Merge remote-tracking branch 'upstream/master'

14 files changed, 1146 insertions, 1 deletions

diff --git a/buch/chapters/90-crypto/images/Makefile b/buch/chapters/90-crypto/images/Makefile
index 9480163..f4bed14 100644
--- a/buch/chapters/90-crypto/images/Makefile
+++ b/buch/chapters/90-crypto/images/Makefile
@@ -3,7 +3,8 @@
 #
 # (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
 #
-all:	dh.pdf elliptic.pdf
+all:	dh.pdf elliptic.pdf schieberegister.pdf multiplikation.pdf sbox.pdf \
+	shift.pdf keys.pdf
 
 dh.pdf:	dh.tex
 	pdflatex dh.tex
@@ -11,3 +12,18 @@ dh.pdf:	dh.tex
 elliptic.pdf:	elliptic.tex
 	pdflatex elliptic.tex
 
+schieberegister.pdf:	schieberegister.tex
+	pdflatex schieberegister.tex
+
+multiplikation.pdf:	multiplikation.tex
+	pdflatex multiplikation.tex
+
+sbox.pdf:	sbox.tex
+	pdflatex sbox.tex
+
+shift.pdf:	shift.tex
+	pdflatex shift.tex
+
+keys.pdf:	keys.tex
+	pdflatex keys.tex
+
diff --git a/buch/chapters/90-crypto/images/dh.pdf b/buch/chapters/90-crypto/images/dh.pdf
index 67b95a5..eede4bd 100644
--- a/buch/chapters/90-crypto/images/dh.pdf
+++ b/buch/chapters/90-crypto/images/dh.pdf
diff --git a/buch/chapters/90-crypto/images/elliptic.pdf b/buch/chapters/90-crypto/images/elliptic.pdf
index d408f1e..e58639f 100644
--- a/buch/chapters/90-crypto/images/elliptic.pdf
+++ b/buch/chapters/90-crypto/images/elliptic.pdf
diff --git a/buch/chapters/90-crypto/images/keys.pdf b/buch/chapters/90-crypto/images/keys.pdf
new file mode 100644
index 0000000..2c6b4b9
--- /dev/null
+++ b/buch/chapters/90-crypto/images/keys.pdf
diff --git a/buch/chapters/90-crypto/images/keys.tex b/buch/chapters/90-crypto/images/keys.tex
new file mode 100644
index 0000000..d556b7c
--- /dev/null
+++ b/buch/chapters/90-crypto/images/keys.tex
@@ -0,0 +1,121 @@
+%
+% keys.tex -- template for standalon tikz images
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\documentclass[tikz]{standalone}
+\usepackage{amsmath}
+\usepackage{times}
+\usepackage{txfonts}
+\usepackage{pgfplots}
+\usepackage{csvsimple}
+\usetikzlibrary{arrows,intersections,math}
+\begin{document}
+\def\skala{1}
+\begin{tikzpicture}[>=latex,thick,scale=\skala]
+\definecolor{darkgreen}{rgb}{0,0.6,0}
+\def\s{0.5}
+\def\punkt#1#2{({(#1)*\s},{(#2)*\s})}
+\def\wort#1#2#3{
+	\fill[color=#3] \punkt{#1}{#2} rectangle \punkt{(#1+1)}{(#2+4)};
+	\draw \punkt{#1}{#2} rectangle \punkt{(#1+1)}{(#2+4)};
+}
+
+\def\summe{
+	\foreach \x in {0,3,...,21}{
+		\draw[->] \punkt{(\x+0.5)}{-0.1} -- \punkt{(\x+0.5)}{-2.1};
+		\draw \punkt{(\x+0.5)}{-2.5} circle[radius={0.3*\s}];
+		\draw \punkt{(\x+0.5-0.2)}{-2.5} 
+			--
+			\punkt{(\x+0.5+0.2)}{-2.5};
+		\draw \punkt{(\x+0.5)}{-2.5+0.2} 
+			--
+			\punkt{(\x+0.5)}{-2.5-0.2};
+		\draw[->] \punkt{(\x+0.5)}{-2.9} -- \punkt{(\x+0.5)}{-4.9};
+	}
+	\foreach \x in {0,3,...,18}{
+		\draw[->] \punkt{(\x+1.1)}{-7} -- \punkt{(\x+2)}{-7}
+			-- \punkt{(\x+2)}{-2.5} -- \punkt{(\x+3.1)}{-2.5};
+	}
+	\fill[color=white]
+		\punkt{(9+1.25)}{-5.5}
+		rectangle
+		\punkt{(9+2.75)}{-4.00};
+	\draw
+		\punkt{(9+1.25)}{-5.5}
+		rectangle
+		\punkt{(9+2.75)}{-4.00};
+	\node at \punkt{(9+2)}{-4.75} {$S$};
+}
+
+\def\blocks#1{
+	\foreach \x in {0,3,...,21}{
+		\wort{\x}{0}{#1}
+	}
+}
+
+\def\schlange#1{
+	\draw[->] \punkt{22.1}{2} -- \punkt{23}{2}
+		-- \punkt{23}{-1.0} -- \punkt{-3}{-1.0}
+		-- \punkt{-3}{-8} -- \punkt{-1}{-8} -- \punkt{-1}{-2.5}
+		-- \punkt{0.1}{-2.5};
+	;
+	\fill[color=white] \punkt{-3.75}{-1.75} rectangle \punkt{-2.25}{-3.25};
+	\draw \punkt{-3.75}{-1.75} rectangle \punkt{-2.25}{-3.25};
+	\node at \punkt{-3}{-2.5} {$\pi$};
+
+	\fill[color=white] \punkt{-3.75}{-3.75} rectangle \punkt{-2.25}{-5.25};
+	\draw \punkt{-3.75}{-3.75} rectangle \punkt{-2.25}{-5.25};
+	\node at \punkt{-3}{-4.5} {$S$};
+
+	\fill[color=white] \punkt{-3.75}{-5.75} rectangle \punkt{-2.25}{-7.25};
+	\draw \punkt{-3.75}{-5.75} rectangle \punkt{-2.25}{-7.25};
