From: Tatu Ylonen <ylo@cs.hut.fi>
Date: Thu, 23 Nov 95 06:32:25 PST
To: raph@c2.org
Subject: Re: Design proposal: crypto-capable generic interface
In-Reply-To: <Pine.SUN.3.91.951122094209.29001A-100000@infinity.c2.org>
Message-ID: <199511231334.OAA00460@trance.olari.clinet.fi>
MIME-Version: 1.0
Content-Type: text/plain


>    Ok. But public keys have one serious disadvantage: their size. I can't 
> put a public key on my business card or read it over the phone. I want a 
> unforgeable key name. I want this to be the standard key name in the 
> interface between the application and the crypto engine. I want users to 
> be able to specify them directly, at the very least to bootstrap the 
> public key infrastructure.

There is a patent by someone (I think it was IBM) on how to pack RSA
keys in small space.  I think they were putting them on the magnetic
strips that you have behind every card.  I'm afraid I don't have the
patent number saved, but I have seen the patent document myself at the
patent office.  No, I'm afraid I don't remember how they encoded it.

Using that method (or something similar), you could probably encode
the keys into acceptably short strings with S/KEY-style encoding.

    Tatu