From: Antonomasia <ant@notatla.demon.co.uk>
Date: Tue, 16 Dec 1997 03:21:42 +0800
To: cypherpunks@ssz.com
Subject: Re: hashcash spam prevention & firewalls
Message-ID: <199712151830.SAA02083@notatla.demon.co.uk>
MIME-Version: 1.0
Content-Type: text/plain



Adam Back <aba@dcs.ex.ac.uk>:

> How about this alternative which achieves the same functionality and
> removes the juicy supeona target:

> Turn on hashash database for all mails.  That means hashcash gets put
> in the database to prevent double spending. ....

> So now when you reply to a message, on it's way out via the mail hub,
> you remove that hashcash token from the double spending database.
> This means that the sender can cache sent hashcash tokens, and re-use
> them when after he gets a reply.

Doesn't this invite the spammer to Bcc an accomplice with the
target ISP ?  The accomplice replies; thereby freeing the coin
for reuse.

> I am told by one subscriber to look at TIS firewall toolkits imap
> program.

You may have meant "smap".

--
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# Antonomasia   ant@notatla.demon.co.uk                      #
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