I have an office in building tha have 20 aparments. We have an old analog doorphone system which require each resident to have an analog phone in their room. We like to change our aparment system to IP Doorphone.
I Cant change the system of the all buiding, i only can change my system of my office, but i cant put another keypad on the building door, i need to use the analag keypad whit this cables, and if exist i can put in my office something that convert the analog system to IP system.
We already have an asterisk voip system in our office for telephony.
You would use a VoIP FXS gateway attached to your existing system. Each of your door phones would be given an extension on your existing system and the door phone connected to the gateway.
The Cisco SPA8000 is a good unit. It has 8 FXS ports, so you would need 4 units.
From your description, it llooks like your door/intercom system is a proprietary system unique to the manufacturer. In my opinion there would be little hope to directly interface it to an Asterisk system.
Hi, door phones are quite common to have the 4/5 wire connectino and there is a unit that can interface between this and a VoIP phone system made by a company called Tema in Italy. Look up the Tema AA-10 or AA-11 (depending on whether you want trunk or extension interface), im not sure where to get them from but im sure a quick scan of the web will tell you. The only issue I think you may have though is how to interface with multiple call buttons.
