[Mimedefang] Blocking DSK & Cable modem users.

[listuser at numbnuts.net]

On Tue, 20 May 2003, Kenneth Porter wrote:

> --On Tuesday, May 20, 2003 1:54 PM -0700 Dave Shepherd
> <Dave.Shepherd at vixel.com> wrote:
> 
> > So is what I was thinking is that I would block all hostnames that had some
> > identifying string that would lend me think that it's a home computer.
> 
> There are RBL's specifically for that purpose. The better ones let those of us
> who do direct-to-MX knowledgeably request to be excluded. I had no problem
> getting my host removed from the dial-up class in this list:
> 
> <http://www.five-ten-sg.com/blackhole.php>

I stopped using 5-10-sg shortly after adding it for some reason.  IIRC 
they blocked something that I wouldn't have blocked.  I forget what 
though.  Looking at their site I see that they block all sorts of things 
that are far beyond what this guy asked for.

Dave, if blocking dialups is your intended goal then you should stick with 
lists that only block such.  Osirusoft.com maintains a seperate list of 
dialup IPs (dialups.relays.osirusoft.com).  MAPS has the original called 
the DUL, or Dialup User List (http://mail-abuse.org/dul/).

If you'd like to block more than that like vulnerable formmail.cgi 
machines, open relays, open proxies or SOCKs boxes then we can suggest 
many more lists for you to use.  If you'd like to specifically target the 
largest of the spammers then give the SBL a try (spamhaus.org).

> While looking up this URL I happened upon a new anti-spam system called
> "Distributed Checksum Clearinghouse":
> 
> <http://www.rhyolite.com/anti-spam/dcc/>
> 
> This might be a good thing to include in MD either directly or as another
> network test in SpamAssassin.

It really isn't new.  It's been around for going on 2.5 years.  Frankly I
wouldn't use DCC.  I looked into it some time back.  IMHO it's been far
surpassed by the likes of Razor and Pyzor by only listing human-confirmed,
spam rather than all mail in general list in DCC.  Because of this you
don't have a need for whitelists for Razor and Pyzor like you do with 
the DCC (at least for what we're discussing).

Justin