North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Mail Server best practices - was: Pandora's Box of new TLDs
Rich Kulawiec wrote: Quoting <http://www.postconf.com/docs/spamrep/> : A bit of a Red Herring as nobody expects 100%. Second, while in principle this isn't a bad approach, in reality it tends not to work well.
Not that any ISP delivers everything (since ~1996). The ones that try learn a hard lesson in DOS or they lose customers (remember netcom.com). The issue isn't delivery, it's reporting, and only ISPs that inform users about _every_ rejected or discarded email are capable of effectively minimizing false positives. It requires that users weed through the daily reports
and it requires accepting and storing considerable volumes of mail which are likely spam/phish/virus/etc.
can make FP detection difficult, since senders do not get a reject (mail was accepted, after all; why should they?) and thus may be unaware that their message was dropped in a probable-spam folder.
Whether spam is rejected outright or discarded after delivery is not relevant since good reports list both. Users don't make a distinction either, as long as they know what was filtered. Whether to A) reject or B) accept and discard is also a bit of a red herring. Most spam will get reject by RBLs but you still _must_ run everything else through Spamassassin and AV, and there's no way to do those checks pre-queue without SMTP timeouts and DOS. Roger Marquis |