Email Authentication

[Phil Mattison]

I've seen a few messages on this board that include 
email addresses with a little note saying that if you
send email to that address you will have to verify 
your own email address before it will be accepted.
I am interested in adding that capability to my own 
email system. I use Linux 7.3 with Postfix. Any
tips on how to do this?

PS- The http://plug.phoenix.az.us/ web site appears to be down.
--
Phil Mattison
Ohmikron Corp.
480-722-9595 ext. 1