395 \only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Your mobile phone or creditcard/pin might 

   395 \only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Your mobile phone or credit card/pin might 

   438 voting machines safe.

   438 voting machines safe

   479 \only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Casual thiefs, insider attacks.\end{tabular}}

   479 \only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Casual thieves, insider attacks.\end{tabular}}

   488 \item<7>[]{\bf\large No!} {\textcolor{gray}{Though in some areas they work: airport.}}

   488 \item<7>[]{\bf\large No!} {\textcolor{gray}{Though in some areas they work: airport, swimming pool}}

   489 \end{itemize}

   489 \end{itemize}

   490 

   491 

   492 \end{frame}}

   493 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   494 

   495 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   496 \mode<presentation>{

   497 \begin{frame}[t]

   498 \frametitle{\begin{tabular}{@ {}c@ {}}Ex: Security by Obscurity\end{tabular}}

   499 

   500 You might think it is a good idea to keep a security relevant algorithm or 

   501 software secret.

   502 

   503 \begin{itemize}

   504 \item<1->What assets are you trying to protect?\\

   505 \only<1>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}source code, an algorithm\end{tabular}}

   506 \item<2->What are the risks to these assets?\\

   507 \only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright

   508 Can be pretty high (Oystercards).\end{tabular}}

   509 \item<3->How well does the security solution mitigate those risks?\\

   510 \only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright

   511 Not really. The source code can be reverse engineered, stolen\ldots{}\end{tabular}}

   512 \item<4->What other risks does the security solution cause?

   513 \only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright You prevent

   514 scrutiny and independent advice. You also more likely than not,

   515 get it wrong.\end{tabular}}

   516 \item<5>[]{\bf\large No!}

   517 \end{itemize}

   518 

   519 

   520 \end{frame}}

   521 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   522 

   523 

   524 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   525 \mode<presentation>{

   526 \begin{frame}[t]

   527 \frametitle{\begin{tabular}{@ {}c@ {}}Voting as Security Problem\end{tabular}}

   528 

   529 What are the security requirements of a voting system?\bigskip

   530 

   531 \begin{itemize}

   532 \item<2->Integrity 

   533 \item<3->Ballot Secrecy

   534 \item<5->Voter Authentication

   535 \item<6->Enfranchisement

   536 \item<7->Availability

   537 \end{itemize}

   538 

   539 \only<2>{

   540 \begin{textblock}{5.5}(8,5)

   541 \begin{tikzpicture}

   542 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   543 {\small

   544 \begin{minipage}{5cm}\raggedright

   545 \begin{center}

   546 \begin{minipage}{4.5cm}

   547 \begin{itemize}

   548 \item The outcome matches with the voter intend.

   549 \item There might be gigantic sums at stake.

   550 \end{itemize}

   551 \end{minipage}

   552 \end{center}

   553 \end{minipage}};

   554 \end{tikzpicture}

   555 \end{textblock}}

   556 

   557 \only<4>{

   558 \begin{textblock}{5.5}(8,5)

   559 \begin{tikzpicture}

   560 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   561 {\small

   562 \begin{minipage}{5cm}\raggedright

   563 \begin{center}

   564 \begin{minipage}{4.5cm}

   565 \begin{itemize}

   566 \item Nobody can find out how you voted.

   567 \item (Stronger) Even if you try, you cannot prove how you voted.

   568 \end{itemize}

   569 \end{minipage}

   570 \end{center}

   571 \end{minipage}};

   572 \end{tikzpicture}

   573 \end{textblock}}

   574 

   575 \only<5>{

   576 \begin{textblock}{5.5}(8,5)

   577 \begin{tikzpicture}

   578 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   579 {\small

   580 \begin{minipage}{5cm}\raggedright

   581 \begin{center}

   582 \begin{minipage}{4.5cm}

   583 \begin{itemize}

   584 \item Only authorised voters can vote up to the permitted number of votes.

   585 \end{itemize}

   586 \end{minipage}

   587 \end{center}

   588 \end{minipage}};

   589 \end{tikzpicture}

   590 \end{textblock}}

   591 

   592 \only<6>{

   593 \begin{textblock}{5.5}(8,5)

   594 \begin{tikzpicture}

   595 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   596 {\small

   597 \begin{minipage}{5cm}\raggedright

   598 \begin{center}

   599 \begin{minipage}{4.5cm}

   600 \begin{itemize}

   601 \item Only authorised voters should be able to vote up to the permitted number of votes.

