[7283] in cryptography@c2.net mail archive
Re: random seed generation without user interaction?
daemon@ATHENA.MIT.EDU (Steven M. Bellovin)
Wed Jun 7 21:59:53 2000
From: "Steven M. Bellovin" <smb@research.att.com>
To: John Kelsey <kelsey.j@ix.netcom.com>
Cc: cryptography@c2.net
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Date: Wed, 07 Jun 2000 21:11:16 -0400
Message-Id: <20000608011132.0E7A435DC2@smb.research.att.com>
In message <4.1.20000607054551.00952f00@email.plnet.net> <4.1.20000607054551.00
952f00@email.plnet.net>, John Kelsey writes:
>At 10:33 PM 6/6/00 -0400, Arnold G. Reinhold wrote:
>
>...
>>The patent appears much broader than just focusing a camera on a Lava
>>lamp. They claim digitizing the state of any chaotic system and then
>>hashing it to seed a PRNG. The Lava lamp is given as a specific
>>example (claim 3).
>
>Wouldn't Don Davis' work on hard drive timings, in which he specifically
>claimed that the system was chaotic, qualify as prior art for this?
>
>[Wouldn't all the work done on things like hashing inputs in general
>to distil entropy, which was around for years before this patent,
>count? --Perry]
Perry's point is actually more pertinent. If you read the patent,
they explicitly cite use of chaotic systems as prior art. But they
point out that such a system may be deterministic over a short enough
interval. They therefore propose the "novel" step of hashing the
output of the digitized chaotic system...
Now, where did I put my datasheet for the AT&T 7001 chip, which did in
fact hash the output of one of the chaotic sources they specifically
cite?
--Steve Bellovin
