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+\documentclass[14pt,aspectratio=169]{beamer}
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+
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+\usetheme{Minimalist}
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+\usepackage{tikz}
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+\usetikzlibrary{calc,shapes}
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+\usepackage{ulem}
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+
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+
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+
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+\title{Network Security}
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+\subtitle{with Netsim}
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+\author{Vecna\thanks{building on work by Erinn Atwater, Cecylia Bocovich, Miti Mazmudar, Sajin Sasy, Parjanya Vyas, and Bailey Kacsmar}\thanks{with visuals from Simon Oya and Ian Goldberg}}
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+\institute{University of Waterloo}
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+\date{2024 May 13}
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+
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+\newcommand\srccolor{blue}
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+\newcommand\dstcolor{purple}
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+\newcommand\protocolor{cyan}
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+\newcommand\msgcolor{orange}
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+
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+
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+\pgfdeclareimage[width=1cm]{router}{router}
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+\pgfdeclareimage[width=1cm]{basestation}{basestation}
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+\pgfdeclareimage[width=1cm]{mobile}{mobile}
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+\pgfdeclareimage[width=1cm]{server}{server}
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+\pgfdeclareimage[width=1cm]{desktop}{desktop}
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+\pgfdeclareimage[width=1cm]{scroll}{scroll}
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+\pgfdeclareimage[width=1cm]{evilscroll}{evilscroll}
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+\pgfdeclareimage[width=8cm]{postcard}{postcard}
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+\pgfdeclareimage[width=8cm]{envelope}{envelope}
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+\pgfdeclareimage[width=2cm]{cat}{cat-instructor}
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+\pgfdeclareimage[width=1cm]{alice}{alice}
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+\pgfdeclareimage[width=1cm]{bob}{bob}
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+\pgfdeclareimage[width=1cm]{carol}{carol}
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+\pgfdeclareimage[width=1cm]{dave}{dave}
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+\pgfdeclareimage[width=1cm]{eve}{eve}
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+\pgfdeclareimage[width=1.25cm]{mallory}{mallory}
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+\pgfdeclareimage[width=4cm]{bubble}{bubble1}
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+\pgfdeclareimage[width=0.5cm]{lock}{lock}
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+\pgfdeclareimage[width=2cm]{key}{key-sec}
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+\pgfdeclareimage[width=1.25cm]{apri}{alice-pri}
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+\pgfdeclareimage[width=1.25cm]{bpri}{bob-pri}
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+\pgfdeclareimage[width=1.25cm]{mpri}{mallory-pri}
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+\pgfdeclareimage[width=1.25cm]{apub}{alice-pub}
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+\pgfdeclareimage[width=1.25cm]{bpub}{bob-pub}
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+\pgfdeclareimage[width=1.25cm]{mpub}{mallory-pub}
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+\pgfdeclareimage[width=1cm]{ciphertext}{ciphertext}
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+\pgfdeclareimage[height=0.5cm]{x}{x}
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+\pgfdeclareimage[height=2.5cm]{crysp}{crysp}
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+
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+\newcommand\onenetwork{
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+ \filldraw [fill=orange!20, draw=black, thick] (-7,1) -- (-3.5,.5) -- (-4,-2) -- (-7,-2) -- cycle;
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+ \node [inner sep=0pt] (mobile) at (-5,-1.25) {\pgfuseimage{mobile}};
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+ \node [inner sep=0pt] (desktop) at (-6.5,-1.25) {\pgfuseimage{desktop}};
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+ \node [inner sep=0pt] (basestation) at (-4.25,-.25) {\pgfuseimage{basestation}};
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+ \node [inner sep=0pt] (AS1r1) at (-6,0.25) {\pgfuseimage{router}};
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+ \draw [draw=black,thick] (desktop) -- (basestation);
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+ \draw [draw=black,thick] (basestation) -- (AS1r1);
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+}
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+
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+\newcommand\theinternet{
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+ \filldraw [fill=green!20, draw=black, thick] (-5,4) -- (5,4) -- (3,1) -- (-3,1) -- cycle;
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+ \filldraw [fill=blue!20, draw=black, thick] (-3,.5) -- (3,.5) -- (3.5,-2) -- (-3.5,-2) -- cycle;
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+ \filldraw [fill=red!20, draw=black, thick] (-7,4) --(-5.5,4) -- (-3.5,1) -- (-7,1.5);
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+ \filldraw [fill=purple!20, draw=black, thick] (7,4) --(5.5,4) -- (3.5,1) -- (7,0);
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+ \filldraw [fill=orange!20, draw=black, thick] (-7,1) -- (-3.5,.5) -- (-4,-2) -- (-7,-2);
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+ \filldraw [fill=yellow!20, draw=black, thick] (7,-.5) -- (3.5,.5) -- (4,-2) -- (7,-2);
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+ \node [inner sep=0pt] (mobile) at (-5,-1.25) {\pgfuseimage{mobile}};
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+ \node [inner sep=0pt] (desktop) at (-6.5,-1.25) {\pgfuseimage{desktop}};
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+ \node [inner sep=0pt] (basestation) at (-4.25,-.25) {\pgfuseimage{basestation}};
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+ \node [inner sep=0pt] (AS1r1) at (-6,0.25) {\pgfuseimage{router}};
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+ \draw [draw=black,thick] (desktop) -- (basestation);
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+ \draw [draw=black,thick] (basestation) -- (AS1r1);
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+ \node [inner sep=0pt] (AS2r1) at (-6.25,2) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS2r3) at (-6.25,3.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS2r2) at (-4.6,1.6) {\pgfuseimage{router}};
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+ \draw [draw=black,thick] (AS2r1) -- (AS1r1);
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+ \draw [draw=black,thick] (AS2r2) -- (AS2r1);
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+ \draw [draw=black,thick] (AS2r2) -- (AS2r3);
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+ \draw [draw=black,thick] (AS2r1) -- (AS2r3);
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+ \draw [draw=black,thick] (AS2r1) -- ($(-7,1)!(AS2r1)!(-7,0)$);
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+ \draw [draw=black,thick] (AS2r3) -- ($(-7,1)!(AS2r3)!(-7,0)$);
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+ \node [inner sep=0pt] (AS3r1) at (-3.5,3.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS3r2) at (-2.5,1.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS3r3) at (-1,2.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS3r4) at (2,1.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS3r5) at (3,3) {\pgfuseimage{router}};
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+ \draw [draw=black,thick] (AS2r3) -- (AS3r1);
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+ \draw [draw=black,thick] (AS2r2) -- (AS3r2);
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+ \draw [draw=black,thick] (AS3r1) -- (AS3r3);
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+ \draw [draw=black,thick] (AS3r2) -- (AS3r3);
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+ \draw [draw=black,thick] (AS3r4) -- (AS3r3);
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+ \draw [draw=black,thick] (AS3r5) -- (AS3r3);
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+ \draw [draw=black,thick] (AS3r2) -- (AS3r4);
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+ \node [inner sep=0pt] (AS4r1) at (6.25,3.5) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS4r2) at (4.75,1.25) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS4basestation) at (6.25,1.2) {\pgfuseimage{basestation}};
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+ \draw [draw=black,thick] (AS4r1) -- (AS4r2);
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+ \draw [draw=black,thick] (AS4basestation) -- (AS4r2);
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+ \draw [draw=black,thick] (AS3r5) -- (AS4r1);
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+ \node [inner sep=0pt] (AS5r1) at (-2.5,0) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS5r2) at (2,0) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (AS5server) at (-1,-1) {\pgfuseimage{server}};