   602 \end{itemize}

   603 \end{minipage}

   604 \end{center}

   605 \end{minipage}};

   606 \end{tikzpicture}

   607 \end{textblock}}

   608 

   609 \only<7>{

   610 \begin{textblock}{5.5}(8,5)

   611 \begin{tikzpicture}

   612 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   613 {\small

   614 \begin{minipage}{5cm}\raggedright

   615 \begin{center}

   616 \begin{minipage}{4.5cm}

   617 \begin{itemize}

   618 \item The voting system should accept all authorised votes and produce results in a timely manner.

   619 \end{itemize}

   620 \end{minipage}

   621 \end{center}

   622 \end{minipage}};

   623 \end{tikzpicture}

   624 \end{textblock}}

   625 

   626 \only<6>{

   627 \begin{textblock}{5.5}(8,5)

   628 \begin{tikzpicture}

   629 \draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] 

   630 {\small

   631 \begin{minipage}{5cm}\raggedright

   632 \begin{center}

   633 \begin{minipage}{4.5cm}

   634 \begin{itemize}

   635 \item Only authorised voters should be able to vote up to the permitted number of votes.

   636 \end{itemize}

   637 \end{minipage}

   638 \end{center}

   639 \end{minipage}};

   640 \end{tikzpicture}

   641 \end{textblock}}

   642 

   643 \end{frame}}

   644 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   645 

   646 

   647 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   648 \mode<presentation>{

   649 \begin{frame}[t]

   650 \frametitle{\begin{tabular}{@ {}c@ {}}Ballot Boxes\end{tabular}}

   651 

   652 

   653 \begin{center}

   654 \includegraphics[scale=2.5]{pics/ballotbox.jpg}

   655 \end{center}

   656 

   657 

   658 \end{frame}}

   659 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   660 

   661 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   662 \mode<presentation>{

   663 \begin{frame}[t]

   664 \frametitle{\begin{tabular}{@ {}c@ {}}Problems with Voting\end{tabular}}

   665 

   666 

   667 \begin{center}\large

   668 \begin{tabular}{rcl}

   669 Integrity & vs. & Ballot Secrecy\bigskip\\

   670 Authentication & vs. &Enfranchisement   

   671 \end{tabular}

   672 \end{center}\bigskip\bigskip\pause

   673 

   674 Further constraints:

   675 

   676 \begin{itemize}

   677 \item costs

   678 \item accessibility

   679 \item convenience

   680 \item intelligibility 

   681 \end{itemize}

   682 \end{frame}}

   683 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   684 

   685 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   686 \mode<presentation>{

   687 \begin{frame}[t]

   688 \frametitle{\begin{tabular}{@ {}c@ {}}E-Voting\end{tabular}}

   689 

   690 

   691 \begin{itemize}

   692 \item The Netherlands, between 1997 - 2006 had electronic voting machines\\

   693 \textcolor{gray}{(it has been found that they could be hacked and emitted radio signals)}

   694 

   695 \item Germany, had been used in pilot studies\\ 

   696 \textcolor{gray}{(in 2007 a law suit has reached the highest court and it rejected electronic voting

   697 on the grounds of not being understandable by the general public)}

   698 

   699 \item UK, used optical scan voting systems in a few polls

   700 \end{itemize}

   701 \end{frame}}

   702 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   703 

   704 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   705 \mode<presentation>{

   706 \begin{frame}[t]

   707 \frametitle{\begin{tabular}{@ {}c@ {}}E-Voting\end{tabular}}

   708 

   709 \mbox{}\\[-12mm]

   710 \begin{itemize}

   711 \item US, used mechanical machines since the 50s, later punch cards, DREs and 

   712 optical scan voting machines \textcolor{gray}{(fantastic ``ecosystem'' for research)}

   713 

   714 \item Estonia used in 2007 the world's first Internet vote in national elections (there are earlier pilot studies)

   715 

   716 \item India, the biggest democracy uses e-voting devices  since at least 2003\\

