There are 2 sets of requirements; for your existing service, and for the iPRIVACY number.
The following 2 requirements for your existing phone service:
1) You need to have the Call Forwarding service active on your existing phone line so you can forward your incoming calls to your IPRIVACY number. Please check with your service provider before ordering this service.
2) You also need the Caller ID service active on the phone number(s) that you will call forward to your iPRIVACY number in order to be able to filter calls using the caller id information.
And since iPRIVACY is a Voice Over Internet (VoIP) service, you will also need:
3) Internet access available at your home or office in order for the iPRIVACY number to work. You can answer calls using your own smartphone (IOS or Android). You may also use any SIP compatible adapter or purchase one from us.