Построение линейных базисов векторных пространств над полем GF(2)

Пропонуються два алгоритми побудови лінійних базисів над простором GF(2)n. Перший алгоритм дозволяє здійснювати вибір з повної множини базисів над GF(2)n, але є відносно складним. Другий є значно простішим, але здійснює вибір не з повної множини.Two algorithms for building a linear basis over GF(2)n are proposed. The first one allows choosing a linear basis of the full space, but it is comparatively complicated. The second one is much easier, but it performs choosing from the truncated space

Revisiting some results on APN and algebraic immune functions

We push a little further the study of two characterizations of almost perfect nonlinear (APN) functions introduced in our recent monograph. We state open problems about them, and we revisit in their perspective a well-known result from Dobbertin on APN exponents. This leads us to new results about APN power functions and more general APN polynomials with coefficients in a subfield F_{2^k} , which ease the research of such functions and of differentially uniform functions, and simplifies the related proofs by avoiding tedious calculations. In a second part, we give slightly simpler proofs than in the same monograph, of two known results on Boolean functions, one of which deserves to be better known but needed clarification, and the other needed correction

On the Primary Constructions of Vectorial Boolean Bent Functions

Vectorial Boolean bent functions, which possess the maximal nonlinearity and the minimum differential uniformity, contribute to optimum resistance against linear cryptanalysis and differential cryptanalysis for the cryptographic algorithms that adopt them as nonlinear components. This paper is devoted to the new primary constructions of vectorial Boolean bent functions, including four types: vectorial monomial bent functions, vectorial Boolean bent functions with multiple trace terms, $\mathcal{H}$ vectorial functions and $\mathcal{H}$-like vectorial functions. For vectorial monomial bent functions, this paper answers one open problem proposed by E. Pasalic et al. and characterizes the vectorial monomial bent functions corresponding to the five known classes of bent exponents. For the vectorial Boolean bent functions with multiple trace terms, this paper answers one open problem proposed by A. Muratović-Ribić et al., presents six new infinite classes of explicit constructions and shows the nonexistence of the vectorial Boolean bent functions from $\mathbb{F}_{2^{n}}$ to $\mathbb{F}_{2^{k}}$ of the form $\sum_{i=1}^{2^{k-2}}Tr^{n}_{k}(ax^{(2i-1)(2^{k}-1)})$ with $n=2k$ and $a\in\mathbb{F}_{2^{k}}^{*}$. Moreover, $\mathcal{H}$ vectorial functions are further characterized. In addition, a new infinite class of vectorial Boolean bent function named as $\mathcal{H}$-like vectorial functions are derived, which includes $\mathcal{H}$ vectorial functions as a subclass