MIM 2016 Phone Gate questions

Hi,

So MIM ships with a Phone Gate, which enables user authentication via telephone call.

Does this mean we have to integrate MIM (write a DLL) with a Phone Provider in the same way as when we integrate FIM with a SMS Gateway (write a DLL)?

Also, what actually happens on this phone call?

• Does someone spell out the OTP?
• Are there only a few Phone providers this works with?
• or does it only tell you "Press the # key now to proceed"?
• or is this Phone Provider an Azure-only service that we have to pay for?

Thank you,

SK