From: Jiri Baum <jirib@sweeney.cs.monash.edu.au>
Date: Wed, 25 Oct 95 21:25:28 PDT
To: hfinney@shell.portal.com (Hal)
Subject: Re: How can e-cash, even on-line cleared, protect payee identity?
In-Reply-To: <199510241425.HAA06922@jobe.shell.portal.com>
Message-ID: <199510260424.OAA12383@sweeney.cs.monash.edu.au>
MIME-Version: 1.0
Content-Type: text/plain


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Hello Hal <hfinney@shell.portal.com>
  and cypherpunks@toad.com

H wrote:
> Jiri Baum <jirib@sweeney.cs.monash.edu.au> writes:
...
> >An interesting question is whether Bob and Nick can now collude to
> >expose Alice. Therefore Alice would at least want to verify that the
...
> 
> I don't think they can.  All Bob sees is his own blinded coin, and the
...

What I meant is, are there any proto-coins that will show through
a blinding? (Mathematically special values like fixed points.)

> However, the timing is a problem.  Bob knows _when_ Alice communicated
...

So it is.

What you'd really want is for Alice to pay for the new coins in ecash.


I'm wondering whether a "coin-changer" would be easier or harder to
set up than a "bank" (from regulatory point of view).

After all, for e-cash you don't really need accounts; you just need:
  - verify coins (coin-changer) ie ecash->ecash
  - buy coins (join the system) ie  cash->ecash
  - sell coins (redeem)         ie ecash->cash

Any cyberspace banks can be completely separate from the ecash issuer.


Jiri
- --
If you want an answer, please mail to <jirib@cs.monash.edu.au>.
On sweeney, I may delete without reading!
PGP 463A14D5 (but it's at home so it'll take a day or two)
PGP EF0607F9 (but it's at uni so don't rely on it too much)

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