Stealth Blocking

Jason Slagle raistlin at
Thu May 24 19:56:30 UTC 2001

On Thu, 24 May 2001, Mitch Halmu wrote:

> The collateral damage in blocking 100,000 hosts is simply unacceptable.
> Especially because there are only a few hundred die-hard professional
> spammers that need to be rooted out, and the problem diminishes, or at
> least becomes manageable in another way. As an ISP, I have yet to see
> a list of black sheep compiled consisting of individuals, spam companies, 
> or credit cards used to defraud that should not be subscribed. Banks
> share such information, why can't ISPs?

Assuming that 25% of the IP space is assigned, and 1% of IP space assigned
is a mail server, that is still blocking only 1% of mail servers.

I know more then 10 million mail servers exist.

Along those lines, let me get this straight.  You support someone
compiling a list of spammers that you won't sell to, but you oppose
someone compiling a list of people that I choose not to accept mail
from.  That is quite interesting, and somewhat hypocritical.

> No matter how noble the cause, the methods are wrong. In all the debate, 
> it was perhaps lost that no viable technological solution to roaming, 
> meaning one that is happily accepted by the end user, exists yet. And 
> please don't mention SMTP Auth, it's not perfected yet.

We tell users that if they roam they need to use the mail server of the
place they are roaming to.

As a matter of fact, we are in the process of setting up a set of rules to
divert all port 25 bound traffic on our dialups to local mail servers.

If everyone diverted all local traffic to a local mail server, the problem
of open relays would go away.


Jason Slagle - CCNP - CCDP
Network Administrator - Toledo Internet Access - Toledo Ohio
- raistlin at - jslagle at - WHOIS JS10172
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