+	\node at \punkt{-3}{-6.5} {$r_{#1}$};
+}
+
+\begin{scope}
+	\blocks{blue!20}
+	\foreach \x in {0,...,7}{
+		\node at \punkt{(3*\x+0.5)}{2} {$K_\x$};
+	}
+	\schlange{1}
+	\summe
+\end{scope}
+
+\begin{scope}[yshift=-4.5cm]
+	\blocks{darkgreen!20}
+	\foreach \x in {8,...,15}{
+		\node at \punkt{(3*(\x-8)+0.5)}{2} {$K_{\x}$};
+	}
+	\schlange{2}
+	\summe
+\end{scope}
+
+\begin{scope}[yshift=-9cm]
+	\blocks{darkgreen!20}
+	\foreach \x in {16,...,23}{
+		\node at \punkt{(3*(\x-16)+0.5)}{2} {$K_{\x}$};
+	}
+	\schlange{3}
+	\summe
+\end{scope}
+
+\begin{scope}[yshift=-13.5cm]
+	\blocks{darkgreen!20}
+	\foreach \x in {24,...,31}{
+		\node at \punkt{(3*(\x-24)+0.5)}{2} {$K_{\x}$};
+	}
+	\foreach \x in {0,3,...,21}{
+		\draw[->,color=gray]
+			\punkt{(\x+0.5)}{-0.1} -- \punkt{(\x+0.5)}{-2.1};
+		\node[color=gray] at \punkt{(\x+0.5)}{-2.1} [below] {$\vdots$};
+	}
+	\draw[color=gray] \punkt{22.1}{2} -- \punkt{23}{2}
+		-- \punkt{23}{-1.0} -- \punkt{-3}{-1.0}
+		-- \punkt{-3}{-2.1};
+	\node[color=gray] at \punkt{-3}{-2.1} [below] {$\vdots$};
+\end{scope}
+
+\end{tikzpicture}
+\end{document}
+
diff --git a/buch/chapters/90-crypto/images/multiplikation.pdf b/buch/chapters/90-crypto/images/multiplikation.pdf
new file mode 100644
index 0000000..86345b8
--- /dev/null
+++ b/buch/chapters/90-crypto/images/multiplikation.pdf
diff --git a/buch/chapters/90-crypto/images/multiplikation.tex b/buch/chapters/90-crypto/images/multiplikation.tex
new file mode 100644
index 0000000..27c4329
--- /dev/null
+++ b/buch/chapters/90-crypto/images/multiplikation.tex
@@ -0,0 +1,464 @@
+%
+% multiplikation.tex -- 
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\documentclass[tikz]{standalone}
+\usepackage{amsmath}
+\usepackage{times}
+\usepackage{txfonts}
+\usepackage{pgfplots}
+\usepackage{csvsimple}
+\usetikzlibrary{arrows,intersections,math}
+\begin{document}
+\def\skala{1}
+\begin{tikzpicture}[>=latex,thick,scale=\skala]
+
+\definecolor{darkgreen}{rgb}{0,0.6,0}
+
+\def\s{0.45}
+
+\def\punkt#1#2{({#1*\s},{#2*\s})}
+
+\def\pfeile{
+	\foreach \x in {0.5,1.5,...,7.5}{
+		\draw[->,color=blue] \punkt{\x}{-2.1} -- \punkt{(\x-1)}{-3.3};
+	}
+}
+
+\begin{scope}[yshift=0.1cm]
+	\node at \punkt{0}{0.5} [left] {$p(X)=\mathstrut$};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node at \punkt{0.5}{0.5} {\texttt{1}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{0}};
+	\node at \punkt{3.5}{0.5} {\texttt{1}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{1}};
+	\foreach \x in {0.5,1.5,...,7.5}{
+		\draw[->,color=blue] \punkt{\x}{-0.1} -- \punkt{(\x-1)}{-1.3};
+	}
+\end{scope}
+
+\begin{scope}[yshift=-1cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{1}};
+	\node at \punkt{0.5}{0.5} {\texttt{0}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{0}};
+	\node at \punkt{4.5}{0.5} {\texttt{1}};
+	\node at \punkt{5.5}{0.5} {\texttt{0}};
+	\node at \punkt{6.5}{0.5} {\texttt{1}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+	\draw[->,color=darkgreen]
+		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{0}};
+	\node at \punkt{1.5}{-1.5} {\texttt{0}};
+	\node at \punkt{2.5}{-1.5} {\texttt{1}};
+	\node at \punkt{3.5}{-1.5} {\texttt{1}};
+	\node at \punkt{4.5}{-1.5} {\texttt{0}};
+	\node at \punkt{5.5}{-1.5} {\texttt{0}};
+	\node at \punkt{6.5}{-1.5} {\texttt{0}};
+	\node at \punkt{7.5}{-1.5} {\texttt{1}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-3cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{0}};
+	\node at \punkt{0.5}{0.5} {\texttt{0}};
+	\node at \punkt{1.5}{0.5} {\texttt{1}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{0}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{0}};
+	\node at \punkt{6.5}{0.5} {\texttt{1}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+%	\draw[->,color=darkgreen]
+%		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+%	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{0}};
