[PLUG] Re: Spam Elimination

[Tom Diehl <tdiehl@rogueind.com>]

On Wed, 2 Feb 2005, Doug Crompton wrote:

> Jeff,
> 
>  I get your point but I am on the side of a hard stand on this. Some areas
> of the world are nothing but spam factories, like Korea. The only way it
> is going to stop is shut the flow off. If enough big guns did that maybe
> the countries would get tough on it. I am also in favor of some kind of
> either government or privatly funded entity that would make lists that
> private organizations could optionally use to filter mail. We kind of have
> that now with the DNSBL's and published spam lists but they are private
> and their is no promise they will be there tomorrow. If all of the big
> companies anteed up and funded such an effort I think it could work. Right
> now you have many companies working on abuse but not really sharing
> anything. Most of this crap comes from outside the US. If a country does
> not show an effort to fix the problem then shut'em off! Fortunately I do
> not have to worry about lawsuits. That is another reason why a tough law
> is needed. To protect the companies that protect their 'legal' customers.
> 
> If anyone wants my list and methods for spam reduction I would be glad to
> share it.
> 
> On Wed, 2 Feb 2005, Jeff Abrahamson wrote:
> 
> > On Wed, Feb 02, 2005 at 01:38:25PM -0500, Doug Crompton wrote:
> > > I have most countries outside of the US blocked. I have no need
> > > to get email from anywhere outside of the US and if I do I will whitelist
> > > them individually.
> >
> > If you hear about them.

Right!! You say you do not need any mail outside the US but are you sure? All
it takes is for you to be on a mailing list that has people in other countries
that you wish to converse with privately. You may never know if the person
in another country has the correct answer that you have been looking for for
months. Maybe you missed the message he/she sent to the list because of the
high volume of traffic on that list. :-)

I have used spamassassin and a couple of RBL's with pretty good success.
I recently added grey listing to the mix. In spite of what some people
think of it, I can tell you it is VERY effective at blocking
large quantities of spam. The best part is my mail server never even accepts
the mail. As a result spamassassin never sees most of these messages. I have
a mail server that hosts about 50 domains. There are approx 100,000 connections
a day on an average day. Of that anywhere between 97-99% of the connections
are rejected because of greylisting and the 2 RBL's I use. The greater majority
of the connections never make it past the greylisting check. The best part is
people are noticing. I have gotten several calls asking if I had dome something
because they were no longer getting 99% of the spam. Sure a few still slip in.
I do not think it is realistic to expect to be able to eliminate 100% of the
spam without geting some legit mail. For me this is a good trade off.

If you are using postfix, I highly recommend postgrey.

Regards,

Tom Diehl		tdiehl@rogueind.com		Spamtrap address mtd123@rogueind.com
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