[conspire] anti spam

[Don Marti]

begin Rick Moen quotation of Mon, Mar 21, 2011 at 05:12:57PM -0700:

> Checking these things at SMTP receiving time is _extremely_ effective
> at filtering out spam quickly, with very low load, and with very low
> levels of false positives.  It does the heavy lifting of rejecting a 
> high percentage of obvious spam without the need to spawn high-load 
> external parsers such as SA.

It's friendlier to non-spam senders, too, and makes
it easier to recover from false positives.

If you send legit mail to someone whose server is
set up that way, and the MX rejects your mail based
on one of these spam tests, you know right away when
your own server sends you the bounce -- so you can
try again with a different configuration or a backup
account.  If the mail just goes into a spam box on
the recipient's side you don't get that information.

-- 
Don Marti                    
http://zgp.org/~dmarti/
dmarti at zgp.org