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. ---------:---------:---------:---------:---------:---------:---------:---- Timothy C. May | Crypto Anarchy: encryption, digital money, tcmay@got.net 408-728-0152 | anonymous networks, digital pseudonyms, zero Corralitos, CA | knowledge, reputations, information markets, Higher Power: 2^756839 | black markets, collapse of governments. "National borders are just speed bumps on the information superhighway."