+	\node at \punkt{1.5}{-1.5} {\texttt{1}};
+	\node at \punkt{2.5}{-1.5} {\texttt{1}};
+	\node at \punkt{3.5}{-1.5} {\texttt{0}};
+	\node at \punkt{4.5}{-1.5} {\texttt{0}};
+	\node at \punkt{5.5}{-1.5} {\texttt{0}};
+	\node at \punkt{6.5}{-1.5} {\texttt{1}};
+	\node at \punkt{7.5}{-1.5} {\texttt{0}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-5cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{0}};
+	\node at \punkt{0.5}{0.5} {\texttt{1}};
+	\node at \punkt{1.5}{0.5} {\texttt{1}};
+	\node at \punkt{2.5}{0.5} {\texttt{0}};
+	\node at \punkt{3.5}{0.5} {\texttt{0}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+%	\draw[->,color=darkgreen]
+%		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+%	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{1}};
+	\node at \punkt{1.5}{-1.5} {\texttt{1}};
+	\node at \punkt{2.5}{-1.5} {\texttt{0}};
+	\node at \punkt{3.5}{-1.5} {\texttt{0}};
+	\node at \punkt{4.5}{-1.5} {\texttt{0}};
+	\node at \punkt{5.5}{-1.5} {\texttt{1}};
+	\node at \punkt{6.5}{-1.5} {\texttt{0}};
+	\node at \punkt{7.5}{-1.5} {\texttt{0}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-7cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{1}};
+	\node at \punkt{0.5}{0.5} {\texttt{1}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{0}};
+	\node at \punkt{3.5}{0.5} {\texttt{0}};
+	\node at \punkt{4.5}{0.5} {\texttt{1}};
+	\node at \punkt{5.5}{0.5} {\texttt{0}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+	\draw[->,color=darkgreen]
+		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{1}};
+	\node at \punkt{1.5}{-1.5} {\texttt{0}};
+	\node at \punkt{2.5}{-1.5} {\texttt{0}};
+	\node at \punkt{3.5}{-1.5} {\texttt{1}};
+	\node at \punkt{4.5}{-1.5} {\texttt{0}};
+	\node at \punkt{5.5}{-1.5} {\texttt{0}};
+	\node at \punkt{6.5}{-1.5} {\texttt{1}};
+	\node at \punkt{7.5}{-1.5} {\texttt{1}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-9cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{1}};
+	\node at \punkt{0.5}{0.5} {\texttt{0}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{0}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{1}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+	\draw[->,color=darkgreen]
+		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{0}};
+	\node at \punkt{1.5}{-1.5} {\texttt{0}};
+	\node at \punkt{2.5}{-1.5} {\texttt{1}};
+	\node at \punkt{3.5}{-1.5} {\texttt{1}};
+	\node at \punkt{4.5}{-1.5} {\texttt{1}};
+	\node at \punkt{5.5}{-1.5} {\texttt{1}};
+	\node at \punkt{6.5}{-1.5} {\texttt{0}};
+	\node at \punkt{7.5}{-1.5} {\texttt{1}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-11cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{0}};
+	\node at \punkt{0.5}{0.5} {\texttt{0}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{1}};
+	\node at \punkt{4.5}{0.5} {\texttt{1}};
+	\node at \punkt{5.5}{0.5} {\texttt{0}};
+	\node at \punkt{6.5}{0.5} {\texttt{1}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+%	\draw[->,color=darkgreen]
+%		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+%	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{0}};
+	\node at \punkt{1.5}{-1.5} {\texttt{0}};
+	\node at \punkt{2.5}{-1.5} {\texttt{1}};
+	\node at \punkt{3.5}{-1.5} {\texttt{1}};
+	\node at \punkt{4.5}{-1.5} {\texttt{1}};
+	\node at \punkt{5.5}{-1.5} {\texttt{0}};
+	\node at \punkt{6.5}{-1.5} {\texttt{1}};
+	\node at \punkt{7.5}{-1.5} {\texttt{0}};
+
+	\pfeile
+\end{scope}
+
+\begin{scope}[yshift=-13cm]
+	\draw[<-] \punkt{8.2}{-1.3} arc (-30:30:1.8);
+	\node at \punkt{9.3}{0.6} {$\mathstrut\cdot X$};
+	\fill[color=blue!20] \punkt{-1}{0} rectangle \punkt{0}{1};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node[color=darkgreen] at \punkt{-0.5}{0.5} {\texttt{0}};
+	\node at \punkt{0.5}{0.5} {\texttt{0}};
+	\node at \punkt{1.5}{0.5} {\texttt{1}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{1}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{0}};
