At 3:27 PM -0400 6/6/2000, Steven M. Bellovin wrote:
>In message <[EMAIL PROTECTED]>, "Steven
>M. Bellovi
>n" writes:
>>In message <[EMAIL PROTECTED]>, Dennis
>>Glatting writes:
>>
>
> >>>
> >>
>>>There is an article (somewhere) on the net of digital cameras focused
>>>on lava lamps. Photos are taken of the lava lamps and mixed into a
>>>hash function to generate random data. I believe the author had some
>>>algorithm for turning the lamps on and off, too.
>>>
>>See lavarand.sgi.com.
>>
>
> >I had thought it was patented, but a quick search of uspto.gov didn't
>>turn it up.
>
>Following up on my own post... My brain clearly wasn't in gear when I
>did my previous search. It's U.S. patent 5,732,138; see
>http://patents.uspto.gov/cgi-bin/ifetch4?ENG+PATBIB-ALL+0+988124+0+6+
>31831+OF+1+1+1+PN%2f5%2c732%2c138
>
>
> --Steve Bellovin
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).
Arnold Reinhold
