Showing papers on "Differential cryptanalysis published in 1987"

Introduction to cryptology

Abstract: Character sets and substitutions Transposition ciphers and transposed alphabets Cryptographic security Mathematically-based cryptology Congruencies and modular arithmetic Shifts, inverses and polyalphabets Prime numbers and multiplication inverses Logarithms and exponents Public key cryptosystems Polyalphabetical and auto-key ciphers Polygraphic ciphers Matrix ciphers Matrices and simultaneous equations The inherent flaw in linear ciphers Binary ciphers The data encryption standard Idiosyncratic cryptology.

The automated cryptanalysis of polyalphabetic ciphers

Abstract: This paper reports an extension of work published in 1986 by Carroll and Martin [1,2]. The earlier work automatically solved simple substitution ciphers in a cryptotext-only attack. It used a computer program written in the artificial intelligence language Prolog. The Prolog data base contained 1084 rules. The work reported here reduces the running time required to break simple substitution ciphers and breaks polyal-phabetic ciphers as well. Results suggest that the only inherent limitations on the ability to break ciphers as the number of crypto alphabets increases reside in the speed of computation and the availability of cryptotext.

Non-expanding, key-minimal, robustly-perfect, linear and bilinear ciphers

Abstract: The purposes of this paper are: (1) to give appropriate definitions of robustly-perfect ciphers, linear ciphers and bilinear ciphers: (2) to give two general constructions of robustly-perfect bilinear block ciphers that do not expand the plaintext and that have the smallest possible amount of secret key; (3) to give some isolated examples of robustly-perfect linear stream ciphers that use less key than had been earlier conjectured to be necessary; and (4) to suggest some possible useful applications for robustly-perfect linear and bilinear ciphers.