diff --git a/20231109/Zeichen_123.pdf b/20231109/Zeichen_123.pdf
new file mode 120000
index 0000000000000000000000000000000000000000..fdbc897227df059cfda790a16555e6e417682116
--- /dev/null
+++ b/20231109/Zeichen_123.pdf
@@ -0,0 +1 @@
+../common/Zeichen_123.pdf
\ No newline at end of file
diff --git a/20231109/dbs-20231109.pdf b/20231109/dbs-20231109.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..85f5b91ab900ac5002298cfcf4895b38bc286cb0
Binary files /dev/null and b/20231109/dbs-20231109.pdf differ
diff --git a/20231109/dbs-20231109.tex b/20231109/dbs-20231109.tex
new file mode 100644
index 0000000000000000000000000000000000000000..347f40396df508c6ed80563c4fb9229db960e651
--- /dev/null
+++ b/20231109/dbs-20231109.tex
@@ -0,0 +1,341 @@
+% dbs-20221109.pdf - Lecture Slides on Databases and Information Security
+% Copyright (C) 2023  Peter Gerwinski
+%
+% This document is free software: you can redistribute it and/or
+% modify it either under the terms of the Creative Commons
+% Attribution-ShareAlike 3.0 License, or under the terms of the
+% GNU General Public License as published by the Free Software
+% Foundation, either version 3 of the License, or (at your option)
+% any later version.
+%
+% This document is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with this document.  If not, see <http://www.gnu.org/licenses/>.
+%
+% You should have received a copy of the Creative Commons
+% Attribution-ShareAlike 3.0 Unported License along with this
+% document.  If not, see <http://creativecommons.org/licenses/>.
+
+% README: Kurzeinführung TCP/IP
+
+\documentclass[10pt,t]{beamer}
+
+\usepackage{pgslides}
+\usepackage{tikz}
+\usepackage{rotating}
+
+\newcommand{\vfilll}{\vspace{0pt plus 1filll}}
+
+\newcommand{\underconstruction}{%
+  \begin{picture}(0,0)
+    \put(11,1.2){\makebox(0,0)[b]{\includegraphics[width=1.5cm]{Zeichen_123.pdf}}}
+    \put(11,0.9){\makebox(0,0)[t]{\shortstack{Änderungen\\vorbehalten}}}
+  \end{picture}}
+
+\title{Datenbanken und Datensicherheit}
+\author{Prof.\ Dr.\ rer.\ nat.\ Peter Gerwinski}
+\date{9.\ November 2023}
+
+\definecolor{ethernet}{rgb}{0.95,0.95,0.95}
+\definecolor{ip}{rgb}{0.85,0.85,1.0}
+\definecolor{tcp}{rgb}{0.925,1.0,0.925}
+\definecolor{data}{rgb}{1.0,0.85,0.85}
+
+\newcommand{\bitno}[1]{%
+  \begin{picture}(1,1)
+    \scriptsize
+    \put(0,0){\line(1,0){1}}
+    \put(0,0){\line(0,1){1}}
+    \put(0,1){\line(1,0){1}}
+    \put(1,0){\line(0,1){1}}
+    \put(0.5,0.5){\makebox(0,0){#1}}
+  \end{picture}}
+\newcommand{\byteno}[1]{%
+  \begin{picture}(2,1)
+    \scriptsize
+    \put(0,0){\line(1,0){2}}
+    \put(0,0){\line(0,1){1}}
+    \put(0,1){\line(1,0){2}}
+    \put(2,0){\line(0,1){1}}
+    \put(1,0.5){\makebox(0,0){#1}}
+  \end{picture}}
+\newcommand{\vbitno}[1]{%
+  \begin{picture}(2,3)
+    \scriptsize
+    \put(0,0){\line(1,0){2}}
+    \put(0,0){\line(0,1){3}}
+    \put(0,3){\line(1,0){2}}
+%    \put(2,0){\line(0,1){3}}
+    \put(1.6,1.5){\makebox(0,0)[r]{#1}}
+  \end{picture}}
+\newcommand{\vqbitno}[1]{%
+  \begin{picture}(2,11.875) % ???