   717 \textcolor{gray}{(keep-it-simple machines produced by a government owned company)}

   718 

   719 \item South Africa used software for its tallying in the 1993 elections (Nelson Mandela)

   720 \textcolor{gray}{(they found the software was rigged, but they were able to manually tally)}

   721 \end{itemize}

   722 \end{frame}}

   723 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   724 

   725 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   726 \mode<presentation>{

   727 \begin{frame}[t]

   728 \frametitle{\begin{tabular}{@ {}c@ {}}A Brief History of Voting\end{tabular}}

   729 

   730 

   731 \begin{itemize}

   732 \item Athenians

   733 \begin{itemize}

   734 \item show of hands

   735 \item ballots on pieces of pottery

   736 \item different colours of stones

   737 \item ``facebook''-like autorisation 

   738 \end{itemize}\bigskip

   739 

   740 \item French Revolution and the US Constitution got things ``started'' with 

   741 paper ballots (you first had to bring your own, or later were pre-printed by the parties)

   742 \end{itemize}

   743 \end{frame}}

   744 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   745 

   746 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   747 \mode<presentation>{

   748 \begin{frame}[t]

   749 \frametitle{\begin{tabular}{@ {}c@ {}}Paper Ballots\end{tabular}}

   750 

   751 What can go wrong with paper ballots?

   752 

   753 \only<2>{

   754 \begin{center}

   755 \includegraphics[scale=0.8]{pics/tweet.jpg}\\

   756 \footnotesize William M.~Tweed, US Politician in 1860's\\

   757 ``As long as I count the votes, what are you going to do about it?''

   758 \end{center}}

   759 

   760 \only<3>{

   761 \medskip

   762 \begin{center}

   763 \begin{minipage}{10cm}

   764 {\bf Chain Voting Attack}

   765 \begin{enumerate}

   766 \item you obtain a blank ballot and fill it out as you want

   767 \item you give it to a voter outside the polling station

   768 \item voter receives a new blank ballot

   769 \item voter submits prefilled ballot

   770 \item voter gives blank ballot to you, you give money

   771 \item goto 1

   772 \end{enumerate}

   773 \end{minipage}

   774 \end{center}

   775 }

   776 

   777 \end{frame}}

   778 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   779 

   780 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   781 \mode<presentation>{

   782 \begin{frame}[t]

   783 \frametitle{\begin{tabular}{@ {}c@ {}}Mechanical Voting Machines\end{tabular}}

   784 

   785 \begin{itemize}

   786 \item<1-> Lever Voting Machines (ca.~1930 - 1990)

   787 \only<1>{

   788 \begin{center}

   789 \includegraphics[scale=0.56]{pics/leavermachine.jpg}

   790 \end{center}

   791 }

   792 \item<2->Punch Cards (ca.~1950 - 2000)

   793 \only<2>{

   794 \begin{center}

   795 \includegraphics[scale=0.5]{pics/punchcard1.jpg}\;\;

   796 \includegraphics[scale=0.46]{pics/punchcard2.jpg}

   797 \end{center}

   798 }

   799 \end{itemize}

   800 

   801 \end{frame}}

   802 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   803 

   804 

   805 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   806 \mode<presentation>{

   807 \begin{frame}[c]

   808 

   809 \begin{center}

   810 \includegraphics[scale=0.56]{pics/Voting1.png}

   811 \end{center}

   812 

   813 

   814 \end{frame}}

   815 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   816 

   817 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   818 \mode<presentation>{

   819 \begin{frame}[c]

   820 

   821 \begin{center}

   822 \includegraphics[scale=0.56]{pics/Voting2.png}

   823 \end{center}

   824 

   825 

   826 \end{frame}}

   827 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   828 

   829 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   830 \mode<presentation>{

   831 \begin{frame}[c]

   832 

   833 \begin{center}

   834 \includegraphics[scale=0.56]{pics/Voting3.png}

   835 \end{center}

   836 

   837 

   838 \end{frame}}

   839 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   

   840 

   841 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   842 \mode<presentation>{

   843 \begin{frame}[c]

   844 

   845 \begin{center}

   846 \includegraphics[scale=0.56]{pics/Voting4.png}

   847 \end{center}