Re: greylisting

[Suresh Ramasubramanian <suresh () outblaze com>]

Ken Leland  [2/7/2004 2:11 AM] :

> On Fri, Feb 06, 2004 at 01:40:14PM -0500, Dmitri Krioukov wrote:
>
> > can someone provide any comments on greylisting?
> > how effective is it, etc?
>
>
> we have 20 regex expressions that block mail directly from a 
> reverse dns that "looks" like a consumer broadband connection. 
> Then we have to maintain a whitelist on a case by case basis.


Er, I think you and Dmitri are talking about different things.

From a mail operations standpoint, I am not a big fan of graylisting, 
because even legitimate senders get 4xx'd for a while, the first time 
they send mail.

When any such strategy means that someone else's mail queues are filled 
with timed out emails waiting for retransmission, it d not be rocket 
science to see why this just doesn't scale too well.

--
srs (postmaster|suresh)@outblaze.com // gpg : EDEDEFB9
manager, outblaze.com security and antispam operations