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+ \draw [draw=black,thick] (AS2r2) -- (AS5r1);
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+ \draw [draw=black,thick] (AS3r2) -- (AS5r1);
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+ \draw [draw=black,thick] (AS3r4) -- (AS5r2);
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+ \draw [draw=black,thick] (AS5r1) -- (AS5r2);
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+ \draw [draw=black,thick] (AS5r1) -- (AS5server);
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+ \node [inner sep=0pt] (AS6r1) at (4.3,-.3) {\pgfuseimage{router}};
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+ \node [inner sep=0pt] (server) at (6,-1.2) {\pgfuseimage{server}};
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+ \draw [draw=black,thick] (AS6r1) -- (AS4r2);
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+ \draw [draw=black,thick] (AS6r1) -- (server);
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+}
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+
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+\begin{document}
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+
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+\frame[plain]{\titlepage}
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+
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+\begin{frame}
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+ \frametitle{Introductions}
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+ \begin{itemize}
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+ \item My name is Vecna
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+ \item My pronouns are they/them
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+ \item I'm part of the Cryptography, Security, and Privacy (CrySP)\footnote{\url{https://crysp.org}} group
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+ \item My research focuses on privacy and censorship circumvention
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+ \item \textbf{Please interrupt me if you have questions}
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+ \end{itemize}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \node (crysp) {\pgfuseimage{crysp}};
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+ \end{tikzpicture}
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+ }
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Introductions}
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+ \begin{itemize}
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+ \item Introduce yourself
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+ \item Examples of what to say (if you want)
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+ \begin{itemize}
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+ \item Name
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+ \item Pronouns
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+ \item Something you're passionate about/interested in
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+ \item Why you wanted to come to SPARCS
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+ \item If you prefer to work in groups or alone
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+ \begin{itemize}
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+ \item We'll be playing a puzzle game
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+ \item You're welcome to work together or alone
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+ \item If you want a teammate/group, this may be a time to find one
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+ \end{itemize}
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+ \end{itemize}
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+ \end{itemize}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Introductions}
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+ \begin{itemize}
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+ \item Finally, let's introduce our characters...
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+ \vspace{1em}
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+ \begin{columns}
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+ \column{0.5\textwidth}
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+ \large Our friends
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+ \vspace{1em}
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+ \begin{columns}
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+ \column{0.5\textwidth}
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+ \pgfuseimage{alice} \large Alice
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+ \pgfuseimage{carol} \large Carol
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+ \column{0.5\textwidth}
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+ \pgfuseimage{bob} \large Bob
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+ \pgfuseimage{dave} \large Dave
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+ \end{columns}
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+ \column{0.5\textwidth}
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+ \large Our enemies
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+ \vspace{1em}
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+
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+ \pgfuseimage{eve} \large Eve \small (an eavesdropper)
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+ \pgfuseimage{mallory} \large Mallory \small (a malicious attacker)
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+ \end{columns}
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+
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+ \vspace{1em}
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+ \item These characters are common in cryptography/security
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+ \item These drawings are by Simon Oya\footnote{\url{https://simonoya.com/}}
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+ \end{itemize}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Goals}
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+ \begin{itemize}
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+ \item \textit{\textbf{Define}} the foundations of computer networks
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+ \item \textit{\textbf{Define}} security goals
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+ \item \textit{\textbf{Explore}} whether these security goals are accomplished on the Internet
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+ \item \textit{\textbf{Execute}} attacks against a (simulated) network
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+ \item \textit{\textbf{Identify}} real-world implications and defenses
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+ \end{itemize}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Outline}
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+ \begin{itemize}
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+ \item Networking background
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+ \begin{itemize}
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+ \item Introduction to networking/the Internet: \textbf{2 levels}
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+ \item ICMP (ping): \textbf{3 levels}
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+ \end{itemize}
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+ \item Security goals (and how the Internet fails to accomplish them)
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+ \begin{itemize}
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+ \item What are our security goals?
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+ \item Encryption: \textbf{1 level}
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+ \item Attacks: \textbf{6 levels}
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+ \end{itemize}
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+ \item Real-world implications
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+ \end{itemize}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{What is a Network?}
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+ \begin{itemize}
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+ \item Computers connected to each other
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+ \end{itemize}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \onenetwork
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+ \end{tikzpicture}
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+ }
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{What is the Internet?}
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+ \begin{itemize}
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+ \item A network of networks that connects computers across the world
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+ \end{itemize}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \theinternet
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+ \end{tikzpicture}
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+ }
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Packets}
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+ \begin{columns}
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+ \column{0.4\textwidth}
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+ \begin{itemize}
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+ \item Computers talk to each other using packets
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+ \item Think of a postcard with
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+ \begin{itemize}
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+ \item \color{\srccolor} Source address
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+ \item \color{\dstcolor} Destination address
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+ \item \color{\msgcolor} Message
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+ \end{itemize}
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+ \end{itemize}
