 Rev A
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6 LINK STATE FORWARDING
The FC7x00 supports Link State Forwarding (LSF) which will propagate an error through
the network such that devices downstream are made aware of link problems and can take
appropriate action.
6.1 LSF for Fibre Fault
When a fibre fault occurs, one or both FC7000 units will declare LOS and also LINK
DOWN for the fibre port. With LSF enabled, the FC7000 will then forward this fault to the
copper port by forcing it to the LINK DOWN state. Additionally, the Fibre Port will start
transmitting a special remote fault pattern (FEFI). In response to the remote fault indication
received on the fibre port, the FC7000 will also force the copper port LINK DOWN.
When the fibre is restored, the FC7000 will detect signal and declare LINK UP and
immediately cease transmission of the remote fault pattern and re-enable the copper port.
The link will then be re-established end to end.
6.2 LSF for Copper Fault
If a cable is removed, or disconnected from the 10/100BaseT copper port on the FC7000
the device will declare LINK DOWN. In response to this fault, the FC7000 will propagate
the fault to the Fibre Port. To force the fibre link down, the FC7000 will turn the fibre
transmitter off. The remote FC7000 will now detect LOS/LINK DOWN and respond with
copper link down and fibre remote fault.
Again, when the copper port is re-connected the end to end link will re-establish.
