[Mimedefang] greylisting

Steffen Kaiser skmimedefang at smail.inf.fh-bonn-rhein-sieg.de
Tue Nov 25 03:07:13 EST 2003

On Mon, 24 Nov 2003, Alan Madill wrote:

> > I implemented greylisting on the 23rd.
> > (read the archives if your wondering what greylisting is.)
> > And I am just completelly amazed at how effective it is at bouncing spam,
> > and also dropping the load on my mail server.
> The original article said that greylisting was effective on short time

You've forgot that to tempfail a mail does not involve (usually) a
notification of the sender; it's just that the sending MTA re-transmits
the mail.

Also, I know that many people believe that mail is an instant messaging
tool nowadays, but some way all of them learn it is not.

> The next resend goes through or they resend.

When the sender simply sends the _same_ mail two times, s/he is
already approved once the second mail arrives, because all the currently
suggested greylisting approaches does not key the message ID, but the
sender's email address.


Steffen Kaiser

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