A Degree Bound For The c-Boomerang Uniformity Of Permutation Monomials

Let ${\mathbb{F}}_q$ be a finite field of characteristic $p$. In this paper we prove that the $c$-Boomerang Uniformity, $c\mathrm{\ne }0$, for all permutation monomials $x^d$, where $d>1$ and $p\nmid d$, is bounded by $d^2$. Further, we utilize this bound to estimate the $c$-boomerang uniformity of a large class of Generalized Triangular Dynamical Systems, a polynomial-based approach to describe cryptographic permutations, including the well-known Substitution-Permutation Network.