From: Alex Strasheim <alex@omaha.com>
To: cypherpunks@toad.com
Message Hash: 8b23865cfae8e91165bd6bd7e5d9483862fbae835105220905de989f9266a9d7
Message ID: <199412082010.OAA00148@omaha.omaha.com>
Reply To: N/A
UTC Datetime: 1994-12-08 20:09:51 UTC
Raw Date: Thu, 8 Dec 94 12:09:51 PST
From: Alex Strasheim <alex@omaha.com>
Date: Thu, 8 Dec 94 12:09:51 PST
To: cypherpunks@toad.com
Subject: cut & choose
Message-ID: <199412082010.OAA00148@omaha.omaha.com>
MIME-Version: 1.0
Content-Type: text
-----BEGIN PGP SIGNED MESSAGE-----
In Applied Cryptography, Schneier describes digital cash protocols that
depend on the cut and choose method: Alice prepares 100 anonymous money
orders for $100, sends them all to the bank, which opens all the envelopes
except one picked at random. If the 99 envelopes checked have money
orders for $100, then the bank is confident that the one they sign blindly
will be for $100 as well.
Chaum's system uses different keys for different denominations. Alice
only sends one envelope, and the bank uses its $100 key to sign it.
I don't understand why anyone would use the cut and choose protocol over
denominated keys. Chaum's method seems a lot cleaner to me and more
secure. It obviously uses less bandwidth. What am I missing here?
==
Alex Strasheim | finger astrashe@nyx.cs.du.edu
alex@omaha.com | for my PGP 2.6.1. public key
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=fzJT
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