bulk postage fine (was Re: non-censorous spam control)

[Adam Back <aba@dcs.ex.ac.uk>]

Kent Crispin <kent@songbird.com> writes:
> In more general terms: A "free market" fundamentally grants more
> control to those with more money.  Postage of whatever variety turns
> the medium over to those with more money.  That would, in my opinion, 
> fundamentally alter the character of email in a strongly negative 
> direction. 

OK, lets say we make emails free, unmetered, but they _must_ include a
valid token for 0c.  (OK Dimitri?)

Next we choose a threshold say 1000 posts per day.  Seems hard to
imagine anyone generating manually over 1000 emails per day.  That's
more than 1 per minute for a 10 hour day.

Next when you sign up for this new email postage system, you have to
hand over a $100 deposit.  The 0c payments are anonymous.  But if you
spend over 1000 of them in one day, your identity becomes known (via a
mechanism like that used for Chaum's off-line double spending
detection protocol).  You loose $100.  To you, the spammer, the posts
cost 10c each.  Your account is disabled until you pay another $100.


However there are a number of practical problems with the above scheme:

- How do we stop spammers buying unwanted 0c postage stamps from
people for under 10c a stamp?

- Sounds like an online protocol, will be high bandwidth requirements
at the bank(s)

- How do we stop banks cheating and spamming or selling spammers
postage more cheaply

Doesn't look like it could work, unless anyone has any ideas to fix-up
a distributed protocol which can acheive something like this, and
preserve anonymity at the same time.

Adam
-- 
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