+    \scriptsize
+    \put(0,0){\line(1,0){2}}
+    \put(0,0){\line(0,1){12}}
+    \put(0,12){\line(1,0){2}}
+%    \put(2,0){\line(0,1){12}}
+    \put(1.6,10.5){\makebox(0,0)[r]{#1}}
+  \end{picture}}
+\newcommand{\genericbitbox}[5]{%
+  \begin{picture}(#1,3)
+    \footnotesize
+    \def\testl{#3}
+    \def\testr{#4}
+    \ifx\testl\testr
+      \put(0,0){\color{#3}\rule{#1\unitlength}{3\unitlength}}
+    \else
+      \put(0,0.0){\color{#3}\rule{#1\unitlength}{0.5\unitlength}}
+      \put(0,0.5){\color{#4}\rule{#1\unitlength}{2\unitlength}}
+      \put(0,2.5){\color{#3}\rule{#1\unitlength}{0.5\unitlength}}
+      \put(0,0){\color{#3}\rule{0.5\unitlength}{3\unitlength}}
+      \put(#1,0){\color{#3}\makebox(0,0)[br]{\rule{0.5\unitlength}{3\unitlength}}}
+    \fi
+    \put(0,0){\line(1,0){#1}}
+    \put(0,3){\line(1,0){#1}}
+    \def\testl{flex}
+    \def\testr{#5}
+    \ifx\testl\testr
+      \put(0,0){\line(0,1){1.2}}
+      \put(#1,0){\line(0,1){1.2}}
+      \put(0,3){\line(0,-1){1.2}}
+      \put(#1,3){\line(0,-1){1.2}}
+      \put(0,1.0){\makebox(0,0){\large\char126}}
+      \put(0,1.6){\makebox(0,0){\large\char126}}
+      \put(#1,1.0){\makebox(0,0){\large\char126}}
+      \put(#1,1.6){\makebox(0,0){\large\char126}}
+    \else
+      \put(0,0){\line(0,1){3}}
+      \put(#1,0){\line(0,1){3}}
+    \fi
+    \put(0,1.5){\makebox(0,0)[l]{\hbox to #1\unitlength{\hss#2\hss}}}
+  \end{picture}}
+\newcommand{\bitbox}[2]{\genericbitbox{#1}{#2}{\headercolor}{\headercolor}{normal}}
+\newcommand{\flexbitbox}[2]{\genericbitbox{#1}{#2}{\headercolor}{\headercolor}{flex}}
+\newcommand{\databitbox}[2]{\genericbitbox{#1}{#2}{\headercolor}{\datacolor}{flex}}
+\newcommand{\qbitbox}[2]{%
+  \begin{picture}(#1,11.875) % ???
+    \footnotesize
+    \put(0,0){\color{\headercolor}\rule{#1\unitlength}{12\unitlength}}
+    \put(0,0){\line(1,0){#1}}
+    \put(0,12){\line(1,0){#1}}
+    \put(0,0){\line(0,1){12}}
+    \put(#1,0){\line(0,1){12}}
+    \put(0,6){\makebox(0,0)[l]{\hbox to #1\unitlength{\hss#2\hss}}}
+  \end{picture}}
+\newcommand{\emptybox}[3]{%
+  \begin{picture}(#1,#2)
+    \put(0,#2){\makebox(0,0)[tl]{\footnotesize #3}}
+  \end{picture}}
+\newcommand{\headerbox}[1]{\emptybox{2}{1}{#1}}
+
+\begin{document}
+
+\maketitleframe
+
+\nosectionnonumber{\inserttitle}
+
+\begin{frame}
+
+  \shownosectionnonumber
+
+  \begin{itemize}
+    \item[\textbf{1}] \textbf{Einführung}
+      \hfill\makebox(0,0)[br]{\raisebox{2.25ex}{\url{https://gitlab.cvh-server.de/pgerwinski/dbs}}}%
+    \item[\textbf{2}] \textbf{Kurzeinführung Unix}
+    \item[\textbf{3}] \textbf{Kurzeinführung TCP/IP}
+      \begin{itemize}
+        \item[3.1] IP-Adressen
+        \item[3.2] MAC-Adressen
+        \item[3.3] TCP- und UDP-Ports
+        \color{medgreen}
+        \item[3.4] TCP-Protokolle
