[ILUG] Reminder: Please Respond to S.'s Invitation

[Rick Moen]

Quoting paul at clubi.ie (paul at clubi.ie):

> If SPF isn't to prevent spam, what's the point of it?

To permit MTAs and other software to detect SMTP envelope forgery -- as
stated with abundant clarity, pretty much everywhere covering this topic
(everywhere with technical clue, anyway, i.e., not in the general IT
press).  DKIM, same thing.

> It's also useless at preventing joe-job back-scatter too....

Nothing can _prevent_ joe-job backscatter, unless you can track down the
spam-sending MTAs and pull their mains cords.  However, you can create
the means to detect and reject them.  That's DKIM and SPF.  Well, also
Sender-ID (Microsoft's SPF variant), but that's poisoned by MSFT-owned
patents.

None of these envelope-validating techniques excludes the others.

-- 
Cheers,              Crypto lets someone say "Hi! I absolutely definitely have 
Rick Moen            a name somewhat like the name of a large familiar 
rick at linuxmafia.com  organization, and I'd like to steal your data!" and lots 
McQ!  (4x80)         of users will say "OK, fine, whatever."    -- John Levine