One other suggestion: instead of storing one bit of information (the address is on the list or not), why not have several flag bits. E.g., the blocking list could contain records similar to: hash - e.g. 160-bit SHA flags - e.g. reserve 32 bits ... Any suggestions for flags besides block/allow one-way, block/allow two-way, and max-size?
Here are two more ideas: 1. A bit to indicate that the recipient doesn't want to receive anonymous e-mail if it contains the strings "fuck", "piss", "shit", "cunt", etc. Of course, this can be circumvented with "f*ck u c*nt", but it shows good faith. 2. Limit the maximum number of e-mails that one remailer can send to this address in a 24-hour period. I'd suggest using 2 bits: 00 - unlimited 01 - 10 / day 10 - 100 / day 11 - 1000 / day with the default being 10 / day for addresses not in the database and also for addresses added to the preferences database w/o specifying otherwise. Thus, if you do expect to receive more than 10 anonymous e-mails / day via one remailer, you must add your address to the database, not necessarily blocking anythihg, but specifing that you want 100, 1000, or an unlimited number of messages in a day. When the count goes over the limit, a single e-mail is sent to the recipient saying that there may be an attempt to mailbomb him, that some of his e-mail was being junked, and that he can change the settings if he wants to. This should prevent the kind of abuse you've described. --- Dr.Dimitri Vulis KOTM Brighton Beach Boardwalk BBS, Forest Hills, N.Y.: +1-718-261-2013, 14.4Kbps