Point of Information: Every single purely technical approach to stopping spam has been a complete loser. I understand the old adage that when all you have is a hammer the whole world looks like a nail. And that all many people on this list have is a technical hammer, some ability to hack around with cisco access lists or similar, so they tend to hold out hope that some new access list formula might be the one that saves the day (or similar, don't quibble the example!) But spam is as much a socio-legal problem as a technical one which is why, I'd claim, it's been so completely resistant to all purely technical approaches thus far. What we need are technical solutions which help with concomitant socio-legal solutions. If you haven't noticed, the spammers are winning completely, the waters are rising rapidly. More and more legitimate-sounding companies and products are spamming, and by and large the public perception in the non-anointed* business community are coming to the conclusion that they receive all this spam so it must be a legitimate form of advertising. Let me throw out the following to show how blind the technical community has been: There is no RFC or other public standards document which even attempts to define spam or explain, in a careful and professional manner, why it is a bad thing. (before you say the obvious, that's not what RFCs are for, read, e.g., RFC 2964) However, we expect lawmakers to recognize and define the problem and get it right when the engineers who understand the technology and problem, in nearly a decade of whining, can't even be bothered to provide them with robust definitions of what it is the whining is about. Food for thought, that's all. But, personally, I'm hesitant to spend my time trying to study the merits of yet another anti-spam miracle cure, even if it seems at first glance (like so many before) that it might foil some particular flavor of spam which has been prevalent in the past. Now, after sitting through this extended, multi-day discussion of spam someone can send me the standard "discussion of spam is not a subject for nanog!" because I'm not a member of the amen crowd. * "non-anointed": not a member of the technical community hence indoctrinated into a particular ethical view of what's right and wrong on the net. -- -Barry Shein Software Tool & Die | bzs@TheWorld.com | http://www.TheWorld.com Purveyors to the Trade | Voice: 617-739-0202 | Login: 617-739-WRLD The World | Public Access Internet | Since 1989 *oo*