[cryptography] Intel RNG

James A. Donald jamesd at echeque.com
Wed Jun 20 02:40:02 EDT 2012

On 2012-06-20 2:17 PM, David Johnston wrote:
> If an entropy source in a closed system is producing an apparently non
> repeating, unbiased sequence and its output is deterministic (or low
> entropy) then there must be internal memory in the entropy source that
> is enabling the non repeating behavior. The more memory, the longer you
> have to watch before you can identify repeating behavior.
> So make your entropy source have a very small amount of memory and be
> sufficiently simple that you can model it mathematically. Then you can
> show all the SPOF and DPOF failure modes and show that your health check
> circuitry catches them.

The whitener has a very large amount of memory.

So I would prefer the entropy source to be separate and separable from 
the whitener, so that it could be checked by software, not hardware.

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