From: Bill Stewart <bill.stewart@pobox.com>
Date: Fri, 20 Feb 1998 17:33:29 +0800
To: Fisher Mark <cypherpunks@cyberpass.net>
Subject: RE: financial incentives for hashcash?
In-Reply-To: <83C932393B88D111AED30000F84104A70A1F27@indyexch_fddi.indy.tce.com>
Message-ID: <3.0.5.32.19980220012637.008994c0@popd.ix.netcom.com>
MIME-Version: 1.0
Content-Type: text/plain



At 12:13 PM 2/17/98 -0500, Fisher Mark wrote:
>I am curious -- does anyone have any statistics on how much spam (what
>percentage) is done via SMTP relay?  To me, using the SMTP service of
>someone/something you don't know to send 1000's/10,000's/more of email
>messages seems pretty unfriendly at best.  

Yes, it's one of the major techniques used by spammers;
the other big one is disposable accounts.
maps.vix.com has information about the Realtime Blackhole List
system, which lets you configure your sendmail system to reject
incoming mail from any system that permits relays,
and provides lots of information about setting your system
not to do relays.  They're a bit inflexible,
but if you're up to rolling your own sendmail.cf code,
you can fix that.
				Thanks! 
					Bill
Bill Stewart, bill.stewart@pobox.com
PGP Fingerprint D454 E202 CBC8 40BF  3C85 B884 0ABE 4639