Random Number seeds, was RE: First computer with real-time clock?

From: John Lawson <jpl15_at_panix.com>
Date: Mon Aug 2 11:57:33 2004

On Mon, 2 Aug 2004, Paul Koning wrote:

> Htz? You mean Hz?

  Nits? Are we going to have a spirited discussion or are you going to pick
nits? (While you're at it, might as well bag on my execrable spelling and
egregious transposition errors, all firmly rooted in slowly advancing
presbyopia and the need for (yet another) set of trifocals.)

   I have to force myself not to write cps, or Kc, or Mc...

>
> What I was reacting to is the notion of a receiver "tuned to a local
> station". A radio signal is quite far from random, and if a cryppie
> were to use such a thing for generating keys he would be at serious
> risk of a successful attack.

   If sampled at 'occasional' intervals, and the resultant digitized
samples are averaged and truncated, one approaches a fine approximation of
statistical chaos. I'm not saying it's the most efficient, or even sorta
practical, way to generate a random string of numbers, but it *was*
interesting, and it bore upon the topic of this list, and the discussion
at hand.

>
> Now if you were to take a radio tuned to an unused channel, that would
> be somewhat better. But still it would be subject to unexpected
> biases from stations far away. A self-contained device such as an
> electrical noise source is much simpler AND it is much easier to prove
> that it has the right properties.
>
> By the way, re the AT&T random number generator whose properties were
> unproven -- these days, most of the designers of these devices *are*
> prepared to show adequate proof, as well they should of course.

   Citation? URL? This is not familiar to me.


>

   All this is rapidly descending into Deceased Equine Flagellation... the
points are evident that it is possible to feed a random number generation
system with various chaotic signals derived from various well-known
processes, and derive therefrom a suitably "random" series of
as-unrelated-as-possible numeric values.....


   Cheerz

John
Received on Mon Aug 02 2004 - 11:57:33 BST