From: Bill Stewart <stewarts@ix.netcom.com>
Date: Sat, 27 Jul 1996 16:35:48 +0800
To: cypherpunks@toad.com
Subject: Gambling Protocols
Message-ID: <199607270636.XAA15637@toad.com>
MIME-Version: 1.0
Content-Type: text/plain


>>If Phil really believes he and I are at any credible legal risk 
>>for a making such a personal wager, he is a fool. 

The obvious approach is for some kind person to send encrypted 
email to both Phill and Sandy and offer to hold their digicash in escrow.
What kind of protocol would it take to implement this correctly?  
The escrow agent needs to verify that the e-money is good 
(though not necessarily where it came from), and perhaps put some
kind of lock on it to prevent double-spending by the bettors.  
The bettors need to be able to verify that the escrow agent hasn't
ripped them off.  (The escrow agent may have a certain amount
of reputation with the two players, but may not be in a regular
escrow business so he may be willing to rip them off, unlike a bank
which probably doesn't want to risk its reputation.  In a typical
betting-escrow situation today, the escrow agent doesn't need
much reputation because he's right there while the two bettors
are arm-wrestling, shooting pool, trying to out-drink each other,
or whatever, so he can't really abscond.)

Non-payer-anonymous double-spender-identifying e-money would be one 
approach - if the escrow agent rips them off, he's traceable,
and if one of the bettors double-spends, he gets fingered.
Perhaps the escrow agent should deposit the money (and a key)
with the bank and get back an encrypted set of money and a certificate
saying the encrypted money is worth $X (which lets you use
basic Chaumian first-spender-wins e-money.)

Any better approaches?
#			Thanks;  Bill
# Bill Stewart, +1-415-442-2215 stewarts@ix.netcom.com
# <A HREF="http://idiom.com/~wcs"> 
#			Dispel Authority!