Summary of ANTI-spam techniques now available

Jon Lewis jlewis at
Tue Aug 5 04:29:44 UTC 1997

On Mon, 4 Aug 1997, Dana Hudes wrote:

> So go ahead, Ehud, I dare you to block all PSI in 38/8 and the
> UUNET dial ports as well.
Why do dialup ports need to talk directly to your mail servers?
Few dialup users use software that handles SMTP delivery...they generally
do the equivalent of smart host everything off to the provider's SMTP
server, and let it handle sending the message to the actual destination.
I know there are smart mail clients that do handle it themselves...but
they can typically fall-back to the smart host.

I've had the following (plus a few other blocks...cyberpromo, quantcom) 
! dialups bite me
access-list 102 deny tcp eq 25

This was from before I got heavy into check_* rules, so I can probably
remove it now, and ban them in other ways.

 Jon Lewis <jlewis at>  |  Unsolicited commercial e-mail will
 Network Administrator       |  be proof-read for $199/message.
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