Re: Does this have a flaw in de-biasing an entropy stream?

David Wagner wrote:
Terry Ritter wrote:
David Wagner wrote:
Terry Ritter wrote:
Indeed, the sample value distribution of noise should
be close to a "normal" (Gaussian) curve instead of the
"flat" (even) distribution most users want.

That depends on the noise source. Some noise sources are closer
to Poisson (Geiger counters); some are Gaussian; some are binary
(discrete events).

Many technical people reserve the word "noise" to
refer to a class of analog signal we might describe
as "hiss."

Ok. If we define "noise" to mean a physical randomness source that has
the Gaussian distribution, then certainly any "noise" source will has the
Gaussian distribution -- that's more or less tautological.

It is no tautology to say that a good noise
generator must have a good normal distribution,
since many do not.


My point was
just that there are other sources of physical randomness with other kinds
of random distributions. But I guess this is a tangent; sorry.

Relatively few sources of randomness have a
physical model which implies something we can
usefully measure. Having a way to expose
fundamental source problems is an unusual
and important advantage.

---
Terry Ritter 1.4MB Crypto Glossary
http://www.ciphersbyritter.com/GLOSSARY.HTM

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