+
+%	\draw[->,color=darkgreen]
+%		\punkt{-0.5}{0.1} -- \punkt{-0.5}{-0.5} -- \punkt{3.1}{-0.5};
+%	\node[color=darkgreen] at \punkt{3.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{4.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{6.5}{-0.5} {\texttt{1}};
+%	\node[color=darkgreen] at \punkt{7.5}{-0.5} {\texttt{1}};
+	\node[color=darkgreen] at \punkt{4}{-0.5} {$\|$};
+
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+	\node at \punkt{0.5}{-1.5} {\texttt{0}};
+	\node at \punkt{1.5}{-1.5} {\texttt{1}};
+	\node at \punkt{2.5}{-1.5} {\texttt{1}};
+	\node at \punkt{3.5}{-1.5} {\texttt{0}};
+	\node at \punkt{4.5}{-1.5} {\texttt{1}};
+	\node at \punkt{5.5}{-1.5} {\texttt{1}};
+	\node at \punkt{6.5}{-1.5} {\texttt{1}};
+	\node at \punkt{7.5}{-1.5} {\texttt{1}};
+
+%	\pfeile
+\end{scope}
+
+\begin{scope}[xshift=9cm]
+
+\begin{scope}[yshift=0.1cm]
+	\draw[->] \punkt{-11.8}{0.5} -- \punkt{-0.1}{0.5};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\draw \punkt{4}{-0.1} -- \punkt{4}{-3};
+	\node at \punkt{0.5}{0.5} {\texttt{1}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{0}};
+	\node at \punkt{3.5}{0.5} {\texttt{1}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{1}};
+\end{scope}
+
+\def\summation#1#2#3#4#5#6#7#8{
+	\draw[->] \punkt{4}{2.3} -- \punkt{4}{1};
+
+	\draw[->] \punkt{-11.8}{0.5} -- \punkt{3.5}{0.5};
+
+	\draw \punkt{4}{0.5} circle[radius=0.2];
+	\draw \punkt{4}{0.20} -- \punkt{4}{0.80};
+	\draw \punkt{3.7}{0.5} -- \punkt{4.3}{0.5};
+
+	\draw[->] \punkt{4}{-0.05} -- \punkt{4}{-0.95};
+	\draw \punkt{0}{-2} rectangle \punkt{8}{-1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{-2} -- \punkt{\x}{-1};
+	}
+
+	\node at \punkt{0.5}{-1.5} {\texttt{#1}};
+	\node at \punkt{1.5}{-1.5} {\texttt{#2}};
+	\node at \punkt{2.5}{-1.5} {\texttt{#3}};
+	\node at \punkt{3.5}{-1.5} {\texttt{#4}};
+	\node at \punkt{4.5}{-1.5} {\texttt{#5}};
+	\node at \punkt{5.5}{-1.5} {\texttt{#6}};
+	\node at \punkt{6.5}{-1.5} {\texttt{#7}};
+	\node at \punkt{7.5}{-1.5} {\texttt{#8}};
+}
+
+\begin{scope}[yshift=-1.9cm]
+	\summation{1}{0}{0}{1}{0}{1}{0}{1}
+\end{scope}
+
+\begin{scope}[yshift=-3.9cm]
+	\summation{1}{1}{1}{1}{0}{1}{1}{1}
+\end{scope}
+
+\begin{scope}[yshift=-5.9cm]
+	\summation{1}{1}{1}{1}{0}{1}{1}{1}
+\end{scope}
+
+\begin{scope}[yshift=-7.9cm]
+	\summation{0}{1}{1}{0}{0}{1}{0}{0}
+\end{scope}
+
+\begin{scope}[yshift=-9.9cm]
+	\summation{0}{1}{0}{1}{1}{0}{0}{1}
+\end{scope}
+
+\begin{scope}[yshift=-11.9cm]
+	\summation{0}{1}{0}{1}{1}{0}{0}{1}
+\end{scope}
+
+\begin{scope}[yshift=-13.9cm]
+	\summation{0}{0}{1}{1}{0}{1}{1}{0}
+	\node at \punkt{0}{-1.5} [left] {$p(X)\cdot q(X)=\mathstrut$};
+\end{scope}
+
+\end{scope}
+
+\begin{scope}[xshift=5cm]
+
+\begin{scope}[yshift=2cm]
+	\node at \punkt{0}{0.5} [left] {$q(X)=\mathstrut$};
+	\draw \punkt{0}{0} rectangle \punkt{8}{1};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{1};
+	}
+	\node at \punkt{0.5}{0.5} {\texttt{1}};
+	\node at \punkt{1.5}{0.5} {\texttt{0}};
+	\node at \punkt{2.5}{0.5} {\texttt{1}};
+	\node at \punkt{3.5}{0.5} {\texttt{1}};
+	\node at \punkt{4.5}{0.5} {\texttt{0}};
+	\node at \punkt{5.5}{0.5} {\texttt{1}};
+	\node at \punkt{6.5}{0.5} {\texttt{0}};
+	\node at \punkt{7.5}{0.5} {\texttt{1}};
+
+	\draw[->] \punkt{7.5}{-0.1} -- ({7.5*\s},{-1.3});
+	\node at ({7.5*\s},{-1.2}) [below] {$\mathstrut\cdot\texttt{1}$};
+
+	\def\y{1.2}
+
+	\draw[->] \punkt{6.5}{-0.1} -- ({6.5*\s},{-1*2-\y-0.1});
+	\node at ({6.5*\s},{-1*2-\y}) [below] {$\mathstrut\cdot\texttt{0}$};
+
+	\draw[->] \punkt{5.5}{-0.1} -- ({5.5*\s},{-2*2-\y-0.1});
+	\node at ({5.5*\s},{-2*2-\y}) [below] {$\mathstrut\cdot\texttt{1}$};
+
+	\draw[->] \punkt{4.5}{-0.1} -- ({4.5*\s},{-3*2-\y-0.1});
+	\node at ({4.5*\s},{-3*2-\y}) [below] {$\mathstrut\cdot\texttt{0}$};
+
+	\draw[->] \punkt{3.5}{-0.1} -- ({3.5*\s},{-4*2-\y-0.1});
