[asterisk-users] OT - Integration with building intercom systems

[giovanni.v]

Il 05/07/2012 15.21, Olivier ha scritto:
> Now and then, I'm facing environments in which it could be helpful to
> integrate building intercom systems with Asterisk.

> Is there a standardized protocol available to run  voice, video and
> command on 2-wires and most probably used by  intercom systems ?

I think this is country specific, I know a quite large number of "de 
facto" standards but almost no real standard except the German FTZ 123 D 12.
Most door phone analog system here (Italy) consists of 3/4+1 (bus + 
individual ring signal) wires  and some more recent using proprietary 
digital protocols on a 2 wires bus. Sure I seen something similar in France.

Interfacing any old individual analog door phone to asterisk isn't so 
difficult using a door phone to fxo/fxo adapter like used to do with a 
legacy pbx.

The matter becomes more difficult approaching a building install as 
there are no devices to handle properly that.
I think the snom PA-1 may be a good candidate to play with because of a 
versatile I/O that could be interfaced to a custom "door-phone bridge to 
IP".