Patent ID: 8787564

Claim:
A method for assessing entropy in a cryptography system, the method comprising: obtaining a sample value produced by an entropy source system; determining a typicality grading for each of a preselected plurality of probability distributions, the typicality gradings providing a comparison among the plurality of probability distributions, the typicality grading for each individual probability distribution being determined based on the cumulative probability of values that are, according to that individual probability distribution, less probable than the sample value; wherein the typicality grading g k (x,p) for each individual probability distribution is determined according to: g k ⁡ ( x , p ) = ( ∑ y : P p ⁡ ( y ) < P p ⁡ ( x ) ⁢ ⁢ P p ⁡ ( y ) ) + k ( ∑ y : P p ⁡ ( y ) = P p ⁡ ( x ) ⁢ ⁢ P p ⁡ ( y ) ) , where k ε [0,1] represents an inclusivity level between zero and one inclusive, P p (x) represents the probability of the sample value x according to the individual probability distribution p, and y: P p (y) <P p (x) represents the values that are less probable than the sample value; selecting a subset of the plurality of probability distributions based on the typicality gradings; and calculating an entropy of the entropy source system based on the subset of the plurality of probability distributions.