Continued from page 1
Here's
process. A system is determined to be an open relay. It is added to one or more Blackhole lists. ISPs that subscribe to
lists will bounce (return to sender) any messages that originate from
open relay email system. This means ALL users from that email system are blocked. Every single one of them.
I know that seems cruel, but look at it this way. The open relay is encouraging spammers and is an unwitting accomplice in their operations. In fact, many of these open relays do not even know they are causing a problem, and
first inkling that they get is when their users complain that things are running slowly or when problems occur with their servers.
The Blackhole lists are often run by individuals or small groups who believe in
anti-spam cause. They are often unpaid volunteers who simply want to help clean up
internet. They are also extraordinarily successful and many ISPs use their services.
To give you an idea of how successful this approach has been, there was a blackhole list called ORBZ. This was run by a young man named Ian Gulliver, a 20-year-old systems administrator from Ghent, New York. Ian is an extraordinary person and created one of
most successful blackhole lists ever.
What ORBZ did is send messages to email systems to determine if they were open relays. If it determined that
email system had this problem it added it to it's list. This was very successful until
end of March, 2002.
At that time, ORBZ probed
email server of Battle Creek, MI. Unfortunately, this system used
Lotus email system, which has a known bug. The probe caused
email server to slow down considerably, and it was interpreted by
city as a hacker attack.
The poor ORBZ administrator found himself
subject of a search warrant signed by a Michigan judge that authorized
search and seizure of all data relating to ORBZ accounts.
Ian almost immediately shut down
ORBZ system (he reopened
service a few days later with some major changes and a new name), which led directly to a huge amount of spam suddenly being received all over
internet. The closure of a single blackhole list had dramatic and noticeable results.
The upside is that blackhole lists prevent a tremendous amount of spam from getting sent throughout
internet. They are very efficient and
concept is simple and straightforward.
On
downside, blackhole lists are not governed by anyone and answer to no one. They add open relays (and other spam sources) to their lists using their own rules, and usually assume
suspected spammer is guilty until proven innocent.
They are, however, a necessary and vital piece in
war against spam.

Richard Lowe Jr. is the webmaster of Internet Tips And Secrets at http://www.internet-tips.net - Visit our website any time to read over 1,000 complete FREE articles about how to improve your internet profits, enjoyment and knowledge.