From: ph@netcom.com (Peter Hendrickson)
Date: Fri, 15 Nov 1996 21:50:42 -0800 (PST)
To: Hal Finney <cypherpunks@toad.com
Subject: Re: Playing Cards
Message-ID: <v02140b01aeb302e6b38c@[192.0.2.1]>
MIME-Version: 1.0
Content-Type: text/plain


At 7:04 PM 11/15/1996, Hal Finney wrote:
>From: ph@netcom.com (Peter Hendrickson)
>> A well shuffled deck of 54 cards has about 237 bits of entropy.  This
>> is easy to use: the program asks the order of the cards, converts this
>> to a string, and runs it through a one-way hash.  (Entering the cards
>> is a bit of a nuisance.  Is there an easy way to have them read
>> automatically?)

> I heard that Bruce Schneier has devised a cryptosystem based on a card
> deck for a future book by Neal Stephenson.  It is supposed to be simple
> enough for a person to use manually, but complicated enough that it can't
> be broken by computer.  Your idea of using cards as a one time pad is
> somewhat similar, maybe, although I think Bruce's was designed to be
> useful for long messages, providing computational rather than unconditional
> security.

I, for one, am dying of curiousity.  When I asked him about it, he said
he would disclose it "soon".

Peter