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+ \column{0.6\textwidth}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \node (postcard) {\pgfuseimage{postcard}};
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+ \node at (-2.25,1.5) {\color{\srccolor}\large Alice's PC};
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+ \node at (2.35,0.55) {\color{\dstcolor}\large catpics.com};
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+ \node[text width=4cm] at (-1.85,-.5) {\color{\msgcolor}\large please send cat pics thx};
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+ \end{tikzpicture}
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+ }
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+ \end{columns}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Sending a Packet}
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+ \begin{itemize}
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+ \item Alice sends this packet to catpics.com and gets a response
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+ \end{itemize}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \theinternet
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+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
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+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
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+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
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+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
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+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
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+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
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+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
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+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
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+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
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+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
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+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
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+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
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+ \end{tikzpicture}
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+ }
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Response Packet}
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+ \begin{columns}
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+ \column{0.4\textwidth}
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+ \begin{itemize}
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+ \item Again, think of a postcard with
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+ \begin{itemize}
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+ \item \color{\srccolor} Source address
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+ \item \color{\dstcolor} Destination address
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+ \item \color{\msgcolor} Message
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+ \end{itemize}
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+ \end{itemize}
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+ \column{0.6\textwidth}
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+ \centerline{
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+ \begin{tikzpicture}
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+ \node (postcard) {\pgfuseimage{postcard}};
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+ \node at (-2.25,1.5) {\color{\srccolor}\large catpics.com};
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+ \node at (2.35,0.55) {\color{\dstcolor}\large Alice's PC};
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+ \draw [draw=\msgcolor, line width=3pt] (-3.5,0.5) -- (0,0.5) -- (0,-2) -- (-3.5,-2) -- cycle;
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+ \node at (-1.75,-.75) {\pgfuseimage{cat}};
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+ \end{tikzpicture}
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+ }
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+ \end{columns}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Takeaways}
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+ \begin{itemize}
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+ \item The Internet is just computers across the world talking to each other
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+ \item Computers send information back and forth in the form of packets
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+ \item Packets are like postcards
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+ \begin{itemize}
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+ \item Source address
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+ \item Destination address
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+ \item Message
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+ \item (all visible)
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+ \end{itemize}
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+ \end{itemize}
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+\end{frame}
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+
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+\begin{frame}
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+ \frametitle{Netsim}
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+ \begin{itemize}
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+ \item In this session, we will be playing a game called netsim
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+ \item This game provides a (simplified) simulation of a network to help you learn about networking and security
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+
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+ \item \textbf{Your task: Register and complete levels 1 -- 5}
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+ \begin{itemize}
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+ \item Register at \footnotesize\url{https://vvecna.cs.uwaterloo.ca/netsim/}\normalsize
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+ \item (Backup link: \footnotesize\url{https://netsim.erinn.io/}\normalsize)
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+ \item Accounts are not saved long-term (sorry)
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+ \item Feel free to work together or alone
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+ \item Ask if you need help
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+ \end{itemize}
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+ \end{itemize}
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+\end{frame}
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+\begin{frame}
|
|
|
+ \frametitle{Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \sout{\textit{\textbf{Define}} the foundations of computer networks}
|
|
|
+ \item \textit{\textbf{Define}} security goals
|
|
|
+ \item \textit{\textbf{Explore}} whether these security goals are accomplished on the Internet
|
|
|
+ \item \textit{\textbf{Execute}} attacks against a (simulated) network
|
|
|
+ \item \textit{\textbf{Identify}} real-world implications and defenses
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
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+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality
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|
+ \item Integrity
|
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|
+ \item Availability
|
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|
+ \item Authentication
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
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+
|
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|
+\begin{frame}
|
|
|
+ \frametitle{Failing to Meet Our Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Suppose Alice sends a message to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
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|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (msg) at (0,0) {\pgfuseimage{scroll}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Failing to Meet Our Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Suppose Alice sends a message to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (msg) at (0,0) {\pgfuseimage{scroll}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item \textbf{Confidentiality: Protecting data from unauthorized access}
|
|
|
+ \item Compromise of confidentiality: Eve reads the message
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Failing to Meet Our Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Suppose Alice sends a message to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \draw [-stealth] (alice) -- (mallory);
|
|
|
+ \draw [-stealth] (mallory) -- (bob);
|
|
|
+ \node [inner sep=0pt] (msg) at (-2,0) {\pgfuseimage{scroll}};
|
|
|
+ \node [inner sep=0pt] (badmsg) at (2,0) {\pgfuseimage{evilscroll}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item \textbf{Integrity: Ensuring data is correct/unchanged}
|
|
|
+ \item Compromise of integrity: Mallory modifies the message
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Failing to Meet Our Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Suppose Alice sends a message to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,1) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (block) at (0,0) {\pgfuseimage{x}};
|
|
|
+ \draw [-stealth] (alice) -- (block);
|
|
|
+ \node [inner sep=0pt] (msg) at (-2,0) {\pgfuseimage{scroll}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item \textbf{Availability: Ensuring data/system can be used correctly}
|
|
|
+ \item Compromise of availability: Mallory prevents Alice from sending the message to Bob
