From: "Rev. Mark Grant" <mark@unicorn.com>
Date: Thu, 27 Jul 95 07:03:23 PDT
To: cypherpunks@toad.com
Subject: Re: Full text of David Chaum's Congressional speech
Message-ID: <Pine.3.89.9507271436.A20183-0100000@unicorn.com>
MIME-Version: 1.0
Content-Type: text/plain



On Thu, 27 Jul 1995, Marcel van der Peijl wrote:

> Ecash itself is less
> prone to abuse than paper bank notes, because privacy is "one-way,"
> which means that an extortionist, a seller on a black-market, or the
> acceptor of a bribe is forever vulnerable to being irrefutably
> incriminated by the party that paid them.

Now, I'm not sure of this, but as far as I can see, if I was a 
blackmailer wanting to receive an untraceable payment I could do the 
following :

	I create my ecash serial number/hash
	I blind it with a random number
	I send it to the payer

	Payer blinds it again and sends it to the bank
	
	Bank signs it and returns it

	Payer removes their blinding and returns the result to me

	I remove my blinding and send it to the bank for payment with
	no chance of being traced.

Will this work ?

		Mark