\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{SinaVafadar}
\pdfinfo{
  /Title (decode-tcp-and-udp.pdf)
  /Creator (Cheatography)
  /Author (SinaVafadar)
  /Subject (Decode TCP and UDP Cheat Sheet)
}

% Lengths and widths
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\addtolength{\textheight}{-1cm}
\addtolength{\hoffset}{-3cm}
\addtolength{\voffset}{-2cm}
\setlength{\tabcolsep}{0.2cm} % Space between columns
\setlength{\headsep}{-12pt} % Reduce space between header and content
\setlength{\headheight}{85pt} % If less, LaTeX automatically increases it
\renewcommand{\footrulewidth}{0pt} % Remove footer line
\renewcommand{\headrulewidth}{0pt} % Remove header line
\renewcommand{\seqinsert}{\ifmmode\allowbreak\else\-\fi} % Hyphens in seqsplit
% This two commands together give roughly
% the right line height in the tables
\renewcommand{\arraystretch}{1.3}
\onehalfspacing

% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
\newcolumntype{x}[1]{>{\raggedright}p{#1}} % New column types for ragged-right paragraph columns
\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
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\definecolor{FootBackground}{HTML}{666666}
\definecolor{TextColor}{HTML}{333333}
\definecolor{DarkBackground}{HTML}{6BE3A0}
\definecolor{LightBackground}{HTML}{ECFBF3}
\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Decode TCP and UDP Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{SinaVafadar} via \textcolor{DarkBackground}{\uline{cheatography.com/128837/cs/25317/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}SinaVafadar \\
  \uline{cheatography.com/sinavafadar} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 20th November, 2020.\\
   Updated 20th November, 2020.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{x{4.16 cm} x{3.84 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Transport Layer}}  \tn
% Row 0
\SetRowColor{LightBackground}
Number of Layer & 4th Layer of OSI Model \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Role & Transport Data \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
Protocols & UDP - TCP \tn 
% Row Count 4 (+ 1)
% Row 3
\SetRowColor{white}
PDU (Protocol Data Unit) & Segment \tn 
% Row Count 6 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Address & Port Number \tn 
% Row Count 7 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{3.12 cm} x{4.88 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{UDP Features}}  \tn
% Row 0
\SetRowColor{LightBackground}
Type of Connection & Connectionless (Does Not Need Connection Setup) \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Application & Time-Sensitive Connections \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Number of Fields in Header & Four Field Header \tn 
% Row Count 6 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{3.12 cm} x{4.88 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{TCP Features}}  \tn
% Row 0
\SetRowColor{LightBackground}
Type of Connection & Connection-Oriented (Needs Connection Setup) \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Application & Reliable Connections \tn 
% Row Count 3 (+ 1)
% Row 2
\SetRowColor{LightBackground}
Number of Fields in Header & Eleven Field Header \tn 
% Row Count 5 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{4.4 cm} x{3.6 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Commands}}  \tn
% Row 0
\SetRowColor{LightBackground}
Active UDP Connections & `netstat -anp udp` \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
Active TCP Connections & `netstat -anp tcp` \tn 
% Row Count 2 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{2.96 cm} x{5.04 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{UDP Header Fields}}  \tn
% Row 0
\SetRowColor{LightBackground}
Source Port 16-bit & Port on The Receiver's Side \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Destination Port 16-bit & Port on The Sender's Side \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Length 16-bit & The Number of Bytes in The UDP Header And Any Data Follows \tn 
% Row Count 7 (+ 3)
% Row 3
\SetRowColor{white}
Checksum 16-bit & Calculated Value for Ensuring Data Integrity \tn 
% Row Count 9 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{2.96 cm} x{5.04 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{TCP Ports}}  \tn
% Row 0
\SetRowColor{LightBackground}
Source Port 16-bit & The Port on The Sender Side \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Destination Port 16-bit & The Port on The Receiver Side \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Stream & A Communication Between Two Endpoints \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
TCP Segment Length & The Value of The TCP Payload (The Data That Follows The TCP Header) \tn 
% Row Count 9 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{3.28 cm} x{4.72 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Sequencing and Acknowledging in TCP}}  \tn
% Row 0
\SetRowColor{LightBackground}
Sequence Number 32-bit & The Byte Number of The First Byte of Data \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Next Sequence Number & Current Sequence Number Plus The TCP Segment Length \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
Acknowledgment Number 32-bit & The Sequence Number of The Next Byte The Receiver Expects to Receive \tn 
% Row Count 8 (+ 3)
% Row 3
\SetRowColor{white}
Offset & Indicates The Length of The TCP Header \tn 
% Row Count 10 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{1.14 cm} p{0.76 cm} x{5.7 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{3}{x{8.4cm}}{\bf\textcolor{white}{Flags in TCP}}  \tn
% Row 0
\SetRowColor{LightBackground}
\seqsplit{Reserved} & 3-bit & For Future Use \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Nonce & 1-bit & Experimental Use \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
CWR & 1-bit & Respond to Indications of Network Congestion with Congestion Avoidance \tn 
% Row Count 7 (+ 3)
% Row 3
\SetRowColor{white}
ECE & 1-bit & Notify The Endpoints of Any Network Congestion to Avoid Dropping Packets \tn 
% Row Count 10 (+ 3)
% Row 4
\SetRowColor{LightBackground}
URG & 1-bit & Indicates a Packet That Should Have Priority \tn 
% Row Count 12 (+ 2)
% Row 5
\SetRowColor{white}
ACK & 1-bit & Acknowledging The Data Was Received \tn 
% Row Count 14 (+ 2)
% Row 6
\SetRowColor{LightBackground}
PSH & 1-bit & Informing Data Should Be Sent Immediately \tn 
% Row Count 16 (+ 2)
% Row 7
\SetRowColor{white}
RST & 1-bit & Aborting The TCP Connection \tn 
% Row Count 18 (+ 2)
% Row 8
\SetRowColor{LightBackground}
SYN & 1-bit & Synchronizing The Sequence Numbers \tn 
% Row Count 20 (+ 2)
% Row 9
\SetRowColor{white}
FIN & 1-bit & closing The Connection \tn 
% Row Count 22 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}---}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{3.12 cm} x{4.88 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Dissecting Window Size}}  \tn
% Row 0
\SetRowColor{LightBackground}
Window Size 16-bit & Controls The Flow of Data \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Scaling Factor & A Value For Expanding Window Size \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Window Size Scaling Factor & 2 \textasciicircum{} (Scaling Factor) if Scaling Factor \textgreater{}= 0 \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
Calculated Window Size & Window Size * Window Size Scaling Factor \tn 
% Row Count 8 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{2.08 cm} x{5.92 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Additional Header Values in TCP}}  \tn
% Row 0
\SetRowColor{LightBackground}
Checksum & A Calculated Value For Error Detection \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Urgent Pointer & Points to The Sequence Number of Urgent Data \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Options & Extra Options Like Timestamps And No-operation \tn 
% Row Count 6 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}