X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/rairo15.git/blobdiff_plain/5e3dba6ade7cdb2d622eec1fd7d7ef5a0a168b4d..2644c7bc8564e7829d6f0d9b2e2a66e6460aec67:/prng.tex?ds=sidebyside diff --git a/prng.tex b/prng.tex index 88253cf..45fcfcd 100644 --- a/prng.tex +++ b/prng.tex @@ -1,6 +1,7 @@ Let us finally present the pseudorandom number generator $\chi_{\textit{15Rairo}}$ -which is based on random walks in $\Gamma(f)$. -More precisely, let be given a Boolean map $f:\Bool^n \rightarrow \Bool^n$, +which is based on random walks in $\Gamma_{\{b\}}(f)$. +More precisely, let be given a Boolean map $f:\Bool^{\mathsf{N}} \rightarrow +\Bool^\mathsf{N}$, a PRNG \textit{Random}, an integer $b$ that corresponds an iteration number (\textit{i.e.}, the length of the walk), and an initial configuration $x^0$. @@ -32,21 +33,22 @@ return $x$\; \end{algorithm} -This PRNG is a particularized version of Algorithm given in~\cite{DBLP:conf/secrypt/CouchotHGWB14}. +This PRNG is slightly different from $\chi_{\textit{14Secrypt}}$ +recalled in Algorithm~\ref{CI Algorithm}. As this latter, the length of the random walk of our algorithm is always constant (and is equal to $b$). However, in the current version, we add the constraint that the probability to execute the function $F_f$ is equal to 0.5 since the output of $\textit{Random(1)}$ is uniform in $\{0,1\}$. +This constraint is added to match the theoretical framework of +Sect.~\ref{sec:hypercube}. + + + +Notice that the chaos property of $G_f$ given in Sect.\ref{sec:proofOfChaos} +only requires that the graph $\Gamma_{\{b\}}(f)$ is strongly connected. +Since the $\chi_{\textit{15Rairo}}$ algorithme +only adds propbability constraints on existing edges, +it preserves this property. + -Let $f: \Bool^{n} \rightarrow \Bool^{n}$. -It has been shown~\cite[Th. 4, p. 135]{bcgr11:ip} that -if its iteration graph is strongly connected, then -the output of $\chi_{\textit{14Secrypt}}$ follows -a law that tends to the uniform distribution -if and only if its Markov matrix is a doubly stochastic matrix. - -Let us now present a method to -generate functions -with Doubly Stochastic matrix and Strongly Connected iteration graph, -denoted as DSSC matrix.