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% Adapt title information
% =======================
\title{GNU Taler \\ Payments for the Common Good}
\institute{The GNU Project}
%\author{Christian Grothoff \& Sva}
%\date{5.7.2017}

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% ====================
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 \usetikzlibrary{snakes}


\begin{document}

\begin{frame}
  \begin{center}
    GNU Taler: Payments for the Common Good

%    \includegraphics[width=0.66\textwidth]{logo-2017-fr.pdf}
    \includegraphics[width=0.66\textwidth]{taler-logo-2017.pdf}
  \end{center}
\begin{textblock*}{4cm}(.5cm,7.5cm) % {block width} (coords)
  {\Large {\bf \url{taler.net}} \\
%    IRC{\bf \#taler} \\
%   {\small (on freenode)} \\
    twitter@taler \\
    mail@taler.net }
\end{textblock*}

 \begin{textblock*}{4cm}(10cm,7.5cm) % {block width} (coords)
  \includegraphics[width=2cm]{ashoka.png}
\end{textblock*}

\end{frame}

\section{The Problem}
\begin{frame}{The Problem}

  3D secure (``verified by visa'') is a nightmare:
  \begin{minipage}{5cm}
    \begin{itemize}
    \item Complicated process
    \item Shifts liability to consumer
    \item Significant latency
    \item Can refuse valid requests
    \item Legal vendors excluded
    \item No privacy for buyers
     \end{itemize}
  \end{minipage}
  \begin{minipage}{5cm}
      \includegraphics[width=\textwidth]{illustrations/cc3ds.pdf}
  \end{minipage}
  \vfill
    Online credit card payments will be replaced, but with what?
\end{frame}


\begin{frame}{The Problem}
\vfill
  \begin{textblock*}{12cm}(0.5cm,1cm) % {block width} (coords)
    \begin{itemize}
    \item Global tech companies push oligopolies
    \item Privacy and federated finance are at risk
%    \item 30\% fees are conceivable
    \item Economic sovereingity is in danger
    \end{itemize}
\end{textblock*}
\begin{textblock*}{4cm}(3.5cm,5.2cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/amazon.png}}
\end{textblock*}
\begin{textblock*}{2cm}(7cm,3cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/alipay.jpeg}}
\end{textblock*}
\begin{textblock*}{2cm}(3cm,3.5cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/paypal.jpeg}}
\end{textblock*}
\begin{textblock*}{2cm}(9cm,5cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/applepay.jpeg}}
\end{textblock*}
\begin{textblock*}{2cm}(7.5cm,5.9cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/samsungpay.jpeg}}
\end{textblock*}
\begin{textblock*}{1cm}(9.5cm,6.3cm) % {block width} (coords)
 {\includegraphics[width=\textwidth]{competitor-logos/android_pay.png}}
\end{textblock*}
\vfill
\end{frame}


\section{What is GNU Taler?}
\begin{frame}{What is GNU Taler?}
  \vfill
  \begin{center}
GNU Taler is an electronic instant payment system.
  \end{center}
  \begin{itemize}
  \item Uses electronic coins stored in {\bf wallets} on customer's device
  \item Think electronic {\bf cash}, with a few twists
  \item Pay in {\bf existing currencies} (i.e. EUR, USD, BTC)
%    or use it to create new regional currencies
  \end{itemize}
  \vfill
  \begin{center}
    Taler is {\bf not} a cryptocurrency.
  \end{center}
\end{frame}


\begin{frame}
\frametitle{GNU Taler Overview}
\begin{center}
\begin{tikzpicture}
 \tikzstyle{def} = [node distance= 5em and 6.5em, inner sep=1em, outer sep=.3em];
 \node (origin) at (0,0) {};
 \node (exchange) [def,above=of origin,draw]{Exchange};
 \node (customer) [def, draw, below left=of origin] {Customer};
 \node (merchant) [def, draw, below right=of origin] {Merchant};
 \node (auditor) [def, draw, above right=of origin]{Auditor};

