This could be implemented through a message and extension ringing system. Depending on the desired degree of privacy a message could say something like,"To ring this phone please enter your privacy code number now." OR alternatively the message could say "To ring this phone please press 364 now."
In the first instance only persons to whom you have provided the PIN could contact you. (This would eliminate all Robo calls, telephone marketers, charities, and political solicitations.
In the second instance it would allow only actual persons who listens to the message to ring through. This wojuld eliminate Robo calls and most other auto dialed calls.
Other features could be message recording etc.
Does anyone know of already available software to do this or are you capable of developing software of this nature. This application would be the best possible solution to maintaining privacy.
Edited by jrmourning, 13 November 2012 - 02:43 PM.