In message <[EMAIL PROTECTED]> <4.1.20000607054551.00
[EMAIL PROTECTED]>, 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