2 research outputs found
On values of vectorial Boolean functions and related problems in APN functions
In this paper we prove that there are only differential 4-uniform functions which are on distance 1 from an APN function. Also we prove that there are no APN functions of distance 1 from another APN functions up to dimension 5. We determine some properties of
the set of values of an arbitrary vectorial Boolean function from F_n^2 to F_n^2 in connection to the set of values of its derivatives. These results are connected to several open question concerning metric properties of APN functions
Problems, solutions and experience of the first international student\u27s Olympiad in cryptography
A detailed overview of the problems, solutions and experience of the
first international student\u27s Olympiad in cryptography,
NSUCRYPTO\u272014, is given. We start with rules of participation and
description of rounds. All 15 problems of the Olympiad and their
solutions are considered in detail. There are discussed solutions of
the mathematical problems related to cipher constructing such as
studying of differential characteristics of S-boxes, S-box masking,
determining of relations between cyclic rotation and additions
modulo and , constructing of special linear subspaces in
; problems about the number of solutions of the
equation over the finite field
and APN functions. Some unsolved problems in symmetric cryptography
are also considered