That's greylisting and I've decided against it because it penalizes the
god senders. However - I did a vaiation of that I call penalty boxing
where after a spam or something suspicious I might return a defer to
subsequent emails for a 5 minute period to discourage further spamming.
Ron McKeating wrote:
>Hi all, we recently had a presentation from Mirapoint on how, if we
>payed them oodles of dosh, they could install some really expensive
>boxes and sell us some really expensive software to do exactly what we
>do with exim, spamassassin and clamav. One of the things that I did find
>interesting (or even scary) was their explanation of how something they
>call mail-hurdle works as a spam filter. Basically it is this.
>
>When an MTA tries to deliver an email, the sender (they were not sure if
>it was the actual sender email address or the sending server helo) is
>looked up in a database, if they are valid senders then the email is
>accepted. If they are not in the database, then the message is given a
>defer, the sender is then written into the database. The idea is when
>they retry they will be in the database as so they accept the email. The
>whole point being that genuine email will retry, spammers do not retry.
>Now we could implement this with exim, perl and mysql fairly easly. But
>wondered what people thought of it as a policy.
>
>Personally I think it is bad etiquette and unfair on the sending MTA,
>but on the other hand as most of the MTAs you deal with a lot will be in
>the database it should not be too much of a problem.
>
>I would appreciate any feedback on this as some people think we should
>spend squillions of pounds on this 'professional' system rather than our
>free system which is IMHO infinitely better.
>
>Ron
>
>
--
Marc Perkel - marc@???
Spam Filter: http://www.junkemailfilter.com
My Blog: http://marc.perkel.com
My Religion: http://www.churchofreality.org
~ "If it's real - we believe in it!" ~
