X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/16dcc.git/blobdiff_plain/e1fe6e435ee452003a7135763d26e2320756398c..79f46c777f6ef3202c2fb25194822518cad3e32c:/intro.tex?ds=sidebyside diff --git a/intro.tex b/intro.tex index df2a0ee..83b0a5a 100644 --- a/intro.tex +++ b/intro.tex @@ -1,5 +1,5 @@ The exploitation of chaotic systems to generate pseudorandom sequences -is an hot topic~\cite{915396,915385,5376454}. Such systems are +is a hot topic~\cite{915396,915385,5376454}. Such systems are fundamentally chosen due to their unpredictable character and their sensitiveness to initial conditions. In most cases, these generators simply consist in iterating a chaotic function like the logistic @@ -35,7 +35,7 @@ function (\textit{i.e.}, $f : \{0,1\}^{\mathsf{N}} \rightarrow \{0,1\}^{\mathsf{N}}$). These generators are $\textit{CIPRNG}_f^1(u)$ \cite{guyeuxTaiwan10,bcgr11:ip}, $\textit{CIPRNG}_f^2(u,v)$ -\cite{wbg10ip} and $\chi_{\textit{14Secrypt}}$ +\cite{wbg10ip}, and $\chi_{\textit{14Secrypt}}$ \cite{DBLP:conf/secrypt/CouchotHGWB14} where \textit{CI} means \emph{Chaotic Iterations}. We have firstly proven in~\cite{bcgr11:ip} that, to establish the chaotic nature of algorithm @@ -71,12 +71,12 @@ a doubly stochastic Markov matrix. However, the removed Hamiltonian cycle has a great influence in the quality of the output. -For instance, if this one one is not balanced (\textit{i.e.}, +For instance, if this one is not balanced (\textit{i.e.}, the number of changes in different bits are completely different), some bits would be hard to switch. This article shows an effective algorithm that efficiently implements the previous scheme and provides thus functions issued -from removing in the $\mathsf{N}$-cube a \emph{balanced} Hamiltonian cycle. +from removing, in the $\mathsf{N}$-cube, a \emph{balanced} Hamiltonian cycle. The length $b$ of the walk to reach a distribution close to the uniform one would be dramatically long. @@ -88,8 +88,9 @@ suite is evaluated. - -The remainder of this article is organized as follows. The next +This article, which +is an extension of~\cite{DBLP:conf/secrypt/CouchotHGWB14}, +is organized as follows. The next section is devoted to preliminaries, basic notations, and terminologies regarding Boolean map iterations. Then, in Section~\ref{sec:proofOfChaos}, Devaney's definition of chaos is @@ -99,15 +100,21 @@ Section~\ref{sec:SCCfunc} recalls a general scheme to obtain functions with awaited behavior. Main theorems are recalled to make the document self-content. The next section (Sect.~\ref{sec:hamilton}) presents an algorithm that -implements this scheme and proves it always produces a solution. -This is the second major contribution -The later section -(Sect.~\ref{sec:hypercube}) defines the theoretical framework to study -the mixing-time, \textit{i.e.}, time until reaching a uniform +implements this scheme and proves that it always produces a solution. +This is the second major contribution. +Then, Section~\ref{sec:hypercube} defines the theoretical framework to study +the mixing-time, \textit{i.e.}, time until reaching an uniform distribution. It proves that this one is at worth quadratic in the number -of elements. Experiments show that the bound is practically largely much -lower. This is the third major contribution. The +of elements. Experiments show that the bound is in practice largely much +lower. This is the third major contribution. Section~\ref{sec:prng} gives practical results on evaluating the PRNG against the NIST suite. This research work ends by a conclusion section, where the contribution is summarized and intended future work is outlined. + +%%% Local Variables: +%%% mode: latex +%%% TeX-master: "main" +%%% ispell-dictionary: "american" +%%% mode: flyspell +%%% End: