From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.emacs.gnus.general/45987 Path: main.gmane.org!not-for-mail From: Stainless Steel Rat Newsgroups: gmane.emacs.gnus.general Subject: Re: new spam functionality added Date: Sat, 03 Aug 2002 09:47:32 -0400 Organization: The Happy Fun Ball Brigade Sender: owner-ding@hpc.uh.edu Message-ID: References: <87y9brejam.fsf@mail.paradoxical.net> <873ctztyth.fsf@mail.paradoxical.net> <02Jul31.171132edt.119710@gateway.intersystems.com> <87fzxzsit2.fsf@mail.paradoxical.net> <87ofck96ic.fsf@deneb.enyo.de> NNTP-Posting-Host: localhost.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1028382533 23583 127.0.0.1 (3 Aug 2002 13:48:53 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Sat, 3 Aug 2002 13:48:53 +0000 (UTC) Return-path: Original-Received: from malifon.math.uh.edu ([129.7.128.13]) by main.gmane.org with esmtp (Exim 3.33 #1 (Debian)) id 17azH2-00068G-00 for ; Sat, 03 Aug 2002 15:48:52 +0200 Original-Received: from sina.hpc.uh.edu ([129.7.128.10] ident=lists) by malifon.math.uh.edu with esmtp (Exim 3.20 #1) id 17azGM-00061E-00; Sat, 03 Aug 2002 08:48:10 -0500 Original-Received: by sina.hpc.uh.edu (TLB v0.09a (1.20 tibbs 1996/10/09 22:03:07)); Sat, 03 Aug 2002 08:48:38 -0500 (CDT) Original-Received: from sclp3.sclp.com (qmailr@sclp3.sclp.com [209.196.61.66]) by sina.hpc.uh.edu (8.9.3/8.9.3) with SMTP id IAA17044 for ; Sat, 3 Aug 2002 08:48:22 -0500 (CDT) Original-Received: (qmail 16298 invoked by alias); 3 Aug 2002 13:47:46 -0000 Original-Received: (qmail 16293 invoked from network); 3 Aug 2002 13:47:45 -0000 Original-Received: from h0060978d8c91.ne.client2.attbi.com (HELO peorth.gweep.net) (jpcnpx@24.218.202.161) by gnus.org with SMTP; 3 Aug 2002 13:47:45 -0000 Original-Received: (from ratinox@localhost) by peorth.gweep.net (8.11.6/8.11.6) id g73DlWB02974; Sat, 3 Aug 2002 09:47:32 -0400 Original-To: "(ding)" X-Attribution: Rat In-Reply-To: (Simon Josefsson's message of "Sat, 03 Aug 2002 12:23:43 +0200") Original-Lines: 30 User-Agent: Gnus/5.090006 (Oort Gnus v0.06) XEmacs/21.1 (Cuyahoga Valley, i686-pc-linux) Precedence: list X-Majordomo: 1.94.jlt7 Xref: main.gmane.org gmane.emacs.gnus.general:45987 X-Report-Spam: http://spam.gmane.org/gmane.emacs.gnus.general:45987 * Simon Josefsson on Sat, 03 Aug 2002 | Pretty much so, I think. That's why I think hashcash needs to be | computed at the machine that sends the original mail; X-Hashcash that | is. The current implementation isn't very good though, as it stalls | Emacs while computing hashcash. X-Hashcash has problems in that there is no way to force spammers to use it, and any implementation is nontransparent to users. | Hashcash with ~< 25 bits is just a toy, you need more bits to make it | costly for spammers. Collision size in a proper hashcash implementation is "scoreable", so that known, trusted sources need a very small collision while spamhauses require much more. Consider: if $MAILSOURCE requires a collision that takes 6 seconds on average to calculate, that limits the number of messages it can send to $MYISP to 14400 per day. Legitimate mail sources, like ISPs with enforced anti-spam policies, will get low scores, requiring less than 0.25 seconds of calculation time, perhaps only 12-16 bits. ISPs who ignore spam complaints and allow it to be sent from their servers (gblx-cough-cough) will need 27-30 bits, effectively choking them off until they clean up their acts. At least, that is how my personal hashcash system would be configured; YMMV. -- Rat \ Ingredients of Happy Fun Ball include an Minion of Nathan - Nathan says Hi! \ unknown glowing substance which fell to PGP Key: at a key server near you! \ Earth, presumably from outer space. That and five bucks will get you a small coffee at Starbucks.