Asterisk Clients Encryption

Hi all,

OK. I would like to add an encryption feature for the Asterisk clients.
For example, when user A calls user B, user A knows that his/her call is not spoofed and user A also knows that he/she is calling the “real” user B, not someone else who “pretends” to be B?

I would like to add this feature just to prevent call-spoofing…

Is Asterisk capable doing this?