I've been reviewing the DCC logs for messages that were rejected as bulk mail and subsequently whitelisted by users here. They fall into some interesting categories. Messages like customer notifications, newsletters, and other messages from mailing lists were generally detected as bulk mail by both Fuz1 and Fuz2 checksums. One that was in plain text was detected by all three checksums. One that used base64-encoding for both text and html portions was only detected by the Fuz2 checksum. These are all messages that users expect to be classified as bulk mail simply because copies are sent to many people.
At the other extreme are empty messages that contain only a PDF, DOC, or JPG attachment, as well as one-line messages in html format. These are all classified as bulk mail because of the Fuz2 checksum. Users send these all the time, and expect them to work because they are inter-personal messages. They don't expect them to be rejected, and can't understand why they need to whitelist them. In between are brief messages from web sites that contain passwords or authentication URLs. These too are often classified as bulk mail because of the Fuz2 checksum. Users expect them to work because they are part of the procedure described by the web site. They certainly don't think of them as bulk mail. I'd like to do something so that our DCC system would not reject messages in these last two categories. These are the ones that users don't expect to be bulk mail. I realize that I could whitelist checksums of empty message to alleviate that problem, but unless this process is automated, I'd have to be doing it regularly. We also advise people to add some text to empty messages, but that seems like a peculiar solution. Is there anything else I can do other than disabling the Fuz2 checksum? -- -Gary Mills- -Unix Group- -Computer and Network Services- _______________________________________________ DCC mailing list [email protected] http://www.rhyolite.com/mailman/listinfo/dcc