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Failing to Meet Our Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Suppose Mallory sends a message to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (mallory) at (-4,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (mallory) -- (bob);
|
|
|
+ \node [inner sep=0pt] (msg) at (0,0) {\pgfuseimage{evilscroll}};
|
|
|
+ \filldraw [fill=red, draw=black, thick] (-4,-0.65) -- (-4.75,-0.65) -- (-4.75,-0.25) -- (-4,-0.25) -- cycle;
|
|
|
+ \node[text width=2.5cm,color=white] at (-3.425,-0.35) {\tiny \textbf{HELLO}};
|
|
|
+ \node[text width=1.5cm,color=white] at (-4.12,-0.55) {\fontsize{3}{1} \textbf{MY\hspace{2px}NAME\hspace{2px}IS}};
|
|
|
+ \filldraw [fill=white, draw=black, thick] (-4,-0.65) -- (-4.75,-0.65) -- (-4.75,-1) -- (-4,-1) -- cycle;
|
|
|
+ \node[text width=2.5cm,color=black] at (-3.35,-0.85) {\tiny \textit{Alice}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item \textbf{Authentication: Ensuring data \textit{source} is correct}
|
|
|
+ \item Compromise of authentication: Mallory forges a message from Alice
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \sout{\textit{\textbf{Define}} the foundations of computer networks}
|
|
|
+ \item \sout{\textit{\textbf{Define}} security goals}
|
|
|
+ \item \textit{\textbf{Explore}} whether these security goals are accomplished on the Internet
|
|
|
+ \item \textit{\textbf{Execute}} attacks against a (simulated) network
|
|
|
+ \item \textit{\textbf{Identify}} real-world implications and defenses
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality: Protecting data from unauthorized access
|
|
|
+ \item Integrity: Ensuring data is correct/unchanged
|
|
|
+ \item Availability: Ensuring data/system is available
|
|
|
+ \item Authentication: Ensuring data \textit{source} is correct
|
|
|
+ \item \textbf{The Internet was not designed with security in mind}
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (eve-bubble) at (-4.75,1) {\pgfuseimage{bubble}};
|
|
|
+ \node[text width=2.75cm] at (-5,1) {\small I can break confidentiality.};
|
|
|
+ \node [inner sep=0pt] (eve) at (-2,0) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (mallory-bubble) at (1.25,1) {\pgfuseimage{bubble}};
|
|
|
+ \node[text width=2.5cm] at (1.25,1) {\small I can break all of these.};
|
|
|
+ \node [inner sep=0pt] (mallory) at (4,0) {\pgfuseimage{mallory}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Confidentiality}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{read} the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \theinternet
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Confidentiality}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{read} the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \filldraw [fill=green!20, draw=black, thick] (-5,4) -- (5,4) -- (3,1) -- (-3,1) -- cycle;
|
|
|
+ \filldraw [fill=blue!20, draw=black, thick] (-3,.5) -- (3,.5) -- (3.5,-2) -- (-3.5,-2) -- cycle;
|
|
|
+ \filldraw [fill=red!20, draw=black, thick] (-7,4) --(-5.5,4) -- (-3.5,1) -- (-7,1.5);
|
|
|
+ \filldraw [fill=purple!20, draw=black, thick] (7,4) --(5.5,4) -- (3.5,1) -- (7,0);
|
|
|
+ \filldraw [fill=orange!20, draw=black, thick] (-7,1) -- (-3.5,.5) -- (-4,-2) -- (-7,-2);
|
|
|
+ \filldraw [fill=yellow!20, draw=black, thick] (7,-.5) -- (3.5,.5) -- (4,-2) -- (7,-2);
|
|
|
+ \node [inner sep=0pt] (mobile) at (-5,-1.25) {\pgfuseimage{mobile}};
|
|
|
+ \node [inner sep=0pt] (desktop) at (-6.5,-1.25) {\pgfuseimage{desktop}};
|
|
|
+ \node [inner sep=0pt] (basestation) at (-4.25,-.25) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS1r1) at (-6,0.25) {\pgfuseimage{eve}};
|
|
|
+ \draw [draw=black,thick] (desktop) -- (basestation);
|
|
|
+ \draw [draw=black,thick] (basestation) -- (AS1r1);
|
|
|
+ \node [inner sep=0pt] (AS2r1) at (-6.25,2) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS2r3) at (-6.25,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS2r2) at (-4.6,1.6) {\pgfuseimage{eve}};
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS1r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- ($(-7,1)!(AS2r1)!(-7,0)$);
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- ($(-7,1)!(AS2r3)!(-7,0)$);
|
|
|
+ \node [inner sep=0pt] (AS3r1) at (-3.5,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r2) at (-2.5,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS3r3) at (-1,2.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS3r4) at (2,1.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r5) at (3,3) {\pgfuseimage{eve}};
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- (AS3r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=black,thick] (AS3r1) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r4);
|
|
|
+ \node [inner sep=0pt] (AS4r1) at (6.25,3.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS4r2) at (4.75,1.25) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (AS4basestation) at (6.25,1.2) {\pgfuseimage{basestation}};
|
|
|
+ \draw [draw=black,thick] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS4basestation) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS4r1);
|
|
|
+ \node [inner sep=0pt] (AS5r1) at (-2.5,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5r2) at (2,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5server) at (-1,-1) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5server);
|
|
|
+ \node [inner sep=0pt] (AS6r1) at (4.3,-.3) {\pgfuseimage{eve}};
|
|
|
+
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (server) at (6,-1.2) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (server);
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item How can we defend against this?
|
|
|
+ \item Cryptography!
|
|
|
+ \begin{itemize}
|
|
|
+ \item crypto = hidden, secret
|
|
|
+ \item graphy = field of study
|
|
|
+ \item Encryption = using math to hide things
|
|
|
+ \item Cryptography = encryption and related things
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Recall Packets...}
|
|
|
+ \begin{columns}
|
|
|
+ \column{0.4\textwidth}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Like a \textbf{postcard} with...
|
|
|
+ \begin{itemize}
|
|
|
+ \item \color{\srccolor}{Source address}
|
|
|
+ \item \color{\dstcolor}{Destination address}
|
|
|
+
|
|
|
+ \item \color{\msgcolor}{Message}
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+ \column{0.6\textwidth}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node (postcard) {\pgfuseimage{postcard}};
|
|
|
+ \node at (-2.25,1.5) {\color{\srccolor}\large Alice's PC};
|
|
|
+
|
|
|
+ \node at (2.35,0.55) {\color{\dstcolor}\large Bob's PC};
|
|
|
+ \node[text width=4cm] at (-.5,-.5) {\color{\msgcolor}\large HI BOB};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \end{columns}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{We Can Encrypt the Message}
|
|
|
+ \begin{columns}
|
|
|
+ \column{0.4\textwidth}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \color{\srccolor}{Source address}
|
|
|
+ \item \color{\dstcolor}{Destination address}
|
|
|
+
|
|
|
+ \item \color{\msgcolor}{Encrypted message}
|
|
|
+ \end{itemize}
|
|
|
+ \column{0.6\textwidth}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node (postcard) {\pgfuseimage{postcard}};
|
|
|
+ \node at (-2.25,1.5) {\color{\srccolor}\large Alice's PC};
|
|
|
+
|
|
|
+ \node at (2.35,0.55) {\color{\dstcolor}\large Bob's PC};
|
|
|
+ \node[text width=4cm] at (-.5,-.5) {\color{\msgcolor}\large IJCPC};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \end{columns}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{More Like a Letter than a Postcard}
|
|
|
+ \begin{columns}
|
|
|
+ \column{0.4\textwidth}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \color{\srccolor}{Source address}
|
|
|
+ \item \color{\dstcolor}{Destination address}
|
|
|
+
|
|
|
+ \item \color{\msgcolor}{Message} \normalcolor (hidden in the sealed envelope)
|
|
|
+ \end{itemize}
|
|
|
+ \column{0.6\textwidth}
|
|
|
+ \centerline{
|
|
|
+ \hspace{2em}
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node at (0,0) (envelope) {\pgfuseimage{envelope}};
|
|
|
+ \node at (-2.5,0.25) {\color{\srccolor}\large Alice's PC};
|
|
|
+
|
|
|
+ \node at (-0.1,-0.5) {\color{\dstcolor}\large Bob's PC};
|
|
|
+ \node[text width=1cm,rotate=15,align=right] at (2.7,2.5) {\color{\msgcolor} HI BOB};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \end{columns}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Confidentiality without Encryption}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (msg) at (0,0) {\pgfuseimage{scroll}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-bubble) at (-2.5,3) {\pgfuseimage{bubble}};
|
|
|
+ \node[text width=2.5cm] at (-2.5,3) {I can read this!};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Ensuring Confidentiality with Encryption}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+
|
|
|
+
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Ensuring Confidentiality with Encryption}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,2) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-bubble) at (-2.5,3) {\pgfuseimage{bubble}};
|
|
|
+ \node[text width=2.5cm] at (-2.5,3) {\LARGE \textbf{?????}};
|
|
|
+
|
|
|
+
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{How Does Encryption Work?}
|
|
|
+ \begin{itemize}
|
|
|
+ \item We need a \textbf{key}
|
|
|
+ \begin{itemize}
|
|
|
+ \item This is just a random number
|
|
|
+ \end{itemize}
|
|
|
+ \item If the key is secure, the encryption should be secure
|
|
|
+ \begin{itemize}
|
|
|
+ \item Kerckhoffs's principle: The system should be secure if everything about the system except the key is public knowledge
|
|
|
+ \item (Or Shannon's maxim: ``The enemy knows the system")
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Example: Caesar Cipher}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What should our \textbf{key $k$} be?
|
|
|
+ \item Take the message, and replace each letter with the $k$th next letter in the alphabet
|
|
|
+ \item For example, if $k = 5$, then NETSIM $\rightarrow$ SJYXNR
|
|
|
+ \item Let's encrypt the word ``CRYPTOGRAPHY"
|
|
|
+ \item How do we decrypt?
