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+\documentclass[a4paper,12pt]{scrartcl}
+\usepackage[ngerman]{babel}
+\usepackage{graphicx} %BIlder einbinden
+\usepackage{amsmath} %erweiterte Mathe-Zeichen
+\usepackage{amsfonts} %weitere fonts
+\usepackage[utf8]{inputenc} %Umlaute & Co
+\usepackage{hyperref} %Links
+\usepackage{ifthen} %ifthenelse
+\usepackage{enumerate}
+\usepackage{stmaryrd}
+
+\usepackage{color}
+\usepackage{algpseudocode} %Pseudocode
+\usepackage{dsfont} % schöne Zahlenräumezeichen
+\usepackage{amssymb, amsthm} %noch stärker erweiterte Mathe-Zeichen
+\usepackage{tikz} %TikZ ist kein Zeichenprogramm
+\usetikzlibrary{trees,automata,arrows,shapes}
+\usepackage{pgfplots}
+
+\pagestyle{empty}
+
+
+\topmargin-50pt
+
+
+\newcounter{aufgabe}
+\def\tand{&}
+
+\newcommand{\makeTableLine}[2][0]{%
+  \setcounter{aufgabe}{1}%
+  \whiledo{\value{aufgabe} < #1}%
+  {%
+    #2\tand\stepcounter{aufgabe}%
+  }
+}
+
+\newcommand{\aufgTable}[1]{
+  \def\spalten{\numexpr #1 + 1 \relax}
+  \begin{tabular}{|*{\spalten}{p{1cm}|}}
+    \makeTableLine[\spalten]{E\theaufgabe}$\Sigma$~~\\ \hline
+    \rule{0pt}{15pt}\makeTableLine[\spalten]{}\\
+  \end{tabular}
+}
+
+\def\header#1#2#3#4#5#6#7{\pagestyle{empty}
+\begin{minipage}[t]{0.47\textwidth}
+\begin{flushleft}
+{\bf #4}\\
+#5
+\end{flushleft}
+\end{minipage}
+\begin{minipage}[t]{0.5\textwidth}
+\begin{flushright}
+#6 \vspace{0.5cm}\\
+%                 Number of Columns    Definition of Columns      second empty line
+% \begin{tabular}{|*{5}{C{1cm}|}}\hline A1&A2&A3&A4&$\Sigma$\\\hline&&&&\\\hline\end{tabular}\\\vspace*{0.1cm}
+\aufgTable{#7}
+\end{flushright}
+\end{minipage}
+\vspace{1cm}
+\begin{center}
+{\Large\bf Sheet #1}
+
+{(Hand in #3)}
+\end{center}
+}
+
+
+
+%counts the exercisenumber
+\newcounter{n}
+
+%Kommando für Aufgaben
+%\Aufgabe{AufgTitel}{Punktezahl}
+\newcommand{\Aufgabe}[2]{\stepcounter{n}
+    \textbf{Exercise \arabic{n}: #1} (#2 Points)}
+
+\newcommand{\textcorr}[1]{\textcolor{red}{#1}}
+\newenvironment{corr}{\color{red}}{\color{black}\newline}
+\newcommand{\ok}{\begin{corr}
+            $\checkmark$
+        \end{corr}}
+
+\newcommand{\enot}[2]{#1 \cdot 10^{#2}}
+
+\begin{document}
+%\header{BlattNr}{Tutor}{Abgabedatum}{Vorlesungsname}{Namen}{Semester}{Anzahl Aufgaben}
+\header{9}{}{2015-12-16}{Kommunikationsnetze}{\textit{Jonas Jaszkowic, 3592719}\\\textit{Jan-Peter Hohloch, 3908712}}{WS 15/16}{4}
+\vspace{1cm}
+\Aufgabe{Bridges, Ports and Spanning Trees}{5+5+5+5+10+10+10+10}
+\begin{enumerate}
+	\item bla 
+	\item bla
+	\item bla
+	\item bla
+	\item bla
+	\item bla
+	\item bla
+	\item bla
+
+\end{enumerate}
+\Aufgabe{Optical Networks - SONET}{5+10+5+5}
+\begin{enumerate}
+	\item See to \url{http://goo.gl/QyNMLg}. A STS multiplexer is the start and end point of an SONET network and combines multiple STS-signals into an STS-n signal. An add/drop multiplexer however, adds or drops single STS-1 signals from a multiplexed STS-n signal.
+	\item 
+	\begin{enumerate}
+		\item \textbf{Photonic layer}: physical specification of optical fiber channel. Encoding with unipolar NRZ, 1 is presence of light, 0 is absence of light.
+		\item \textbf{Section layer}: handles framing, scrambling and error control.
+		\item \textbf{Line layer}: provides access to STS-1 signals for adding or dropping individual multiplexed signals on a line.
+		\item \textbf{Path layer}: combines n STS-1 signals to an STS-n signal. Combines lower bit rate signals into synchronous payload envelopes.
+	\end{enumerate}
+	\item A SONET regenerator is something like a repeater for optical signals. Whereas a repeater is level one, a regenerator acts on level two because it is also responsible for framing, scrambling and error control. The frame is regenerated, management information is added. A repeater would only recover every single bit.
+	\item SONET is called a synchronous network because it uses STS (\textbf{synchronous} transport signal) multiplexing and demultiplexing.
+\end{enumerate}
+\end{document}