+	\node at ({3.5*\s},{-4*2-\y}) [below] {$\mathstrut\cdot\texttt{1}$};
+
+	\draw[->] \punkt{2.5}{-0.1} -- ({2.5*\s},{-5*2-\y-0.1});
+	\node at ({2.5*\s},{-5*2-\y}) [below] {$\mathstrut\cdot\texttt{1}$};
+
+	\draw[->] \punkt{1.5}{-0.1} -- ({1.5*\s},{-6*2-\y-0.1});
+	\node at ({1.5*\s},{-6*2-\y}) [below] {$\mathstrut\cdot\texttt{0}$};
+
+	\draw[->] \punkt{0.5}{-0.1} -- ({0.5*\s},{-7*2-\y-0.1});
+	\node at ({0.5*\s},{-7*2-\y}) [below] {$\mathstrut\cdot\texttt{1}$};
+\end{scope}
+
+\end{scope}
+
+\end{tikzpicture}
+\end{document}
+
diff --git a/buch/chapters/90-crypto/images/sbox.m b/buch/chapters/90-crypto/images/sbox.m
new file mode 100644
index 0000000..973ffc9
--- /dev/null
+++ b/buch/chapters/90-crypto/images/sbox.m
@@ -0,0 +1,52 @@
+#
+# sbox.m
+#
+# (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+#
+A=[
+1,0,0,0,1,1,1,1;
+1,1,0,0,0,1,1,1;
+1,1,1,0,0,0,1,1;
+1,1,1,1,0,0,0,1;
+1,1,1,1,1,0,0,0;
+0,1,1,1,1,1,0,0;
+0,0,1,1,1,1,1,0;
+0,0,0,1,1,1,1,1;
+]
+
+R = zeros(8,16);
+R(:,1:8) = A;
+R(:,9:16) = eye(8);
+
+for k = (1:5)
+	for i=(k+1:8)
+		pivot = R(i,k);
+		R(i,:) = R(i,:) + pivot * R(k,:);
+	end
+	R = mod(R, 2)
+end
+
+P = [
+1,0,0,0,0,0,0,0;
+0,1,0,0,0,0,0,0;
+0,0,1,0,0,0,0,0;
+0,0,0,1,0,0,0,0;
+0,0,0,0,1,0,0,0;
+0,0,0,0,0,0,0,1;
+0,0,0,0,0,1,0,0;
+0,0,0,0,0,0,1,0;
+]
+
+R = P * R
+
+for k = (8:-1:2)
+	for i = (1:k-1)
+		pivot = R(i,k);
+		R(i,:) = R(i,:) + pivot * R(k,:);
+	end
+	R = mod(R, 2)
+end
+
+B = R(:,9:16)
+
+A * B
diff --git a/buch/chapters/90-crypto/images/sbox.pdf b/buch/chapters/90-crypto/images/sbox.pdf
new file mode 100644
index 0000000..7a5bdf3
--- /dev/null
+++ b/buch/chapters/90-crypto/images/sbox.pdf
diff --git a/buch/chapters/90-crypto/images/sbox.tex b/buch/chapters/90-crypto/images/sbox.tex
new file mode 100644
index 0000000..41f8812
--- /dev/null
+++ b/buch/chapters/90-crypto/images/sbox.tex
@@ -0,0 +1,241 @@
+%
+% sbox.tex -- template for standalon tikz images
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\documentclass[tikz]{standalone}
+\usepackage{amsmath}
+\usepackage{times}
+\usepackage{txfonts}
+\usepackage{pgfplots}
+\usepackage{csvsimple}
+\usetikzlibrary{arrows,intersections,math}
+\begin{document}
+\def\skala{1}
+\begin{tikzpicture}[>=latex,thick,scale=\skala]
+
+\def\s{0.2}
+\def\punkt#1#2{({#1*\s},{(8-(#2))*\s})}
+
+\definecolor{b}{rgb}{0,0,0}
+\definecolor{w}{rgb}{1,1,1}
+
+\def\feld#1#2#3{
+	\fill[color=#3] \punkt{#1}{#2} rectangle \punkt{(#1+1)}{(#2-1)};
+}
+
+\def\zeile#1#2#3#4#5#6#7#8#9{
+	\feld{0}{#1}{#2}
+	\feld{1}{#1}{#3}
+	\feld{2}{#1}{#4}
+	\feld{3}{#1}{#5}
+	\feld{4}{#1}{#6}
+	\feld{5}{#1}{#7}
+	\feld{6}{#1}{#8}
+	\feld{7}{#1}{#9}
+}
+\def\inverse#1#2#3#4#5#6#7#8#9{
+	\feld{8}{#1}{#2}
+	\feld{9}{#1}{#3}
+	\feld{10}{#1}{#4}
+	\feld{11}{#1}{#5}
+	\feld{12}{#1}{#6}
+	\feld{13}{#1}{#7}
+	\feld{14}{#1}{#8}
+	\feld{15}{#1}{#9}
+}
+\def\rechteck{
+	\draw (0,{1*\s}) rectangle ({16*\s},{(8+1)*\s});
+	\draw ({8*\s},{1*\s}) -- ({8*\s},{(8+1)*\s});
+}
+
+\def\pivot#1#2{
+	\draw[color=red,line width=1.2pt]
+		\punkt{(#1+\inset)}{(#2-\inset)}
+		rectangle
+		\punkt{(#1+1-\inset)}{(#2-1+\inset)};
+}
+\def\inset{0.1}
+\def\cleanup#1#2#3{
+	\pgfmathparse{(#3-#2)/abs(#3-#2)}
+	\xdef\signum{\pgfmathresult}
+	\draw[color=blue!50,line width=1.2pt]
+		\punkt{(#1+\inset)}{#3}
+		--
+		\punkt{(#1+\inset)}{(#2-1+\inset*\signum)}
+		--
+		\punkt{(#1+1-\inset)}{(#2-1+\inset*\signum)}
+		--
+		\punkt{(#1+1-\inset)}{#3}
+	;
+}
+
+\begin{scope}
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1bbwwwbbb \inverse1wbwwwwww
+	\zeile2bbbwwwbb \inverse2wwbwwwww
+	\zeile3bbbbwwwb \inverse3wwwbwwww
+	\zeile4bbbbbwww \inverse4wwwwbwww
+	\zeile5wbbbbbww \inverse5wwwwwbww
+	\zeile6wwbbbbbw \inverse6wwwwwwbw
+	\zeile7wwwbbbbb \inverse7wwwwwwwb
+	\rechteck
+	\pivot{0}{0}
+	\cleanup{0}{1}{7}
+\end{scope}
+
+\begin{scope}[xshift=4cm]
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wbbwbbww \inverse2bwbwwwww
