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NIST 800-90B recommends Section 4.4.1 Repetition Count Test & Adaptive Proportion Test for health test on Noise sources. In the equation to calculate the cut-off value C for Repetition Count Test, C = 1 + [-log_base_2 Alpha / H]; Alpha is 2^-20 but how is Min Entropy H being calculated ?

In the equation to calculate the cut-off value C for Adaptive Proportion Test, C= 1 +CRITBINOM(W, power(2,(-H)),1-Alpha); W = 1024, Alpha = 2^-20, How is the min Entropy H being Calculated ?

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Clearly the installation of health tests must come after the development of the entropy source. As part of that development, you'd need to assess the min.entropy of your new system under whatever sampling methodology you choose. And Min Entropy H comes out of that assessment. It is "the min-entropy of the samples from a (digitized) noise source or of the output from an entropy source; the min-entropy assessment for a noise source or entropy source."

NIST suggests two tracks, either:-

  1. Confirm IIDness via permutation testing, and take min entropy as log(Pmax[]).

  2. Estimate it on the basis of a non-IID hypothesis using the methods of § 6.3 Estimators.

It's all detailed in §6 Estimating Min-Entropy. Track 2 is known to be unreliable as our measurements of entropy of non-IID sources are still inadequate. I recommend that the tightest bounds on measuring Min Entropy H will be achieved by evolving your sampling methodology to obtain IID samples.

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  • $\begingroup$ one comment seeing you are new. you can edit your answers, no need to delete and enter a new answer. $\endgroup$ – kodlu Jan 15 at 21:39

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