\documentclass[10pt,a4paper]{article}

% Packages
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\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{phamine}
\pdfinfo{
  /Title (wireless-networks.pdf)
  /Creator (Cheatography)
  /Author (phamine)
  /Subject (Wireless Networks Cheat Sheet)
}

% Lengths and widths
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% This two commands together give roughly
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% 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
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% 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{Wireless Networks Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{phamine} via \textcolor{DarkBackground}{\uline{cheatography.com/20752/cs/3632/}}}
\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}phamine \\
  \uline{cheatography.com/phamine} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 13th May, 2016.\\
   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*}{4}

\begin{tabularx}{3.833cm}{x{0.92691 cm} x{2.50609 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Physical Layer}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{radios, coaxial cable, optical fibers} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{3.833cm}}{bits "on the wire"} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
spread spectrum & reduces narrowband interference by spreading a signal's frequency to create a wider bandwidth \tn 
% Row Count 6 (+ 4)
% Row 3
\SetRowColor{white}
DSSS & direct sequence spread spectrum \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
FHSS & frequency hopping spread spectrum \tn 
% Row Count 10 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{DSSS and FHSS require time synchronization between sender and receiver.}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Maximum (Data) Bandwidth}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Shannon Channel Capacity} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}data rate = Wlog`2`(1 + S/N)} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{(theoretical) maximum number of bits that can be transmitted per second by a physical channel} \tn 
% Row Count 4 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{data rate = {\bf{bps}} \newline W = frequency range = bandwidth = {\bf{Hz}} \newline S/N = signal noise ratio = {\bf{no unit}}}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.78959 cm} x{2.64341 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Variables}}  \tn
% Row 0
\SetRowColor{LightBackground}
Signal & sending signal \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
Noise & thermal noise, background radiation (aka AWGN - additive white gaussian noise) \tn 
% Row Count 4 (+ 3)
% Row 2
\SetRowColor{LightBackground}
\seqsplit{Interference} & signals from other transmitting sources \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
SINR or SNR & S/(N + I) \tn 
% Row Count 8 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Path Loss Formulas}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{free space model} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}-{}-} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{two-ray ground reflection model} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}-{}-} \tn 
% Row Count 4 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Effects on Signal Propagation}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{path loss, shadowing, reflection, refraction, scattering, diffraction, fading% Row Count 2 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Multiplexing}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{space, time, frequency, code \newline % Row Count 1 (+ 1)
TODO: pros/cons of each% Row Count 2 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Modulation}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{AM, FM, PM \newline % Row Count 1 (+ 1)
amplitude modulation, frequency modulation, phase modulation \newline % Row Count 3 (+ 2)
TODO: \newline % Row Count 4 (+ 1)
pros/cons of each% Row Count 5 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{x{1.27021 cm} x{2.16279 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Link Layer}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{WiFi, Ethernet} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{3.833cm}}{data transfer btwn neighboring network elements} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{IEEE 802.11 DCF CSMA/CA} \tn 
% Row Count 3 (+ 1)
% Row 3
\SetRowColor{white}
CSMA/CA & carrier sensing medium access / collision avoidance \tn 
% Row Count 6 (+ 3)
% Row 4
\SetRowColor{LightBackground}
DCF & distributed coordination function - appropriate for multi-hop ad hoc networks \tn 
% Row Count 10 (+ 4)
% Row 5
\SetRowColor{white}
RTS/CTS & request to send, clear to send \tn 
% Row Count 12 (+ 2)
% Row 6
\SetRowColor{LightBackground}
hidden terminal problem & A and C want to send to B but A and C cannot see each other. both send to B and msg collides. solved by RTS/CTS \tn 
% Row Count 17 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Security}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{TODO WEP insecure as heck}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{x{1.0299 cm} x{2.4031 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Network Layer}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{IP, routing protocols} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{3.833cm}}{routing of datagrams from src to dest} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{knows addresses, routes from src to dest, elems = hosts and routers} \tn 
% Row Count 4 (+ 2)
% Row 3
\SetRowColor{white}
LS & link state \tn 
% Row Count 5 (+ 1)
% Row 4
\SetRowColor{LightBackground}
DV & distance vector \tn 
% Row Count 6 (+ 1)
% Row 5
\SetRowColor{white}
