From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.emacs.gnus.general/45352 Path: main.gmane.org!not-for-mail From: Mark Milhollan Newsgroups: gmane.emacs.gnus.general Subject: Re: [ANNOUNCE] contrib/hashcash.el spam fighter Date: 23 Jun 2002 14:36:37 GMT Organization: yes Sender: owner-ding@hpc.uh.edu Message-ID: References: NNTP-Posting-Host: localhost.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1024843026 12269 127.0.0.1 (23 Jun 2002 14:37:06 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Sun, 23 Jun 2002 14:37:06 +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 17M8UD-0003Bk-00 for ; Sun, 23 Jun 2002 16:37:05 +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 17M8U4-0001MB-00; Sun, 23 Jun 2002 09:36:56 -0500 Original-Received: by sina.hpc.uh.edu (TLB v0.09a (1.20 tibbs 1996/10/09 22:03:07)); Sun, 23 Jun 2002 09:37:17 -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 JAA18448 for ; Sun, 23 Jun 2002 09:37:05 -0500 (CDT) Original-Received: (qmail 15293 invoked by alias); 23 Jun 2002 14:36:40 -0000 Original-Received: (qmail 15288 invoked from network); 23 Jun 2002 14:36:39 -0000 Original-Received: from quimby.gnus.org (80.91.224.244) by gnus.org with SMTP; 23 Jun 2002 14:36:39 -0000 Original-Received: from news by quimby.gnus.org with local (Exim 3.12 #1 (Debian)) id 17M8UF-0005yd-00 for ; Sun, 23 Jun 2002 16:37:07 +0200 Original-To: ding@gnus.org Original-Path: not-for-mail Original-Newsgroups: gnus.ding Original-Lines: 32 Original-NNTP-Posting-Host: adsl-209-78-192-139.dsl.lsan03.pacbell.net Original-X-Trace: quimby.gnus.org 1024843027 22978 209.78.192.139 (23 Jun 2002 14:37:07 GMT) Original-X-Complaints-To: usenet@quimby.gnus.org Original-NNTP-Posting-Date: 23 Jun 2002 14:37:07 GMT User-Agent: Gnus/5.090007 (Oort Gnus v0.07) XEmacs/21.4 (Informed Management (RC1), i686-redhat-linux) Precedence: list X-Majordomo: 1.94.jlt7 Xref: main.gmane.org gmane.emacs.gnus.general:45352 X-Report-Spam: http://spam.gmane.org/gmane.emacs.gnus.general:45352 Stainless Steel Rat writes: >* David Masterson on Sun, 23 Jun 2002 >| Why not? And, if the MUA can't, what part does this hashcash.el >| package (which, I assume, hooks into Gnus) play in things? > >Because it relies on the good faith of the sender. Spammers have none. > >I do not see what purpose hashcash.el can possibly serve, other than to >penalize legitimate senders while doing nothing to spammers. Hashcash is a rate-limiting tool -- forcing a compute intensive operation delays every message by some amount of time -- primarily useful to the anonymous remailer and Usenet posting networks. Most people only send a few dozen or hundred messages per day so they have more time to compute the hash than a spammer who is trying to deliver as fast as possible. MTA's that demand Hashcash are likely to drop connections that won't provide them (so far as I know none of these exist) or discard messages without them (these exist). Without code to handle it Gnus users will be at a disadvantage. The main down-side, which has kept it from being widely deployed for the 6+ years that the technique has been discussed, is that the bit length has to be set high enough so that spammers using high-end systems are impeded, yet that same setting tends to take a very long, perhaps intolerably so, time on an older system. I agree with you that it's a futile move, spammers will throw cycles at the problem and keep on spewing, while people with P90's will be limited to a few messages a day (as long as their system isn't doing anything else). /mark