+        \item[3.5] Routing
+        \item[3.6] Netzwerkanalyse
+        \item[3.7] SSH
+        \color{red}
+        \item[3.8] X11
+      \end{itemize}
+    \item[\textbf{4}] \textbf{Relationale Datenbanken}
+    \vspace*{-\smallskipamount}
+    \item[\textbf{\dots}]
+  \end{itemize}
+
+  \vfilll
+  \underconstruction
+
+\end{frame}
+
+\setcounter{section}{2}
+\section{Kurzeinführung TCP/IP}
+\setcounter{subsection}{3}
+\subsection{TCP-Protokolle}
+
+\begin{frame}
+
+  \showsubsection
+
+  \begin{itemize}
+    \item
+      \textbf{SMTP}\\
+      \lstinline[style=cmd]{HELO cassini}\\
+      \lstinline[style=cmd]{MAIL FROM: <example@example.com>}\\
+      \lstinline[style=cmd]{RCPT TO: <beispiel@example.de>}\\
+      \lstinline[style=cmd]{DATA}\\
+      (E-Mail-Header -- Teil der Nutzdaten)\\
+      \lstinline[style=cmd]{From: Eddie Example <example@example.com>}\\
+      \lstinline[style=cmd]{To: Bert Beispiel <beispiel@example.de>}\\
+      \lstinline[style=cmd]{Subject: Hello, world!}\\
+      (Leerzeile)\\
+      \lstinline[style=cmd]{Hi, there!}\\
+      \lstinline[style=cmd]{.}
+%    \pause
+    \smallskip
+    \item
+      \textbf{HTTP}\\
+      \lstinline[style=cmd]{GET / HTTP/1.1}\\
+      \lstinline[style=cmd]{Host: www.hs-bochum.de}\\
+      (Leerzeile)
+%    \begin{onlyenv}<2>
+      \par\medskip
+%      URL: Schema://Benutzer:Passwort@Rechner:port/Pfad?Query\#Fragment
+%    \end{onlyenv}
+%    \pause
+    \medskip
+    \item
+      Protokolle "`mal eben"' selbst schreiben:
+      \lstinline[style=cmd]{nc -c} oder \file{inetd}
+  \end{itemize}
+
+\end{frame}
+
+\subsection{Routing}
+
+\begin{frame}[fragile]
+
+  \showsubsection
+
+  \begin{itemize}
+    \item
+      \lstinline[style=cmd]{ip route} (Linux)\\
+      \lstinline[style=cmd]{route} (MS-Windows, Unix)\\
+      \lstinline[style=cmd]{netstat -nr} (MacOS)
+%                                                \\[\medskipamount]
+%      \includegraphics[width=11cm]{../20171026/photo-20171026-162455.jpg}
+  \end{itemize}
+
+  \medskip
+
+  \begin{lstlisting}[style=terminal]
+    # route -n
+    Kernel-IP-Routentabelle
+    Ziel          Router        Genmask        [...]  Iface
+    0.0.0.0       192.168.42.1  0.0.0.0        [...]  wlan0
+    169.254.0.0   0.0.0.0       255.255.0.0    [...]  wlan0
+    192.168.42.0  0.0.0.0       255.255.255.0  [...]  wlan0
+  \end{lstlisting}
+
+  \bigskip
+
+  Netzmaske:\\
+  Wenn nach Und-Verknüpfung mit IP-Adresse gleich,
+  \textarrow\ im gleichen Netz
+
+  \medskip
+
+  \lstinline[style=terminal]{255.255.240.0} ist dasselbe wie
+  \lstinline[style=terminal]{/20}\\
+  (20 Bit sind 1; die restlichen 12 Bit sind 0)
+
+\end{frame}
+
+\subsection{Netzwerkanalyse}
+
+\begin{frame}
+
+  \showsubsection
+
+  \begin{itemize}
