the following is what pointed me toward the previous article about AOL and
spammers... Geo is a sysadmin for a north american isp and is very up on
his stuff... very interesting statistics he drops in the following...

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From: Geo.

Glenn Meadows wrote in a message

> The next release of Polarbar Mailer has  Bayesian filters added
> to it. > Others on the testing team have been working with them
> for several weeks now, and say they're very effective.

I'm seeing the end user point of view here but very little from the admin
point of view. So not to knock client side filters that can catch the spams
the ISP filters miss but there is more to consider here.

There are really 2 goals of spam filters, one is to keep the end user from
having to deal with 60 spams for every valid email (there was a study done,
I don't remember where, on the number of spams if it were acceptable to
spam and 60 per valid email was the ratio they came up with). The second
goal is to reduce the load on the mail system, the bandwidth usage to the
customer and to cause as many problems as possible for the spammers thereby
increasing their costs and decreasing the amount of spamming. It's this
second goal that client side filtering misses completely.

I was reading an article today about AOL winning a $7mil award against CN
Productions (a major spammer) and in the article they mentioned this:

"The complaint, originally filed in 1998, charged CN with sending AOL
subscribers nearly a billion e-mails advertising adult Web sites."

Now let me put that into perspective, your corporate mail server if it does
*nothing but email* is probably capable of doing between 1 and 2 million
emails a day (if it's on it's own T1 line), lets assume 1.5m per day. That
means your mail server would have to run flat out 24x7 for 1 year and 10
months just to handle the porno spams this guy sent to AOL. (this ignores
the DNS lookups and any mail forwarding)

Care to donate your mail server and a T1 line for a couple years just to
handle the porno spams sent to AOL from one spammer (we'll have someone
else donate a machine to handle the mortgage spams)?

Right now about half of all the mail being sent to nls.net addresses is
spam, and this is with a huge army of people on the net fighting the
spammers, imagine what it would be like if ISP's just said heck with it and
let the end users download and filter thus speeding up the spammers mail
servers and reducing their costs? You would be getting 60 spams for every
valid email. (I kid you not, stop fighting the spammers and just filter in
the client and this is a realistic number to expect) I would need 30 times
the capacity in mail servers for the same number of customers.

You guys complain about quotebacks... imagine 60 posts of quotebacks on
every new post. At what point would you consider it useless?

Geo.

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