Figure 1 shows a screen from MailScan for Linux, the top selling Anti Virus and Anti Spam software with features of White Lists and Spam Phrases.

Figure 1. White Lists and Spam Phrases
(click on the image for bigger view)

RBL and DUL Controls
MailScan for Linux should have a list of RBL and DUL to verify a users authenticity.

MAPS (Mail Abuse Prevention System) provides a list of IP addresses that are known Spammers or allow spamming. This list is called as Black hole list. When your server, receives a mail from a domain, not on its allow domain list, you can send a query to MAPS Server which verifies the IP.

Spammers sometimes use stealth mail tactics when their initial Spam attempts are blocked. They use a Dial-Up-Service (DUL) provider to connect their Spam mail service, to the server. This is trespassing on your MailServer and the MAPS DUL project helps in identifying and stopping Spam. The project has a list of DUL users who are known Spammers. To verify if the request for connection to your Server is genuine, you can send a query to dialups.mail-abuse.org. The request is verified and returned.

Figure 2 shows a screen from MailScan for Linux, the top selling Anti-Virus and Spam software for Linux mail servers with features of RBL and DUL.

Figure 2. RBL and DUL features
(click on the image for bigger view)

• Add e-mail ID of known Spammer to the block list. Any mails received from an ID, included in the list are automatically deleted, without being downloaded into your server.
• Add domains of known Spammers to the black list. Any mails received from such domains are automatically blocked, without being downloaded into your server.

Figure 3 Black List of Users and Domains
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