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Re: greylisting

  • From: Suresh Ramasubramanian
  • Date: Fri Feb 06 22:21:34 2004 
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.

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