+    \item
+      \lstinline[style=cmd]{tcpdump}
+    \item
+      \lstinline[style=cmd]{wireshark}
+    \item
+      \lstinline[style=cmd]{ettercap}
+  \end{itemize}
+
+\end{frame}
+
+\subsection{SSH}
+
+\begin{frame}
+
+  \showsubsection
+
+  \begin{itemize}
+    \item
+      \lstinline[style=cmd]{SSH <Rechner>}
+    \item
+      \lstinline[style=cmd]{-C}: Komprimierung
+    \item
+      \lstinline[style=cmd]{-L}: lokalen Port auf Remote-Port umleiten
+    \item
+      \lstinline[style=cmd]{-R}: Remote-Port auf lokalen Port umleiten
+  \end{itemize}
+
+\end{frame}
+
+\subsection{X11}
+
+\begin{frame}
+
+  \showsubsection
+
+  \begin{itemize}
+    \item
+      Grafik-Bildschirm und Eingabegeräte über's Netz
+    \item
+      \lstinline[style=cmd]{DISPLAY}-Variable: X-Server: Rechner und Bildschirm
+    \item
+      \lstinline[style=cmd]{ssh -X}: X11-Forwarding
+  \end{itemize}
+
+\end{frame}
+
+\nosectionnonumber{\inserttitle}
+
+\begin{frame}
+
+  \shownosectionnonumber
+
+  \begin{itemize}
+    \item[\textbf{1}] \textbf{Einführung}
+      \hfill\makebox(0,0)[br]{\raisebox{2.25ex}{\url{https://gitlab.cvh-server.de/pgerwinski/dbs}}}%
+    \item[\textbf{2}] \textbf{Kurzeinführung Unix}
+    \item[\textbf{3}] \textbf{Kurzeinführung TCP/IP}
+      \begin{itemize}
+        \item[3.1] IP-Adressen
+        \item[3.2] MAC-Adressen
+        \item[3.3] TCP- und UDP-Ports
+        \color{medgreen}
+        \item[3.4] TCP-Protokolle
+        \item[3.5] Routing
+        \item[3.6] Netzwerkanalyse
+        \item[3.7] SSH
+        \item[3.8] X11
+      \end{itemize}
+    \item[\textbf{4}] \textbf{Relationale Datenbanken}
+    \vspace*{-\smallskipamount}
+    \item[\textbf{\dots}]
+  \end{itemize}
+
+  \vfilll
+  \underconstruction
+
+\end{frame}
+
+\end{document}
diff --git a/20231109/logo-hochschule-bochum-cvh-text-v2.pdf b/20231109/logo-hochschule-bochum-cvh-text-v2.pdf
new file mode 120000
index 0000000000000000000000000000000000000000..4aa99b8f81061aca6dcaf43eed2d9efef40555f8
--- /dev/null
+++ b/20231109/logo-hochschule-bochum-cvh-text-v2.pdf
@@ -0,0 +1 @@
+../common/logo-hochschule-bochum-cvh-text-v2.pdf
\ No newline at end of file
diff --git a/20231109/logo-hochschule-bochum.pdf b/20231109/logo-hochschule-bochum.pdf
new file mode 120000
index 0000000000000000000000000000000000000000..b6b9491e370e499c9276918182cdb82cb311bcd1
--- /dev/null
+++ b/20231109/logo-hochschule-bochum.pdf
@@ -0,0 +1 @@
+../common/logo-hochschule-bochum.pdf
\ No newline at end of file
diff --git a/20231109/pgslides.sty b/20231109/pgslides.sty
new file mode 120000
index 0000000000000000000000000000000000000000..5be1416f4216f076aa268901f52a15d775e43f64
--- /dev/null
+++ b/20231109/pgslides.sty
@@ -0,0 +1 @@
+../common/pgslides.sty
\ No newline at end of file