I have developed a caller Id detector for FXO to decode the caller ID coming on the PSTN line.
I have a confusion about Type 2 caller ID usage in FXO. Suppose the PSTN line connected to FXO is being used by one VoIP user (FXS). If another PSTN user calls the same PSTN line connected to the FXO. The PSTN exchange plays call waiting tone to the FXO.
1. Is it required to transmit this call waiting tone to the VoIP user (FXS).
2. If the VoIP Gateway detects the Call waiting caller ID. Is it required to send this caller ID to the VoIP user.
3. If the PSTN user on call w aiting want to call to another voip user using the same VoIP gateway which has only one FXO port (which is already in use), what will be the solution. In this case we should not display the call waiting to the current voip user, right?.
Many of your questions have no firm requirement. It may be up to the individual country requirements and the type of service that you will provide.
1. If you do not transmit this tone to the FXS, then how will the FXS user know there is another incoming call and switch to it? In many countries, like the US, you pay extra for the call waiting feature, but if you do not transmit this through, then you are basically denying the user of a feature they paid for.
2. Again, this may be a feature that the user paid for on the PSTN line and you should send this through.
3. You stated that a “PSTN user” wants to call another voip user, but keep in mind call waiting is for the FXS user, not FXO user.