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Example: Caesar Cipher}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What should our \textbf{key $k$} be? (0--25)
|
|
|
+ \item Take the message, and replace each letter with the $k$th next letter in the alphabet
|
|
|
+ \item For example, if $k = 5$, then NETSIM $\rightarrow$ SJYXNR
|
|
|
+ \item Let's encrypt the word ``CRYPTOGRAPHY"
|
|
|
+ \item How do we decrypt?
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Also using the key}
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Example: Caesar Cipher}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What should our \textbf{key $k$} be? (0--25)
|
|
|
+ \item Take the message, and replace each letter with the $k$th next letter in the alphabet
|
|
|
+ \item For example, if $k = 5$, then \texttt{NETSIM} $\rightarrow$ \texttt{SJYXNR}
|
|
|
+ \item Let's encrypt the word \texttt{CRYPTOGRAPHY}
|
|
|
+ \item How do we decrypt?
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Also using the key}
|
|
|
+ \end{itemize}
|
|
|
+ \item Why isn't this secure?
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Example: One-Time Pad}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if we used a separate Caesar cipher for each letter?
|
|
|
+ \item Let's encrypt the word \texttt{NETSIM} with
|
|
|
+ \begin{itemize}
|
|
|
+ \item $k_1 = 20$
|
|
|
+ \item $k_2 = 21$
|
|
|
+ \item $k_3 = 18$
|
|
|
+ \item $k_4 = 1$
|
|
|
+ \item $k_5 = 15$
|
|
|
+ \item $k_6 = 6$
|
|
|
+ \end{itemize}
|
|
|
+ \item \texttt{NETSIM} $\rightarrow$ \texttt{HZLTXS}
|
|
|
+ \item Is this secure?
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Example: One-Time Pad}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if we used a separate Caesar cipher for each letter?
|
|
|
+ \item Let's encrypt the word \texttt{NETSIM} with
|
|
|
+ \begin{itemize}
|
|
|
+ \item $k_1 = 20$
|
|
|
+ \item $k_2 = 21$
|
|
|
+ \item $k_3 = 18$
|
|
|
+ \item $k_4 = 1$
|
|
|
+ \item $k_5 = 15$
|
|
|
+ \item $k_6 = 6$
|
|
|
+ \end{itemize}
|
|
|
+ \item \texttt{NETSIM} $\rightarrow$ \texttt{HZLTXS}
|
|
|
+ \item Is this secure?
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Only if the key is NEVER reused}
|
|
|
+ \end{itemize}
|
|
|
+ \item Is this usable?
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Key Exchange}
|
|
|
+ \begin{itemize}
|
|
|
+ \item We have other (more complicated) cryptography that works if Alice and Bob reuse their key
|
|
|
+ \begin{itemize}
|
|
|
+ \item We won't be talking about how it works today
|
|
|
+ \item Sorry
|
|
|
+ \end{itemize}
|
|
|
+ \item How does Alice get the key to Bob?
|
|
|
+ \item Proposal:
|
|
|
+ \begin{enumerate}
|
|
|
+ \item Alice sends the key to Bob
|
|
|
+ \item Alice and Bob use the key to encrypt future messages
|
|
|
+ \end{enumerate}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Key Exchange Proposal}
|
|
|
+ \begin{enumerate}
|
|
|
+ \item Alice sends the key to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-shares-key) at (0,0) {\pgfuseimage{key}};
|
|
|
+
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item Alice and Bob use the key to encrypt future messages
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (alice-key) at (-6,0) {\pgfuseimage{key}};
|
|
|
+ \node [inner sep=0pt] (bob-key) at (6,0) {\pgfuseimage{key}};
|
|
|
+
|
|
|
+ \end{tikzpicture}
|
|
|
+ \item Why doesn't this work?
|
|
|
+ \end{enumerate}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Key Exchange Proposal}
|
|
|
+ \begin{enumerate}
|
|
|
+ \item Alice sends the key to Bob
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-shares-key) at (0,0) {\pgfuseimage{key}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \item Alice and Bob use the key to encrypt future messages
|
|
|
+
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (alice-key) at (-6,0) {\pgfuseimage{key}};
|
|
|
+ \node [inner sep=0pt] (bob-key) at (6,0) {\pgfuseimage{key}};
|
|
|
+ \node [inner sep=0pt] (eve-key) at (1.5,1) {\pgfuseimage{key}};
|
|
|
+ \end{tikzpicture}
|
|
|
+
|
|
|
+
|
|
|
+ \end{enumerate}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Instead, we have more cryptography!
|
|
|
+ \item With more keys
|
|
|
+ \item Alice has...
|
|
|
+ \begin{itemize}
|
|
|
+ \item Alice's public key
|
|
|
+ \item Alice's secret key
|
|
|
+ \end{itemize}
|
|
|
+ \item Bob has...
|
|
|
+ \begin{itemize}
|
|
|
+ \item Bob's public key
|
|
|
+ \item Bob's secret key
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Instead, we have more cryptography!
|
|
|
+ \item With more keys
|
|
|
+ \item Alice has...
|
|
|
+ \begin{itemize}
|
|
|
+ \item Alice's public key (for \textbf{encrypting} messages \textbf{for Alice})
|
|
|
+ \item Alice's secret key (for \textbf{decrypting} messages \textbf{for Alice})
|
|
|
+ \end{itemize}
|
|
|
+ \item Bob has...