+	\zeile3wbbbbbbw \inverse3bwwbwwww
+	\zeile4wbbbwbbb \inverse4bwwwbwww
+	\zeile5wbbbbbww \inverse5wwwwwbww
+	\zeile6wwbbbbbw \inverse6wwwwwwbw
+	\zeile7wwwbbbbb \inverse7wwwwwwwb
+	\rechteck
+	\pivot{1}{1}
+	\cleanup{1}{2}{7}
+\end{scope}
+
+\begin{scope}[xshift=8cm]
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwbbwbbw \inverse3wbwbwwww
+	\zeile4wwbbbbbb \inverse4wbwwbwww
+	\zeile5wwbbwbww \inverse5bbwwwbww
+	\zeile6wwbbbbbw \inverse6wwwwwwbw
+	\zeile7wwwbbbbb \inverse7wwwwwwwb
+	\rechteck
+	\pivot{2}{2}
+	\cleanup{2}{3}{7}
+\end{scope}
+
+\begin{scope}[xshift=12cm,yshift=0cm]
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwbw \inverse3wwbbwwww
+	\zeile4wwwbbwbb \inverse4wwbwbwww
+	\zeile5wwwbwwww \inverse5bwbwwbww
+	\zeile6wwwbbwbw \inverse6wbbwwwbw
+	\zeile7wwwbbbbb \inverse7wwwwwwwb
+	\rechteck
+	\pivot{3}{3}
+	\cleanup{3}{4}{7}
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{8}{7} -- \punkt{8}{11};
+\end{scope}
+
+\begin{scope}[xshift=12cm,yshift=-2.4cm]
+	\draw[<-,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwbw \inverse3wwbbwwww
+	\zeile4wwwwbwwb \inverse4wwwbbwww
+	\zeile5wwwwwwbw \inverse5bwwbwbww
+	\zeile6wwwwbwww \inverse6wbwbwwbw
+	\zeile7wwwwbbwb \inverse7wwbbwwwb
+	\rechteck
+	\pivot{4}{4}
+	\cleanup{4}{5}{7}
+\end{scope}
+
+\begin{scope}[xshift=8cm,yshift=-2.4cm]
+	\draw[<-,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwbw \inverse3wwbbwwww
+	\zeile4wwwwbwwb \inverse4wwwbbwww
+	\zeile5wwwwwwbw \inverse5bwwbwbww
+	\zeile6wwwwwwwb \inverse6wbwwbwbw
+	\zeile7wwwwwbww \inverse7wwbwbwwb
+	\rechteck
+\end{scope}
+
+\begin{scope}[xshift=4cm,yshift=-2.4cm]
+	\draw[<-,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbbbb \inverse0bwwwwwww
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwbw \inverse3wwbbwwww
+	\zeile4wwwwbwwb \inverse4wwwbbwww
+	\zeile5wwwwwbww \inverse5wwbwbwwb
+	\zeile6wwwwwwbw \inverse6bwwbwbww
+	\zeile7wwwwwwwb \inverse7wbwwbwbw
+	\rechteck
+	\cleanup{7}{7}{-1}
+\end{scope}
+
+\begin{scope}[xshift=0cm,yshift=-2.4cm]
+	\zeile0bwwwbbbw \inverse0bbwwbwbw
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwbw \inverse3wwbbwwww
+	\zeile4wwwwbwww \inverse4wbwbwwbw
+	\zeile5wwwwwbww \inverse5wwbwbwwb
+	\zeile6wwwwwwbw \inverse6bwwbwbww
+	\zeile7wwwwwwwb \inverse7wbwwbwbw
+	\rechteck
+	\cleanup{6}{6}{-1}
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{8}{7} -- \punkt{8}{11};
+\end{scope}
+
+\begin{scope}[xshift=0cm,yshift=-4.8cm]
+	\zeile0bwwwbbww \inverse0wbwbbbbw
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwbww \inverse2wbbwwwww
+	\zeile3wwwbwwww \inverse3bwbwwbww
+	\zeile4wwwwbwww \inverse4wbwbwwbw
+	\zeile5wwwwwbww \inverse5wwbwbwwb
+	\zeile6wwwwwwbw \inverse6bwwbwbww
+	\zeile7wwwwwwwb \inverse7wbwwbwbw
+	\rechteck
+	\cleanup{5}{5}{-1}
+\end{scope}
+
+\begin{scope}[xshift=4cm,yshift=-4.8cm]
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwbwww \inverse0wbbbwbbb
+	\zeile1wbwwbwww \inverse1bbwwwwww
+	\zeile2wwbwwwww \inverse2wbwwbwwb
+	\zeile3wwwbwwww \inverse3bwbwwbww
+	\zeile4wwwwbwww \inverse4wbwbwwbw
+	\zeile5wwwwwbww \inverse5wwbwbwwb
+	\zeile6wwwwwwbw \inverse6bwwbwbww
+	\zeile7wwwwwwwb \inverse7wbwwbwbw
+	\rechteck
+	\cleanup{4}{4}{-1}
+\end{scope}
+
+\begin{scope}[xshift=8cm,yshift=-4.8cm]
+	\draw[->,shorten >= 0.05cm,shorten <= 0.05cm]
+		\punkt{-4}{3} -- \punkt{0}{3};
+	\zeile0bwwwwwww \inverse0wwbwwbwb
+	\zeile1wbwwwwww \inverse1bwwbwwbw
+	\zeile2wwbwwwww \inverse2wbwwbwwb
+	\zeile3wwwbwwww \inverse3bwbwwbww
+	\zeile4wwwwbwww \inverse4wbwbwwbw
+	\zeile5wwwwwbww \inverse5wwbwbwwb
+	\zeile6wwwwwwbw \inverse6bwwbwbww
+	\zeile7wwwwwwwb \inverse7wbwwbwbw
+	\rechteck
+\end{scope}
+
+\end{tikzpicture}
+\end{document}
+
diff --git a/buch/chapters/90-crypto/images/schieberegister.pdf b/buch/chapters/90-crypto/images/schieberegister.pdf
new file mode 100644
index 0000000..30b675b
--- /dev/null
