RE: spamcop
On Thursday, September 21, 2006 2:33 PM -0500, John Kelly wrote:
> On Thu, 21 Sep 2006 14:53:28 -0500, "Seth Goodman"
> <sethg@GoodmanAssociates.com> wrote:
>
> > > The improper DNS false positive rate is low, less than 2%.
>
> > It's a pity, but very few people think in terms of winning the
> > spam war anymore. Most systems would consider this false
> > positive rate unusable by a large margin. The larger the
> > provider, the less workable this solution.
>
> That's the fear factor.
>
> But once you get a grip and hang on for a while, you realize that
> sacrificing 2% is a piece of cake.
If users value reliably getting their messages more than they value spam
reduction, which seems to be the case, it will cost you. Large system
admins are not fools. They have tried this and people don't accept it.
It works nicely for small systems but the administrative overhead makes
it hard to run a large system that way. It's also grossly unfair to
people in some developing regions who don't have control over their rDNS
and we can't tell them to "get a grip". I hope things change and we can
require forward == reverse in the future. If that happens on a large
scale, spam-friendly providers can just use dynamic IP hostnames that
are not detectable via regexp :)
--
Seth Goodman
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