[Cryptech Tech] Avalanche noise test boards

[Peter Gutmann]

Fredrik Thulin <fredrik at thulin.net> writes:

>There's also some interesting documentation on the site - like test output
>showing that they too "fail" to get a good chi square number from 'ent' with
>just raw avalanche noise data (here:
>http://moonbaseotago.com/onerng/theory.html).

I've talked to a few commercial vendors and many of them fail one or more of
the more rigorous tests, which is why they all postprocess the raw noise.
That way it doesn't matter if the noise is biased in some way, as long as it's
unpredictable it doesn't have to be white noise since the postprocessing will
add that.

(Think of the canonical perfect RNG, a Geiger counter fed from radioactive
decay, it's extremely biased since most of the time it's outputting nothing,
but also extremely unpredictable for the events it outputs).

Peter.