----- Original Message ----- From: "Russell Coker" <[EMAIL PROTECTED]> To: <debian-isp@lists.debian.org> Cc: "Pulu 'Anau" <[EMAIL PROTECTED]> Sent: Saturday, April 10, 2004 3:12 PM Subject: Re: OSF for an ISP (was Re: ..idea; ddos spam hosts off Internet?)
> For NT (XP etc) you could allow every fourth day for receiving mail. Mail is > generally queued for four days before being bounced, so if you only accept > mail from NT machines every fourth day then you lose 75% of the spam and > viruses because spam proxies and viruses generally don't re-try. Legit mail > servers will keep trying until you let them through. > > Avoiding 75% of the spam and viruses isn't a solution to the problem, but > it's > a good start... > Have a look at http://www.greylisting.org/ and you could avoid much more spam while reducing false positives to nearly zero! Christian
