From: nelson@crynwr.com (Russell Nelson)
Date: Tue, 26 Jul 94 06:49:00 PDT
To: cypherpunks@toad.com
Subject: Re: CYPHERPUNKS TO THE RESCUE
In-Reply-To: <199407260711.AAA10426@netcom.netcom.com>
Message-ID: <m0qSmuj-000I8XC@crynwr.com>
MIME-Version: 1.0
Content-Type: text/plain


   Date: Tue, 26 Jul 1994 00:11:34 -0700
   From: norm@netcom.com (Norman Hardy)

   At 14:43 1994/07/25 -0700, Sandy Sandfort wrote:
   >The questions are:  Could standard auto and garage door openers
   >easily be retrofitted?  Could a "crypto remote" with its own CPU
   >be made small enough to fit into a hand-held unit?  Could such a
   >system be made for a reasonable cost?

   Sounds like an application for a "challenge-response" system. But that
   would require transmission from garage unit to car unit.

   If there were syncnronized clocks then the signal could be a function of
   time so that the above replay would fail. That requires only a PRNG.

Why not generate a random number, checksum it, and sign it using a
public key?  Or is that overkill?

-russ <nelson@crynwr.com>    http://www.crynwr.com/crynwr/nelson.html
Crynwr Software   | Crynwr Software sells packet driver support | ask4 PGP key
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