From: baum@newton.apple.com (Allen J. Baum)
Date: Thu, 27 Jan 94 11:17:38 PST
To: cypherpunks@toad.com
Subject: Re: clipper pin-compat - Not really
Message-ID: <9401271916.AA14712@newton.apple.com>
MIME-Version: 1.0
Content-Type: text/plain


I think we're missing the point here.

I think you want a chip that has the same pinouts and possibly
communication protocols as Clipper - I don't think you want or
need to know exactly how it encrypts or decrypts. You'd want to
use your own algorithm, not NSAs! Then, you can buy phones, replace
the chip with your own, and talk to anyone else with the same chip
securely. Further, it gives incentive for  ATT/whoever to start
producing phones with your chip, since they have very little additional
engineering to do.

So, the reverse engineering bit might not be so bad, since the
parts that are almost certain to get munged by peeling isn't what
you care about. Most likely, all you want to do is read a bunch
of ARM code ROM (if that is the controller inside it, which should be
easy to determine unpon inspection) to see how it talks to the outside
world, and talks to the encrypt/decrypt module. This sounds
a bit more tractable

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