+++ b/buch/chapters/90-crypto/images/schieberegister.pdf
diff --git a/buch/chapters/90-crypto/images/schieberegister.tex b/buch/chapters/90-crypto/images/schieberegister.tex
new file mode 100644
index 0000000..7c24e52
--- /dev/null
+++ b/buch/chapters/90-crypto/images/schieberegister.tex
@@ -0,0 +1,120 @@
+%
+% schieberegister.tex -- template for standalon tikz images
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\documentclass[tikz]{standalone}
+\usepackage{amsmath}
+\usepackage{times}
+\usepackage{txfonts}
+\usepackage{pgfplots}
+\usepackage{csvsimple}
+\usetikzlibrary{arrows,intersections,math}
+\begin{document}
+\def\skala{1}
+\begin{tikzpicture}[>=latex,thick,scale=\skala]
+
+\definecolor{darkgreen}{rgb}{0,0.6,0}
+
+\def\s{0.8}
+
+\def\punkt#1#2{({#1*\s},{#2*\s})}
+
+\fill[color=blue!20] \punkt{0}{0} rectangle \punkt{8}{1};
+
+\node at \punkt{0.5}{1} [above] {$X^7\mathstrut$};
+\node at \punkt{3}{1}   [above] {$+\mathstrut$};
+\node at \punkt{3.5}{1} [above] {$X^4\mathstrut$};
+\node at \punkt{5}{1}   [above] {$+\mathstrut$};
+\node at \punkt{5.5}{1} [above] {$X^2\mathstrut$};
+\node at \punkt{7}{1}   [above] {$+\mathstrut$};
+\node at \punkt{7.5}{1} [above] {$1\mathstrut$};
+
+\node at \punkt{0}{1} [above left] {\llap{$p(X)=\mathstrut$}};
+
+\node at \punkt{0.5}{0.5} {\texttt{1}};
+\node at \punkt{1.5}{0.5} {\texttt{0}};
+\node at \punkt{2.5}{0.5} {\texttt{0}};
+\node at \punkt{3.5}{0.5} {\texttt{1}};
+\node at \punkt{4.5}{0.5} {\texttt{0}};
+\node at \punkt{5.5}{0.5} {\texttt{1}};
+\node at \punkt{6.5}{0.5} {\texttt{0}};
+\node at \punkt{7.5}{0.5} {\texttt{1}};
+
+\draw \punkt{0}{0} rectangle \punkt{8}{1};
+\foreach \x in {1,...,7}{
+	\draw \punkt{\x}{0} -- \punkt{\x}{1};
+}
+
+\fill[color=blue!20] \punkt{-1}{-3} rectangle \punkt{7}{-2};
+\fill[color=darkgreen!20] \punkt{0}{-4} rectangle \punkt{8}{-3};
+
+\node[color=darkgreen] at \punkt{-1}{-1.5} [left] 
+	{$m(X) = X^8+X^4+X^3+X+1$};
+
+\node[color=darkgreen] at \punkt{-1}{-2.7} [left]
+	{$\underbrace{X^4+X^3+X+1}_{}= X^8=\mathstrut$};
+
+\coordinate (A) at ({-4.15*\s},{-3*\s});
+\coordinate (B) at ({0*\s},{-3.5*\s});
+
+\draw[->,color=red,shorten >= 0.1cm] (A) to[out=-90,in=180] (B);
+\node[color=red] at \punkt{-3.1}{-3.8} [below] {Feedback};
+
+\node at \punkt{-0.5}{-2.5} {\texttt{1}};
+\node at \punkt{0.5}{-2.5} {\texttt{0}};
+\node at \punkt{1.5}{-2.5} {\texttt{0}};
+\node at \punkt{2.5}{-2.5} {\texttt{1}};
+\node at \punkt{3.5}{-2.5} {\texttt{0}};
+\node at \punkt{4.5}{-2.5} {\texttt{1}};
+\node at \punkt{5.5}{-2.5} {\texttt{0}};
+\node at \punkt{6.5}{-2.5} {\texttt{1}};
+\node at \punkt{7.5}{-2.5} {\texttt{0}};
+
+\node[color=darkgreen] at \punkt{0.5}{-3.5} {\texttt{0}};
+\node[color=darkgreen] at \punkt{1.5}{-3.5} {\texttt{0}};
+\node[color=darkgreen] at \punkt{2.5}{-3.5} {\texttt{0}};
+\node[color=darkgreen] at \punkt{3.5}{-3.5} {\texttt{1}};
+\node[color=darkgreen] at \punkt{4.5}{-3.5} {\texttt{1}};
+\node[color=darkgreen] at \punkt{5.5}{-3.5} {\texttt{0}};
+\node[color=darkgreen] at \punkt{6.5}{-3.5} {\texttt{1}};
+\node[color=darkgreen] at \punkt{7.5}{-3.5} {\texttt{1}};
+
+\draw \punkt{0}{-4} rectangle \punkt{8}{-2};
+\draw \punkt{0}{-3} -- \punkt{8}{-3};
+\foreach \x in {1,...,7}{
+	\draw \punkt{\x}{-4} -- \punkt{\x}{-2};
+}
+
+\foreach \x in {0.5,1.5,...,7.5}{
+	\draw[->,color=blue] \punkt{\x}{-0.1} -- \punkt{(\x-1)}{-1.9};
+}
+
+\draw \punkt{0}{-6} rectangle \punkt{8}{-5};
+\foreach \x in {1,...,7}{
+	\draw \punkt{\x}{-6} -- \punkt{\x}{-5};
+}
+
+\node at \punkt{0.5}{-5.5} {\texttt{0}};
+\node at \punkt{1.5}{-5.5} {\texttt{0}};
+\node at \punkt{2.5}{-5.5} {\texttt{1}};
+\node at \punkt{3.5}{-5.5} {\texttt{1}};
+\node at \punkt{4.5}{-5.5} {\texttt{0}};
+\node at \punkt{5.5}{-5.5} {\texttt{0}};
+\node at \punkt{6.5}{-5.5} {\texttt{0}};
+\node at \punkt{7.5}{-5.5} {\texttt{1}};
+
+\node at \punkt{4}{-4.5} {$\|$};
+
