Services such as relays.osirusoft.com have come under fire recently for blocking legitimate e-mail as well as spam.
The service used a variety of techniques to maintain a real-time dynamic list of IP addresses that are known to have spam originate from them. By using the list in real time, a mail server can determine if it should accept and process a message or disregard it as spam.
Managing director of Australian broadband provider Ideal Internet Services, Darren Worley, doesn't use blacklists as a general rule. "We don't use them for various reasons... it's about controllability. You're passing control to some other entity, and if you're not in control of your own mail servers then it's a problem for your own business."
Lists such as Osirusoft are a good idea, Worley says, but don't work as well as they could because of practical concerns. "The alternative is a white-list. If you're a known, good custodian of a mail server and you're not an open relay then certainly a white list is an attractive option," he said.
However the goal of assembling a comprehensive black-list and a white-list "known spammer", "known responsible" database just isn't going to happen, Worley said. "It would take every mail server in the world to subscribe to it."
Mail servers still using the Osirusoft black list will not be able to receive mail until they are re-configured to use another blocking list.
At this stage no statement has been made from the operator of the service, but the industry speculates the service may come back in a different form when DDoS attacks have subsided.
Osirusoft may be gone, but there is still SPEWS to contend with. Our Editorial Opinion of 24 May 2003 outlines who we believe is responsible for SPEWS.
http://www.chatmag.com/help/spews.html