It would be awesome if we could display the callerid information of all incoming telephone calls (from a VoIP provider using SIP protocol) on the top of the TV screen.
It could easily done using some SIP software stack that would display callerid information on the TV screen. It would never answer or make calls.
1- Provide SIP account setup (SIP username, SIP password, SIP proxy,...)
2- Just perform SIP REGISTER and monitor SIP INVITE messages to display callerid information.
All of our current customers are using this callerid feature on their satellite receiver.