Random Number seeds, was RE: First computer with real-time clock?
On Mon, 2 Aug 2004, Paul Koning wrote:
>>>>>> "John" == John Lawson <jpl15_at_panix.com> writes:
>
> John> Computer-based ramndom number seed generation:
>
> John> I may at some point remember the machine/manufacturer, but I
> John> *do* recall tha one (perhaps Gummint-oriented?) device used a
> John> standard radio buried in it somewhere, tuned to a local
> John> station, the output of which was digitized and the seeds
> John> extracted from that... as I write this, IISTR that it was some
> John> kind of crypto-thingy...
>
> That would be quite a bad idea. I'm sure the spooks are smarter than
> that.
And just why would that be a bad idea? Remember this was back some
years - your glib "these days" doesn't apply to 'them days'... in the
60's and 70's it was not trivial to develop 'real' random numbers, so
various means were used to sample a physical source or 'randomness'. I
have an audio whit noise generator (Grayson Stadler) that uses a 6CB4 tube
with a small bar magnet in proximity to the envelope - this exacerbates
the transit noise of the tube and produses a very nice 5 Htz to about 50
kHtz stream of chaos.
For many years, going back into the late 40s', microwave noise sources
(for testing and calibration) were made with a 2-foot flourescent lamp
mounted transversly at an acute angle through a section of waveguide -
when the microwaves passed thru the excited mercury vapor, the resultant
harmonics went into the gigahertz range...
Sheeshe! Kids nowadays! Why when *I* was your age,,,
Cheers
John
Received on Mon Aug 02 2004 - 09:20:18 BST
This archive was generated by hypermail 2.3.0
: Fri Oct 10 2014 - 23:36:32 BST