[e2e] a problem...

[David P. Reed]

If a tree falls in the forest and no one's there to hear it, does it 
make a sound?

Putting a DC bias on the receiver end of a pair ultimately wastes energy 
and reduces receiver S/N, cutting bandwidth achievable, and of course it 
is strictly speaking a reverse channel - so it makes me wonder what 
constraint you are trying to achieve here,and at what cost.

For example - what's wrong with having the connector (fiber) or receiver 
(wireless) have a yellow label that reminds the guy who connects it to 
send an SMS to the guy responsible for the sending end every time the 
link goes up or down?  Knowing what would be wrong with that solution 
might help suggest a good answer.