|
|
|
+ \begin{itemize}
|
|
|
+ \item Bob's public key (for \textbf{encrypting} messages \textbf{for Bob})
|
|
|
+ \item Bob's secret key (for \textbf{decrypting} messages \textbf{for Bob})
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-share-pub) at (0,0) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (bob) -- (alice);
|
|
|
+ \node [inner sep=0pt] (bob-share-pub) at (0,0) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct-bob-key) at (0.95,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct-bob-key) at (0.95,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \draw [color=red] (0.5,0) ellipse (1.5cm and 1cm);
|
|
|
+ \draw [color=red] (bob-pri) ellipse (1cm and 0.5cm);
|
|
|
+ \node[text width=4cm] at (5,-1.5) {\footnotesize need this key to decrypt};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (bob) -- (alice);
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct-alice-key) at (0.95,0.25) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Let's see it visually...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (bob) -- (alice);
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct-alice-key) at (0.95,0.25) {\pgfuseimage{apub}};
|
|
|
+ \draw [color=red] (0.5,0) ellipse (1.5cm and 1cm);
|
|
|
+ \draw [color=red] (alice-pri) ellipse (1cm and 0.5cm);
|
|
|
+ \node[text width=4cm] at (-5,-1.5) {\footnotesize need this key to decrypt};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Public-Key Cryptography Exercise}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Your task: Complete level 6}
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct-bob-key) at (0.95,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Not default, can be accomplished with encryption}
|
|
|
+ \end{itemize}
|
|
|
+ \item Integrity
|
|
|
+ \item Availability
|
|
|
+ \item Authentication
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{No Authentication}
|
|
|
+ \begin{itemize}
|
|
|
+ \item No check that source is correct
|
|
|
+ \end{itemize}
|
|
|
+ \vspace{1em}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (mallory) at (-5,0) {\pgfuseimage{mallory}};
|
|
|
+ \node (postcard) {\pgfuseimage{postcard}};
|
|
|
+ \node at (-2.25,1.5) {\color{\srccolor}\large Alice's PC};
|
|
|
+ \node at (3.15,1.7) {\color{\protocolor}\footnotesize ICMP};
|
|
|
+ \node at (2.35,0.55) {\color{\dstcolor}\large catpics.com};
|
|
|
+ \node[text width=4cm] at (-.5,-.5) {\color{\msgcolor}\large PING};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Your task: Complete levels 7 and 8}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with encryption
|
|
|
+ \end{itemize}
|
|
|
+ \item Integrity
|
|
|
+ \item Availability
|
|
|
+ \item Authentication
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Not default, can be accomplished with cryptography}
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Integrity}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{modify} the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \theinternet
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Integrity}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{modify} the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \filldraw [fill=green!20, draw=black, thick] (-5,4) -- (5,4) -- (3,1) -- (-3,1) -- cycle;
|
|
|
+ \filldraw [fill=blue!20, draw=black, thick] (-3,.5) -- (3,.5) -- (3.5,-2) -- (-3.5,-2) -- cycle;
|
|
|
+ \filldraw [fill=red!20, draw=black, thick] (-7,4) --(-5.5,4) -- (-3.5,1) -- (-7,1.5);
|
|
|
+ \filldraw [fill=purple!20, draw=black, thick] (7,4) --(5.5,4) -- (3.5,1) -- (7,0);
|
|
|
+ \filldraw [fill=orange!20, draw=black, thick] (-7,1) -- (-3.5,.5) -- (-4,-2) -- (-7,-2);
|
|
|
+ \filldraw [fill=yellow!20, draw=black, thick] (7,-.5) -- (3.5,.5) -- (4,-2) -- (7,-2);
|
|
|
+ \node [inner sep=0pt] (mobile) at (-5,-1.25) {\pgfuseimage{mobile}};
|
|
|
+ \node [inner sep=0pt] (desktop) at (-6.5,-1.25) {\pgfuseimage{desktop}};
|
|
|
+ \node [inner sep=0pt] (basestation) at (-4.25,-.25) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS1r1) at (-6,0.25) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (desktop) -- (basestation);
|
|
|
+ \draw [draw=black,thick] (basestation) -- (AS1r1);
|
|
|
+ \node [inner sep=0pt] (AS2r1) at (-6.25,2) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS2r3) at (-6.25,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS2r2) at (-4.6,1.6) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS1r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- ($(-7,1)!(AS2r1)!(-7,0)$);
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- ($(-7,1)!(AS2r3)!(-7,0)$);
|
|
|
+ \node [inner sep=0pt] (AS3r1) at (-3.5,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r2) at (-2.5,1.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS3r3) at (-1,2.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS3r4) at (2,1.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r5) at (3,3) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- (AS3r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=black,thick] (AS3r1) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r4);
|
|
|
+ \node [inner sep=0pt] (AS4r1) at (6.25,3.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS4r2) at (4.75,1.25) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS4basestation) at (6.25,1.2) {\pgfuseimage{basestation}};
|
|
|
+ \draw [draw=black,thick] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS4basestation) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS4r1);
|
|
|
+ \node [inner sep=0pt] (AS5r1) at (-2.5,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5r2) at (2,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5server) at (-1,-1) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5server);
|
|
|
+ \node [inner sep=0pt] (AS6r1) at (4.3,-.3) {\pgfuseimage{mallory}};
|
|
|
+
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (server) at (6,-1.2) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (server);
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with encryption
|
|
|
+ \end{itemize}
|
|
|
+ \item Integrity
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Not default, can be accomplished with cryptography}
|
|
|
+ \end{itemize}
|
|
|
+ \item Availability
|
|
|
+ \item Authentication
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with cryptography
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Availability}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{block} (or drop) the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \theinternet
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Attacking Availability}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Who can \textbf{block} (or drop) the message?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \filldraw [fill=green!20, draw=black, thick] (-5,4) -- (5,4) -- (3,1) -- (-3,1) -- cycle;
|
|
|
+ \filldraw [fill=blue!20, draw=black, thick] (-3,.5) -- (3,.5) -- (3.5,-2) -- (-3.5,-2) -- cycle;
|
|
|
+ \filldraw [fill=red!20, draw=black, thick] (-7,4) --(-5.5,4) -- (-3.5,1) -- (-7,1.5);
|
|
|
+ \filldraw [fill=purple!20, draw=black, thick] (7,4) --(5.5,4) -- (3.5,1) -- (7,0);
|
|
|
+ \filldraw [fill=orange!20, draw=black, thick] (-7,1) -- (-3.5,.5) -- (-4,-2) -- (-7,-2);
|
|
|
+ \filldraw [fill=yellow!20, draw=black, thick] (7,-.5) -- (3.5,.5) -- (4,-2) -- (7,-2);
|
|
|
+ \node [inner sep=0pt] (mobile) at (-5,-1.25) {\pgfuseimage{mobile}};
|
|
|
+ \node [inner sep=0pt] (desktop) at (-6.5,-1.25) {\pgfuseimage{desktop}};
|
|
|
+ \node [inner sep=0pt] (basestation) at (-4.25,-.25) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS1r1) at (-6,0.25) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (desktop) -- (basestation);
|
|
|
+ \draw [draw=black,thick] (basestation) -- (AS1r1);
|
|
|
+ \node [inner sep=0pt] (AS2r1) at (-6.25,2) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS2r3) at (-6.25,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS2r2) at (-4.6,1.6) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS1r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- (AS2r3);
