Title
Improved upper bound on root number of linearized polynomials and its application to nonlinearity estimation of Boolean functions.
Abstract
To determine the dimension of null space of any given linearized polynomial is one of vital problems in finite field theory, with concern to design of modern symmetric cryptosystems. But, the known general theory for this task is much far from giving the exact dimension when applied to a specific linearized polynomial. The first contribution of this paper is to give a better general method to get more precise upper bound on the root number of any given linearized polynomial. We anticipate this result would be applied as a useful tool in many research branches of finite field and cryptography. Really we apply this result to get tighter estimations of the lower bounds on the second order nonlinearities of general cubic Boolean functions, which has been being an active research problem during the past decade, with many examples showing great improvements. Furthermore, this paper shows that by studying the distribution of radicals of derivatives of a given Boolean functions one can get a better lower bound of the second-order nonlinearity, through an example of the monomial Boolean function $g_{mu}=Tr(mu x^{2^{2r}+2^r+1})$ over any finite field $GF{n}$.
Year
Venue
DocType
2018
IACR Cryptology ePrint Archive
Journal
Volume
Citations 
PageRank 
abs/1811.11280
0
0.34
References 
Authors
0
3
Name
Order
Citations
PageRank
Sihem Mesnager135566.14
Kwang Ho Kim22011.90
Myong Song Jo300.34