 \tikzstyle{C} = [color=black, line width=1pt]

 \draw [<-, C] (customer) -- (exchange) node [midway, above, sloped] (TextNode) {withdraw coins};
 \draw [<-, C] (exchange) -- (merchant) node [midway, above, sloped] (TextNode) {deposit coins};
 \draw [<-, C] (merchant) -- (customer) node [midway, above, sloped] (TextNode) {spend coins};
 \draw [<-, C] (exchange) -- (auditor) node [midway, above, sloped] (TextNode) {verify};

\end{tikzpicture}
\end{center}
\end{frame}
% Demo here


\begin{frame}{Social Impact of Taler}
  \begin{center}
    \includegraphics[height=0.8\textheight]{social-impact.pdf}
  \end{center}
\end{frame}


\begin{frame}
    \frametitle{Possible outcomes (optimistic)}
    \begin{itemize}
        \item{Replace Mastercard/Visa/Paypal online}
        \item[$\Rightarrow$]{Cheaper transactions $\equiv$ 3\% reduction in VAT}
        \item{Replace cash and credit cards}
        \item[$\Rightarrow$]{Faster business transactions in stores}
        \item{Income via Taler is easily tracked by the government}
        \item[$\Rightarrow$]{Less corruption, less tax evasion}
        \item{Banks \& Spy Agencies can no longer track how you spend your money}
        \item[$\Rightarrow$]{Privacy for citizens! Industrial espionage defense for business!}
    \end{itemize}
\end{frame}



\begin{frame}{}
  \vfill
  \begin{center}
    {Why should {\em governments} be interested?}
  \end{center}
  \vfill
  \begin{center}
  \includegraphics[height=3cm]{illustrations/usmint.jpeg}
  \end{center}
  \vfill
  \begin{center}
    {Why not do {\em online} what they do {\em offline}?\footnote{Just better: you can anonymously receive cash, but not Taler coins.}}
  \end{center}
\end{frame}



\begin{frame}
  \begin{center}
%    \includegraphics[width=0.66\textwidth]{logo-2017-fr.pdf}
    \includegraphics[width=0.66\textwidth]{taler-logo-2017.pdf}
  \end{center}
  \vfill
  \hfill A GNU package
\end{frame}

\section{Comparison}
\begin{frame}{Comparison}
  \begin{center} \small
    \begin{tabular}{l||c|c|c|c|c}
                & Cash & Bitcoin & ZCash    & Creditcard & GNU Taler \\ \hline \hline
    Online      &$-$$-$$-$  &   ++    &    ++    &     +      &   +++  \\ \hline
    Offline     & +++  &   $-$$-$    &    $-$$-$    &     +      &   $-$$-$  \\ \hline
    Trans. cost & +    & $-$$-$$-$   & $-$$-$$-$  &     $-$      &   ++  \\ \hline
    Speed       & +    & $-$$-$$-$   & $-$$-$$-$  &     o      &   ++  \\ \hline
    Taxation    & $-$    &   $-$$-$    &  $-$$-$$-$   &    +++     &  +++  \\ \hline
    Payer-anon  &  ++  &   o     &    ++    &  $-$$-$$-$   &  +++  \\ \hline
    Payee-anon  & ++   &   o     &    ++    &  $-$$-$$-$    &  $-$$-$$-$ {\bf (*)} \\ \hline
    Security    &  $-$   &   o     &    o     &    $-$$-$      &  ++   \\ \hline
    Conversion  & +++  &  $-$$-$$-$   & $-$$-$$-$ &    +++     &  +++  \\ \hline
    Libre       &  $-$   &  +++    &    +++   & $-$ $-$ $-$      &  +++  \\
  \end{tabular}
  \end{center}
  {{\bf (*)} Not having payee-anonymity is a good thing as otherwise money laundering
    becomes a real problem.}
\end{frame}


\end{document}