|
|
|
+ \draw [draw=black,thick] (AS2r1) -- ($(-7,1)!(AS2r1)!(-7,0)$);
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- ($(-7,1)!(AS2r3)!(-7,0)$);
|
|
|
+ \node [inner sep=0pt] (AS3r1) at (-3.5,3.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r2) at (-2.5,1.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS3r3) at (-1,2.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS3r4) at (2,1.5) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS3r5) at (3,3) {\pgfuseimage{mallory}};
|
|
|
+ \draw [draw=black,thick] (AS2r3) -- (AS3r1);
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=black,thick] (AS3r1) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS3r3);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS3r4);
|
|
|
+ \node [inner sep=0pt] (AS4r1) at (6.25,3.5) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS4r2) at (4.75,1.25) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (AS4basestation) at (6.25,1.2) {\pgfuseimage{basestation}};
|
|
|
+ \draw [draw=black,thick] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS4basestation) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS3r5) -- (AS4r1);
|
|
|
+ \node [inner sep=0pt] (AS5r1) at (-2.5,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5r2) at (2,0) {\pgfuseimage{router}};
|
|
|
+ \node [inner sep=0pt] (AS5server) at (-1,-1) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS2r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r2) -- (AS5r1);
|
|
|
+ \draw [draw=black,thick] (AS3r4) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5r2);
|
|
|
+ \draw [draw=black,thick] (AS5r1) -- (AS5server);
|
|
|
+ \node [inner sep=0pt] (AS6r1) at (4.3,-.3) {\pgfuseimage{mallory}};
|
|
|
+
|
|
|
+
|
|
|
+ \node [inner sep=0pt] (server) at (6,-1.2) {\pgfuseimage{server}};
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=black,thick] (AS6r1) -- (server);
|
|
|
+ \node [inner sep=0pt] (alice) at (-7.65,-1.25) {\pgfuseimage{alice}};
|
|
|
+ \draw [draw=red,line width=3pt] (desktop) -- (basestation);
|
|
|
+ \draw [draw=red,line width=3pt] (basestation) -- (AS1r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS1r1) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS2r1);
|
|
|
+ \draw [draw=red,line width=3pt] (AS2r2) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS3r3) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS3r5);
|
|
|
+ \draw [draw=red,line width=3pt] (AS4r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (AS4r2);
|
|
|
+ \draw [draw=red,line width=3pt] (AS6r1) -- (server);
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Another Attack on Availability}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Denial of Service (DoS)
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (mallory) at (-5,0) {\pgfuseimage{mallory}};
|
|
|
+ \node (postcard) {\pgfuseimage{postcard}};
|
|
|
+ \node at (-2.25,1.5) {\color{\srccolor}\large Mallory's PC};
|
|
|
+ \node at (3.15,1.7) {\color{\protocolor}\footnotesize ICMP};
|
|
|
+ \node at (2.35,0.55) {\color{\dstcolor}\large catpics.com};
|
|
|
+ \node[text width=4cm] at (-.5,-.5) {\color{\msgcolor}\large PING};
|
|
|
+ \node[text width=2.5cm] at (5.5,-2) {\LARGE x1000};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Your task: Complete levels 9, 10, and 11}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Security Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Confidentiality
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with encryption
|
|
|
+ \end{itemize}
|
|
|
+ \item Integrity
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with cryptography
|
|
|
+ \end{itemize}
|
|
|
+ \item Availability
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Not default, can be partially accomplished with firewalls}
|
|
|
+ \end{itemize}
|
|
|
+ \item Authentication
|
|
|
+ \begin{itemize}
|
|
|
+ \item Not default, can be accomplished with cryptography
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Takeaways}
|
|
|
+ \begin{itemize}
|
|
|
+ \item The Internet was not designed with security in mind
|
|
|
+ \item We accomplish \textbf{none} of our security goals by default
|
|
|
+ \item We can hack on security sometimes, usually through cryptography
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Recall public-key encryption...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Recall public-key encryption...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-share-pub) at (0,0) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Recall public-key encryption...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (bob) -- (alice);
|
|
|
+ \node [inner sep=0pt] (bob-share-pub) at (0,0) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Recall public-key encryption...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (alice) -- (bob);
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-ct-bob-key) at (0.95,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Recall public-key encryption...
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-bob-pub) at (-5.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-pub) at (5.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \draw [-stealth] (bob) -- (alice);
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct) at (0,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (bob-alice-ct-alice-key) at (0.95,0.25) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve) at (0,1.5) {\pgfuseimage{eve}};
|
|
|
+ \node [inner sep=0pt] (eve-alice-pub) at (-1.5,1.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (eve-bob-pub) at (1.5,1.5) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (alice) -- (mallory);
|
|
|
+ \node [inner sep=0pt] (alice-share-pub) at (-2,0) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (mallory-alice-pub) at (-0.75,2) {\pgfuseimage{apub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (alice) -- (mallory);
|
|
|
+ \node [inner sep=0pt] (alice-share-pub) at (-2,0) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (mallory-alice-pub) at (-0.75,2) {\pgfuseimage{apub}};
|
|
|
+ \draw [-stealth] (mallory) -- (bob);
|
|
|
+ \node [inner sep=0pt] (mallory-share-pub) at (2,0) {\pgfuseimage{mpub}};
|
|
|
+ \node [text width=4cm] at (2.75,-1) {``from Alice"};
|
|
|
+ \node [inner sep=0pt] (bob-mallory-pub) at (5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (bob) -- (mallory);
|
|
|
+ \node [inner sep=0pt] (bob-share-pub) at (2,0) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (mallory-alice-pub) at (-0.75,2) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (mallory-bob-pub) at (0.75,2) {\pgfuseimage{bpub}};
|
|
|
+ \draw [-stealth] (mallory) -- (alice);
|
|
|
+ \node [inner sep=0pt] (mallory-share-pub) at (-2,0) {\pgfuseimage{mpub}};
|
|
|
+ \node [text width=4cm] at (-1.25,-1) {``from Bob"};
|
|
|
+ \node [inner sep=0pt] (bob-mallory-pub) at (5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \node [inner sep=0pt] (alice-mallory-pub) at (-5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (alice) -- (mallory);
|
|
|
+ \node [inner sep=0pt] (alice-mallory-ct) at (-2.5,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-mallory-ct-mallory-key) at (-1.55,0.25) {\pgfuseimage{mpub}};
|
|
|
+ \node [inner sep=0pt] (mallory-alice-pub) at (-0.75,2) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (mallory-bob-pub) at (0.75,2) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-mallory-pub) at (5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \node [inner sep=0pt] (alice-mallory-pub) at (-5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (mallory) -- (bob);
|
|
|
+ \node [inner sep=0pt] (mallory-bob-ct) at (1.5,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (mallory-bob-ct-mallory-key) at (2.45,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Mallory-in-the-Middle}
|
|
|
+ \begin{itemize}
|
|
|
+ \item What if our enemy does more than just eavesdrop?
