Stamps vs SPAM

Francois-Rene Rideau Francois-Rene Rideau <>
Thu, 19 Sep 2002 03:00:32 +0200

On Thu, Sep 19, 2002 at 11:13:30AM +1200, Paul Foley wrote:
>> I'm also trying to find people who'd be interested in implementing
>> such email postage payment protocol and associated software.
> Done.  See

Well, AFAIU, hashcash (actually, the CAMRAM project that I cite,
that uses hashcash) implements postage payment by computational resource,
which is the least interesting payment method - it requires the sender
to install new software, and cannot be efficient against newer faster
spamming machines without screening out users of older slower machines.
It can be used as a way to avoid DoS of computer resource, but
not to avoid DoS of human resource - which is the only real scarce resource.

I'm looking for software that would implement payment in time, as is
done by many commercial websites requiring registration
(such as, for instance): to screen off automated programs,
the registration or login process includes recognition of some visual
or audio pattern, a task that only humans do correctly, for the time being.
So as to only ask such a "Turing test" to newcomers, and not be
a permanent annoyance to your regular correspondants, it is important
that the MUA also helps maintain contact information. etc.

Yours freely,

[ François-René ÐVB Rideau | Reflection&Cybernethics | ]
[  TUNES project for a Free Reflective Computing System  |  ]
The greatest productive force is human selfishness.
	-- Robert Heinlein