Welcome 09/09/2010 08:31:08 AM| Welcome 09/09/2010 08:31:08 AM |
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 | Here's link to our presentation on how DNSBL works. Here's a list of the DNSBL that we used to use
We can white list any mail servers if needed. Some other servers
In a recent post from Slashdot, ariehk writes "As of today, Osirusoft, distributer of the SPEWS and open relay blocklists, among others, is no longer operational. Servers using these lists (including the FTC) are currently rejecting ALL email. This shutdown seems to be in response to a several-week-long DDoS attack on Osirusoft, SPEWS and others, resulting in both sites being down. This has caused much discussion on n.a.n-a.e, including the suggestion that the attack is somehow related to the SoBig worm. The spammers must be hurting if they can devote these kinds of resources to attacking blacklists." Ouch! If you were one of many companies using one of these blacklists, we feel your pain. Spam is, for many individual Internet users and businesses, high on the list of biggest annoyances these days. Consequently, a number of different methods have been developed to try to cut down on the amount of unsolicited advertising that reaches users' mailboxes. There are software programs to block spam at the ISP level, at the internal mail server, or at the client machine. The challenge is in determining exactly what mail is spam - probably the second most frequent spam-related annoyance is that of "false positives," when the filtering software filters out mail that you do want to receive. Different software programs have different ways of doing this. Some flag key words in the subject line or content, while others rely on blacklists (or blocklists) that contain the IP addresses and/or domain names of suspected or verified spammers. Services such as SPEWS compile these lists and distribute them, saving admins the time and effort of putting together their own. However, one of the problems inherent in using a blacklist service is that it's vulnerable to attacks such as the one discussed above. Another is the fact that no one really knows exactly what criteria is used to build the lists, and innocent non-spammers end up getting blacklisted. |
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