From: Bill Frantz <frantz@netcom.com>
Date: Thu, 19 Dec 1996 21:48:42 -0800 (PST)
To: cypherpunks@toad.com
Subject: Re: Executing Encrypted Code
In-Reply-To: <v02140b00aedf4a134af2@[192.0.2.1]>
Message-ID: <v03007805aedfd934dcf4@[204.31.236.106]>
MIME-Version: 1.0
Content-Type: text/plain


At 12:08 PM -0800 12/19/96, Peter Hendrickson wrote:
>If each chip has a unique public/secret key pair, and executes
>authenticated code only, there are some interesting implications.
>
>Software piracy becomes difficult, if not impossible.  Code is sold
>on a processor by processor basis.  Code for a different physical
>processor cannot be decrypted or executed.

This makes backup hard.  That is the rock the routine copy protection hit
up against.  There were many, me included, who simply said, "If your
product is copy protected then I will buy from your competitor."


>Viruses are not feasible if the authentication is strong.

So is user written code, public domain code etc.  If there is an
un-encrypted mode for that kind of code, then viruses again become possible.


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