i would think, if this system is already biderectional (i.e. cable
modems etc.) that it would be easy.  in fact, you could even use cable
modems to do that, or you could use an unassigned frequency for the
communications.  you might want to do it similarly to how ethernet was
at first implemented with collision detection and such or you might want
to have the central control poll the equipment status at regular
intervals and have the remote equipment respond with it's status when
addressed, thus letting the central control prevent message collisions.
it should be very straight forward on a system that is already
biderectional.  if it isn't already biderectional, i think you'll have
considerable problems.  i'm not familiar with the implementation details
of how a biderectional system sends messages up stream, you might have
to use a cable modem type interface or modify the repeaters.  if you did
use a cable modem type interface, you could assign an ip (preferably in
the ranges reserved for local networks so as no to have to remove them
from the internet ip# pool used by subscribers) to each equipment
monitor, in which case it could either be polled or could send a message
when ever there was a problem, possibly repeating it a few times, or
periodically just to say everything is ok and it's still capable of
messaging.  some system details would definitely help.

Rodrigo Real wrote:
>
> Hi Guys
>
> Does anybody knows if it is possible to communicate at low bandwidth
> through the cableTV?
>
> More specifically, I was thinking about a system which could generate
> alerts when problems were detected on the cable system, such as
> no-break problems. The alerts would be directed to the central
> control, which could call the maintenance people.
>
> Cheers,
> Rodrigo
>
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