From: tcmay@got.net (Timothy C. May)
Date: Fri, 8 Dec 95 13:19:00 PST
To: Jerry Whiting <cypherpunks@toad.com
Subject: Re: The Elevator Problem
Message-ID: <acedea6511021004dea8@[205.199.118.202]>
MIME-Version: 1.0
Content-Type: text/plain


At 6:47 PM 12/8/95, Jerry Whiting wrote:
>A group of us have been wrestling with a problem and I'd like to ask for some
>outside help.  We've come to call it the Elevator Problem.
>
>Alice and Bob want to establish a secret in from of Eve.  In other words,
>they want to agree on a secret key in an elevator full of Eve's.

Isn't this just the "subliminal channels" scenario? Originally phrased in
terms of prisoners under the watchful eyes of their jailers nevertheless
establishing a private communication channel?

Schneier describes this beginning on page 66 (of his 1st edition).

Your scenario looks identical to this. So you should check out the papers
on this in the Crypto Conference proceedings.

As to whether you can implement this without using patented algorithms, I
don't know. Not enough information given.

--Tim May

Views here are not the views of my Internet Service Provider or Government.
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Timothy C. May              | Crypto Anarchy: encryption, digital money,
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