+\node at \punkt{10.3}{-3} [left]
+	{$\left.\begin{matrix}\\ \\ \\ \end{matrix}\right\} + = \text{XOR}$};
+
+\draw[<-,shorten >= 0.1cm, shorten <= 0.1cm]
+	\punkt{8.0}{-2.0} arc (-30:30:{2.0*\s});
+\node at \punkt{8.3}{-1} [right] {$\mathstrut \cdot X$};
+
+\node at \punkt{8.1}{-5.5} [right] {$=X\cdot p(X)\mathstrut$};
+
+\end{tikzpicture}
+\end{document}
+
diff --git a/buch/chapters/90-crypto/images/shift.pdf b/buch/chapters/90-crypto/images/shift.pdf
new file mode 100644
index 0000000..b007378
--- /dev/null
+++ b/buch/chapters/90-crypto/images/shift.pdf
diff --git a/buch/chapters/90-crypto/images/shift.tex b/buch/chapters/90-crypto/images/shift.tex
new file mode 100644
index 0000000..bcdf819
--- /dev/null
+++ b/buch/chapters/90-crypto/images/shift.tex
@@ -0,0 +1,131 @@
+%
+% shift.tex -- template for standalon tikz images
+%
+% (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+%
+\documentclass[tikz]{standalone}
+\usepackage{amsmath}
+\usepackage{times}
+\usepackage{txfonts}
+\usepackage{pgfplots}
+\usepackage{csvsimple}
+\usetikzlibrary{arrows,intersections,math}
+\begin{document}
+\def\skala{1}
+\begin{tikzpicture}[>=latex,thick,scale=\skala]
+
+\definecolor{darkgreen}{rgb}{0,0.6,0}
+
+\def\s{0.8}
+\def\punkt#1#2{({#1*\s},{#2*\s})}
+
+\def\feld#1#2#3#4{
+	\fill[color=#3] \punkt{#1}{#2} rectangle \punkt{(#1+1)}{(#2+1)};
+	\node at \punkt{(#1+0.5)}{(#2+0.5)} {$\mathstrut #4$};
+}
+\def\gitter{
+	\draw \punkt{0}{0} rectangle \punkt{8}{4};
+	\foreach \x in {1,...,7}{
+		\draw \punkt{\x}{0} -- \punkt{\x}{4};
+	}
+	\foreach \y in {1,...,3}{
+		\draw \punkt{0}{\y} -- \punkt{8}{\y};
+	}
+}
+
+\begin{scope}
+	\feld{0}{3}{red!20}{b_{0}}
+	\feld{0}{2}{red!20}{b_{1}}
+	\feld{0}{1}{red!20}{b_{2}}
+	\feld{0}{0}{red!20}{b_{3}}
+
+	\feld{1}{3}{red!10}{b_{4}}
+	\feld{1}{2}{red!10}{b_{5}}
+	\feld{1}{1}{red!10}{b_{6}}
+	\feld{1}{0}{red!10}{b_{7}}
+
+	\feld{2}{3}{yellow!20}{b_{8}}
+	\feld{2}{2}{yellow!20}{b_{9}}
+	\feld{2}{1}{yellow!20}{b_{10}}
+	\feld{2}{0}{yellow!20}{b_{11}}
+
+	\feld{3}{3}{yellow!10}{b_{12}}
+	\feld{3}{2}{yellow!10}{b_{13}}
+	\feld{3}{1}{yellow!10}{b_{14}}
+	\feld{3}{0}{yellow!10}{b_{15}}
+
+	\feld{4}{3}{darkgreen!20}{b_{16}}
+	\feld{4}{2}{darkgreen!20}{b_{17}}
+	\feld{4}{1}{darkgreen!20}{b_{18}}
+	\feld{4}{0}{darkgreen!20}{b_{19}}
+
+	\feld{5}{3}{darkgreen!10}{b_{20}}
+	\feld{5}{2}{darkgreen!10}{b_{21}}
+	\feld{5}{1}{darkgreen!10}{b_{22}}
+	\feld{5}{0}{darkgreen!10}{b_{23}}
+
+	\feld{6}{3}{blue!20}{b_{24}}
+	\feld{6}{2}{blue!20}{b_{25}}
+	\feld{6}{1}{blue!20}{b_{26}}
+	\feld{6}{0}{blue!20}{b_{27}}
+
+	\feld{7}{3}{blue!10}{b_{28}}
+	\feld{7}{2}{blue!10}{b_{29}}
+	\feld{7}{1}{blue!10}{b_{30}}
+	\feld{7}{0}{blue!10}{b_{31}}
+
+	\gitter
+
+	\draw[->] \punkt{8.1}{2} -- \punkt{9.3}{2};
+\end{scope}
+
+
+\begin{scope}[xshift=7.5cm]
+
+	\feld{0}{3}{red!20}{b_{0}}
+	\feld{1}{2}{red!20}{b_{1}}
+	\feld{2}{1}{red!20}{b_{2}}
+	\feld{3}{0}{red!20}{b_{3}}
+
+	\feld{1}{3}{red!10}{b_{4}}
+	\feld{2}{2}{red!10}{b_{5}}
+	\feld{3}{1}{red!10}{b_{6}}
+	\feld{4}{0}{red!10}{b_{7}}
+
+	\feld{2}{3}{yellow!20}{b_{8}}
+	\feld{3}{2}{yellow!20}{b_{9}}
+	\feld{4}{1}{yellow!20}{b_{10}}
+	\feld{5}{0}{yellow!20}{b_{11}}
+
+	\feld{3}{3}{yellow!10}{b_{12}}
+	\feld{4}{2}{yellow!10}{b_{13}}
+	\feld{5}{1}{yellow!10}{b_{14}}
+	\feld{6}{0}{yellow!10}{b_{15}}
+
+	\feld{4}{3}{darkgreen!20}{b_{16}}
+	\feld{5}{2}{darkgreen!20}{b_{17}}
+	\feld{6}{1}{darkgreen!20}{b_{18}}
+	\feld{7}{0}{darkgreen!20}{b_{19}}
+
+	\feld{5}{3}{darkgreen!10}{b_{20}}
+	\feld{6}{2}{darkgreen!10}{b_{21}}
+	\feld{7}{1}{darkgreen!10}{b_{22}}
+	\feld{0}{0}{darkgreen!10}{b_{23}}
+
+	\feld{6}{3}{blue!20}{b_{24}}
+	\feld{7}{2}{blue!20}{b_{25}}
+	\feld{0}{1}{blue!20}{b_{26}}
+	\feld{1}{0}{blue!20}{b_{27}}
+
+	\feld{7}{3}{blue!10}{b_{28}}
+	\feld{0}{2}{blue!10}{b_{29}}
+	\feld{1}{1}{blue!10}{b_{30}}
+	\feld{2}{0}{blue!10}{b_{31}}
+
+	\gitter
+
+\end{scope}
+
+\end{tikzpicture}
+\end{document}
+