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The strength of cryptographic keys is an active challenge in academic research and industrial practice. In this paper we discuss the entropy as fundamentally important concept for generating hard-to-guess, i.e., strong, cryptographic keys and outline the difficulties in generating and estimating the available entropy for cryptographic needs. We consider traditional entropy estimation in cryptographic applications and motivate the development of new spectral techniques for estimation.
Vassilev, A.
and Hall, T.
(2014),
The Importance of Entropy to Information Security, Computer (IEEE Computer), [online], https://doi.org/10.1109/MC.2014.47
(Accessed October 9, 2025)