From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 13 Nov 2010 19:43:43 +0100 From: Enrico Weigelt To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Message-ID: <20101113184343.GA17279@nibiru.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i Subject: [9fans] opposite of bloom filter Topicbox-Message-UUID: 7c304d86-ead6-11e9-9d60-3106f5b1d025 Hi folks, I'm currently looking for the opposite of an bloom filter, which may have false negatives but no false positives. The purpose is allowing an spooling (store+forward) mail relay to learn which addresses are not accepted by the actual maildrop (which is connected by an uucp-link, so no direct smtp chat), to get rid of the thousands silly error bounces from brute force attacks on email addresses. An trivial idea would be simply using an hashtable as blacklist, but obviously that would become very big. I need a more compact form, perhaps a subset of regex'es, a colored (b)tree, etc ? Any ideas ? thx -- ---------------------------------------------------------------------- Enrico Weigelt, metux IT service -- http://www.metux.de/ phone: +49 36207 519931 email: weigelt@metux.de mobile: +49 151 27565287 icq: 210169427 skype: nekrad666 ---------------------------------------------------------------------- Embedded-Linux / Portierung / Opensource-QM / Verteilte Systeme ----------------------------------------------------------------------