[LINK] Solution to SPAM checking

[Adam Todd]

I don't know why I haven't thought of this before, years before.  Maybe it 
was spurred by the recent two days of trials where the prosecutor was 
trying to say that on one hand there was something and someone was getting 
something, and on the other and the someone wasn't getting anything.

Anyway, it occurred to me that when an email is sent, .the SMTP server 
connects with the remote server and says "Hello I am me, and I have a 
message for you from XYZ"

What doesn't happen though is the receiving server doesn't say "Just a sec, 
I want to see if you are really who you say you are and you really do 
represent what you claim to represent."

If the RX SMTP server were to check the path of incoming mail or even 
connect to the "reply address" to ensure that it was legitimate and valid 
and was in fact related to the DNS records for the originating domain, then 
SPAM would vanish over night.

You couldn't use a fraud sender address, as the check would show that the 
SMTP server talking and the SMTP server authoritive for the proper sender 
was different.  Even in a relay situation, MX records should generally 
resolve that.

Anyway, just a thought.  It's a "way too big" to solve problem and no one 
really cares enough to stop SPAM being sent, people just want to filter it 
when it's delivered.