Door Entry Forward call from door bell station to IP Phone?

[teukuridho]

Hi

I'm planning to get a hikvision indoor station and a door phone station. I don't have any experiences with them but I think I know their basic functionally.

My client needs when a call button is pressed on the door phone station, it will call the indoor station, but if the indoor station doesn't answer in 3 minutes, the call will be forwarded to IP Phone of Asterisk/any IP PABX, is this possible to do and has anyone done this before?

Also does Hikvision provide API/SDK to interact with the station, like to unlock locks, get video and audio stream etc..

Thanks