types of networks & MANET (mobile ad hoc network), mesh network, sensor network, DTN (delay tolerant network) \tn 
% Row Count 10 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Mobile IP}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{{\bf{TO}} mobile system} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}CN -\textgreater{} HA -\textgreater{} FA -\textgreater{} MN} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{{\bf{FROM}} mobile node} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}MN -\textgreater{} FA -\textgreater{} CN} \tn 
% Row Count 4 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{CN = correspondent node (aka FN = fixed node??) \newline HA = home agent \newline FA = foreign agent \newline MN = mobile node}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.71091 cm} p{0.28963 cm} p{0.34229 cm} x{1.29017 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{4}{x{3.833cm}}{\bf\textcolor{white}{DTN}}  \tn
% Row 0
\SetRowColor{LightBackground}
ALGORITHM & WHO & WHEN & TO WHOM \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
flood & all nodes & new \seqsplit{contact} & all new \tn 
% Row Count 4 (+ 3)
% Row 2
\SetRowColor{LightBackground}
direct & src only & dest & dest \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
simple \seqsplit{replication} (r) & src only & new \seqsplit{contact} & r first contacts \tn 
% Row Count 9 (+ 3)
% Row 4
\SetRowColor{LightBackground}
history (r) & all nodes & new \seqsplit{contact} & r highest ranked \tn 
% Row Count 12 (+ 3)
% Row 5
\SetRowColor{white}
erasure coding (ec-r) & src only & new \seqsplit{contact} & kr (k \textgreater{}= 1) first contacts (k is related to coding algorithm) \tn 
% Row Count 16 (+ 4)
\hhline{>{\arrayrulecolor{DarkBackground}}----}
\SetRowColor{LightBackground}
\mymulticolumn{4}{x{3.833cm}}{TODO: review history and erasure coding}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}----}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.37763 cm} x{3.05537 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Sensor Network}}  \tn
% Row 0
\SetRowColor{LightBackground}
GPSR & greedy perimeter stateless routing \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
BVR & beacon vector routing \tn 
% Row Count 2 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{TODO: study implementation and write in chart in word or something}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.3433 cm} x{3.0897 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Mesh Networks}}  \tn
% Row 0
\SetRowColor{LightBackground}
ETX & expected transmission count \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
 & = 1/(d`f` * d`r`) ... where d`f` = fwd delivery rate, d`r` = rev delivery rate \tn 
% Row Count 4 (+ 3)
% Row 2
\SetRowColor{LightBackground}
ETT & estimated transmission time TODO: this is some combo of SETT and something right??? \tn 
% Row Count 7 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.3433 cm} x{3.0897 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{MANET}}  \tn
% Row 0
\SetRowColor{LightBackground}
DSR & destination source routing \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
AODV & ad hoc on-demand distance vector \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
DSDV & destination-sequenced distance vector \tn 
% Row Count 4 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{DSR can be used for wireless mesh networks}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{x{0.96124 cm} x{2.47176 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{Transport Layer}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{TCP, UDP} \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{3.833cm}}{host-host data transfer} \tn 
% Row Count 2 (+ 1)
% Row 2
\SetRowColor{LightBackground}
UDP & user datagram protocol \tn 
% Row Count 3 (+ 1)
% Row 3
\SetRowColor{white}
TCP (wired) & transmission control protocol \tn 
% Row Count 5 (+ 2)
% Row 4
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{Mobile TCP} \tn 
% Row Count 6 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.3433 cm} p{0.3433 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{TCP - not pipelined}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{3.833cm}}{Stop and wait} \tn 
% Row Count 1 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{p{0.85825 cm} x{2.57475 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{3.833cm}}{\bf\textcolor{white}{TCP - pipelined}}  \tn
% Row 0
\SetRowColor{LightBackground}
GBN & go-back-N \tn 
% Row Count 1 (+ 1)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{3.833cm}}{selective repeat} \tn 
% Row Count 2 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Questions}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Why can't we just use NACK?} \tn 
% Row Count 1 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{3.833cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{3.833cm}}{\bf\textcolor{white}{Formulas}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Transmission} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}T = L/R} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{1}{x{3.833cm}}{Utilization - fraction of time sender is busy sending} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}U = (L/R) / (RTT + L/R)} \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{Speed of light (to convert distance to propagation delay)} \tn 
\mymulticolumn{1}{x{3.833cm}}{\hspace*{6 px}\rule{2px}{6px}\hspace*{6 px}3E8 m/s} \tn 
% Row Count 8 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{3.833cm}}{{\bf{Don't forget to use proper units (convert)}} \newline T = transmission time in {\bf{seconds}} \newline L = pack length in {\bf{bits}} \newline R = transmission rate in {\bf{bps}} \newline U = utilization {\bf{no unit}} \newline RTT = round trip time {\bf{seconds}} = propagation delay * 2}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}