If all of the POTS attached phones on the "emergency" circuit are on-hook and there are no incoming calls, then not much power should be required. If a phone goes off-hook it should be much easier to detect. If the network facing side is up it can power up the POTS circuit when an incoming call is detected. Carrier detection for ethernet port power sounds reasonable.
For the best of both world, maybe someone needs to build a "black wall phone" that is also the NID and integrates rechargeable D-cells (so flashlight batteries can always be swapped in if the rechargeables are dead). The box would then, of course, know whether it was on or off-hook and could even have a nice display for fiber-carrier status etc... On Fri, Aug 28, 2009 at 3:46 PM, Jay Hennigan <j...@west.net> wrote: > William Herrin wrote: > > You would suggest treating the Ethernet and POTS ports the same for >> power backup purposes until the ethernet port drops its carrier for 60 >> seconds or so? Maybe do the same for the POTs ports wrt detecting >> whether any phones are attached? Nah, that would make far too much >> sense; there must be something fatally wrong with the idea. >> > > Detecting whether an idle phone is attached to a POTS port isn't exactly > trivial. This is more true now with modern phones that don't have > mechanical ringers. > > Keeping the ethernet port up on battery if there is link makes sense. For > that matter a "Wake-on-LAN" style polling to power it for a second every 30 > to detect carrier would be even better. > > -- > Jay Hennigan - CCIE #7880 - Network Engineering - j...@impulse.net > Impulse Internet Service - http://www.impulse.net/ > Your local telephone and internet company - 805 884-6323 - WB6RDV > >