|
|
|
+ \end{itemize}
|
|
|
+ \centerline{
|
|
|
+ \begin{tikzpicture}
|
|
|
+ \node [inner sep=0pt] (alice) at (-4,0) {\pgfuseimage{alice}};
|
|
|
+ \node [inner sep=0pt] (alice-pub) at (-5.5,0.5) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (alice-pri) at (-5.5,-0.5) {\pgfuseimage{apri}};
|
|
|
+ \node [inner sep=0pt] (bob) at (4,0) {\pgfuseimage{bob}};
|
|
|
+ \node [inner sep=0pt] (bob-pub) at (5.5,0.5) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-pri) at (5.5,-0.5) {\pgfuseimage{bpri}};
|
|
|
+ \node [inner sep=0pt] (mallory) at (0,0) {\pgfuseimage{mallory}};
|
|
|
+ \node [inner sep=0pt] (mallory-pri) at (-0.75,1) {\pgfuseimage{mpri}};
|
|
|
+ \node [inner sep=0pt] (mallory-pub) at (0.75,1) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (alice) -- (mallory);
|
|
|
+ \node [inner sep=0pt] (alice-mallory-ct) at (-2.5,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (alice-mallory-ct-mallory-key) at (-1.55,0.25) {\pgfuseimage{mpub}};
|
|
|
+ \node [inner sep=0pt] (mallory-alice-pub) at (-0.75,2) {\pgfuseimage{apub}};
|
|
|
+ \node [inner sep=0pt] (mallory-bob-pub) at (0.75,2) {\pgfuseimage{bpub}};
|
|
|
+ \node [inner sep=0pt] (bob-mallory-pub) at (5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \node [inner sep=0pt] (alice-mallory-pub) at (-5.5,1.5) {\pgfuseimage{mpub}};
|
|
|
+ \draw [-stealth] (mallory) -- (bob);
|
|
|
+ \node [inner sep=0pt] (mallory-bob-ct) at (1.5,0) {\pgfuseimage{ciphertext}};
|
|
|
+ \node [inner sep=0pt] (mallory-bob-ct-mallory-key) at (2.45,0.25) {\pgfuseimage{bpub}};
|
|
|
+ \end{tikzpicture}
|
|
|
+ }
|
|
|
+ \begin{itemize}
|
|
|
+ \item \textbf{Your task: Complete level 12}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Wrapping Up Cryptography}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Cryptography lets us do more than just hide things
|
|
|
+ \begin{itemize}
|
|
|
+ \item We can ensure integrity of data (has it changed?)
|
|
|
+ \item We can ensure authenticity of data (who wrote it?)
|
|
|
+ \end{itemize}
|
|
|
+ \item We won't talk about it more than that right now
|
|
|
+ \item But it's very cool!
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \sout{\textit{\textbf{Define}} the foundations of computer networks}
|
|
|
+ \item \sout{\textit{\textbf{Define}} security goals}
|
|
|
+ \item \sout{\textit{\textbf{Explore}} whether these security goals are accomplished on the Internet}
|
|
|
+ \item \sout{\textit{\textbf{Execute}} attacks against a (simulated) network}
|
|
|
+ \item \textit{\textbf{Identify}} real-world implications and defenses
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Real-World Implications}
|
|
|
+ \begin{itemize}
|
|
|
+ \item These simulated attacks have real-world implications
|
|
|
+ \begin{itemize}
|
|
|
+ \item The Internet was not designed with security in mind
|
|
|
+ \item Security had to be hacked on later
|
|
|
+ \item Many parts of the Internet are still insecure by default
|
|
|
+ \item Considering security during design can help you later
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Real-World Implications}
|
|
|
+ \begin{itemize}
|
|
|
+ \item But things are getting better!
|
|
|
+ \begin{itemize}
|
|
|
+ \item Most web traffic is encrypted now with HTTPS
|
|
|
+ \begin{itemize}
|
|
|
+ \item (and integrity and authentication are guaranteed)
|
|
|
+ \end{itemize}
|
|
|
+ \item More instant messengers are using encryption
|
|
|
+ \end{itemize}
|
|
|
+ \item There's still room for improvement
|
|
|
+ \begin{itemize}
|
|
|
+ \item Protecting metadata:
|
|
|
+ \begin{itemize}
|
|
|
+ \item Which sites you visit
|
|
|
+ \item Which people you talk to
|
|
|
+ \end{itemize}
|
|
|
+ \item Censorship
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Real-World Things You Can Do}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Encrypt your web traffic
|
|
|
+ \begin{itemize}
|
|
|
+ \item You can set your web browser settings to use HTTPS everywhere\footnote{\url{https://www.eff.org/deeplinks/2021/09/https-actually-everywhere}}
|
|
|
+ \end{itemize}
|
|
|
+ \item Encrypt your private messages
|
|
|
+ \begin{itemize}
|
|
|
+ \item Signal\footnote{\url{https://signal.org/}} is easy to use and offers strong encryption
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Real-World Things You Can Do}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Hide which sites you visit and circumvent censorship
|
|
|
+ \begin{itemize}
|
|
|
+ \item Tor\footnote{\url{https://torproject.org/}} is better for privacy and anonymity for VPNs
|
|
|
+ \item Run the Snowflake\footnote{\url{https://snowflake.torproject.org/}} browser extension to help other people use Tor
|
|
|
+ \end{itemize}
|
|
|
+ \item Study cryptography, security, and/or privacy and help fix things
|
|
|
+ \begin{itemize}
|
|
|
+ \item Check out CrySP\footnote{\url{https://crysp.org/}} for the work we do here at UW
|
|
|
+ \end{itemize}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Goals}
|
|
|
+ \begin{itemize}
|
|
|
+ \item \sout{\textit{\textbf{Define}} the foundations of computer networks}
|
|
|
+ \item \sout{\textit{\textbf{Define}} security goals}
|
|
|
+ \item \sout{\textit{\textbf{Explore}} whether these security goals are accomplished on the Internet}
|
|
|
+ \item \sout{\textit{\textbf{Execute}} attacks against a (simulated) network}
|
|
|
+ \item \sout{\textit{\textbf{Identify}} real-world implications and defenses}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\begin{frame}
|
|
|
+ \frametitle{Closing}
|
|
|
+ \begin{itemize}
|
|
|
+ \item Congratulations! You have learned some things about networking, the insecurity of the Internet, and hacking
|
|
|
+ \item General advice:
|
|
|
+ \begin{itemize}
|
|
|
+ \item Privacy matters
|
|
|
+ \item Don't trust corporations
|
|
|
+ \item Please work on making the world better, not worse
|
|
|
+ \end{itemize}
|
|
|
+
|
|
|
+
|
|
|
+ \item This talk is available at \footnotesize \url{https://vvecna.cs.uwaterloo.ca/2024-uw-sparcs-netsim.pdf}
|
|
|
+ \end{itemize}
|
|
|
+\end{frame}
|
|
|
+
|
|
|
+\end{document}
|
