Open AccessRevisiting some results on APN and algebraic immune functions
Author(s) -
Claude Carlet
Publication year - 2023
Publication title -
advances in mathematics of communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 26
eISSN - 1930-5346
pISSN - 1930-5338
DOI - 10.3934/amc.2021035
Subject(s) - mathematics , boolean function , mathematical proof , construct (python library) , simple (philosophy) , function (biology) , algebraic number , nonlinear system , polynomial , discrete mathematics , pure mathematics , algebra over a field , mathematical analysis , computer science , philosophy , physics , geometry , epistemology , quantum mechanics , programming language , evolutionary biology , biology
We push a little further the study of two recent characterizations of almost perfect nonlinear (APN) functions. 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 a new result about APN power functions and more general APN polynomials with coefficients in a subfield \begin{document}$ \mathbb{F}_{2^k} $\end{document} , which eases the research of such functions. It also allows to construct automatically many differentially uniform functions from them (this avoids calculations for proving their differential uniformity as done in a recent paper, which are tedious and specific to each APN function). In a second part, we give simple proofs of two important results on Boolean functions, one of which deserves to be better known but needed clarification, while the other needed correction.