Metric Pseudoentropy: Characterizations, Transformations and Applications [chapter]

Maciej Skorski
2015 Lecture Notes in Computer Science  
Metric entropy is a computational variant of entropy, often used as a convenient substitute of HILL Entropy, slightly stronger and standard notion for entropy in cryptographic applications. In this paper we develop a general method to characterize metric-type computational variants of entropy, in a way depending only on properties of a chosen class of test functions (adversaries). As a consequence, we obtain a nice and elegant geometric interpretation of metric entropy. We apply these
more » ... zation to simplify and modularize proofs of some important results, in particular: (a) computational dense model theorem, (b) derivation of the improved version of Leftover Hash Lemma and (c) equivalence between unpredictability entropy and HILL entropy for short strings.
doi:10.1007/978-3-319-17470-9_7 fatcat:lhmrsbzq3rcfxc4n5kty2o5rbq