sen-material: comparison handouts/ho02.tex

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 \noindent Whenever people argue in favour of e-voting they
 seem to be ignoring this basic premise.\bigskip
 \noindent After the debacle of the Florida presidential
-election in 2000, many voting precincts in the US used
+election in 2000, many voting pre\-cincts in the US used
 Direct-Recording Electronic voting machines (DREs) or optical
 scan machines. One popular model of DREs was sold by a
 company called Diebold. In hindsight they were a complete
 disaster: the products were inadequate and the company
 incompetent. Direct recording meant that there was no paper
 the voters had no visible assurance whether the votes were
 correctly cast. Even if there is a printout provided;
 it does not give any guaranty about what is recorded on
 the memory card.
-The machines behind these DREs were ``normal'' windows
+The machines behind these DREs were ``normal'' Windows
 computers, which could be used for anything, for example for
 changing votes. Why did nobody at Diebold think of that? I
 have no idea. But that this was eventually done undetectably
 is the result of the determination of ethical hackers like
 Alex Halderman. His group thoroughly hacked Diebold's DREs
 \caption{Direct-Recording Electronic voting machines above;
 an optical scan machine below.\label{machines}}
 \end{figure}
 What made matters worse was that Diebold tried to hide their
-incompetency and the inferiority of their products, by
+incompetence and the inferiority of their products by
 requiring that election counties must not give the machines up
-for independent review. They also kept their source secret.
+for independent review. They also kept their source code
-This meant Halderman and his group had to obtain a machine not
+secret. This meant Halderman and his group had to obtain a
-through the official channels. They then had to reverse
+machine not through the official channels. They then had to
-engineer the source code in order to design their attack. What
+reverse engineer the source code in order to design their
-this all showed is that a shady security design is no match to
+attack. What all this showed is that a shady security design
-a determined hacker.
+is no match for a determined hacker.
-Apart from the obvious failings (for example no papertrail),
+Apart from the obvious failings (for example no paper trail),
 this story also told another side. While a paper ballot box
 need to be kept secure from the beginning of the election
 (when it needs to be ensured it is empty) until the end of the
 day, electronic voting machines need to be kept secure the
 whole year. The reason is of course that one cannot see
 whether somebody has tampered with the program a computer is
 running. Such a 24/7 security is costly and often even
-impossible, because voting machines need to be distributed
+impossible, because voting machines need to be
-usually the day before the election to the polling stations.
+distributed---usually the day before the election---to the
-These are often schools where the voting machines are kept
+polling stations. These are often schools where the voting
-unsecured overnight. The obvious solution of putting seals on
+machines are kept unsecured overnight. The obvious solution of
-computers did not work: in the process of getting these DREs
+putting seals on computers did not work: in the process of
-discredited (involving court cases) it was shown that seals
+getting these DREs discredited (involving court cases) it was
-can easily be circumvented. The moral of this story is that
+shown that seals can easily be circumvented. The moral of this
-election officials were incentivised with money by the central
+story is that election officials were incentivised with money
-government to obtain new voting equipment and in the process
+by the central government to obtain new voting equipment and
-fell prey to pariahs which sold them a substandard product.
+in the process fell prey to pariahs which sold them a
-Diebold was not the only pariah in this area, but one of the
+substandard product. Diebold was not the only pariah in this
-more notorious ones.
+area, but one of the more notorious ones.
 Optical scan machines are slightly better from a security
 point of view but by no means good enough. Their main idea
 is that the voter fills out a paper ballot, which is then
 scanned by a machine. At the very least the paper ballot can
 \noindent An interesting solution for e-voting was designed in
 India. Essentially they designed a bespoke voting device,
 which could not be used for anything else. Having a bespoke
 device is a good security engineering decision because it
 makes the attack surface much smaller. If you have a
-full-fledged computer behind your system, then you can do
+full-fledged computer behind your voting system, then you can
-everything a computer can do\ldots{}and that is a lot,
+do everything a computer can do\ldots{}and that is a lot,
 including a lot of abuse. What was bad about the devices in
 India was that these machines did not have the important paper
 trail: that means if an election was tampered with, nobody
 would find out. Even if they had by their bespoke design a
 very small attack surface, ethical hackers were still able to
 that even if very good security design decisions are taken,
 e-voting is very hard to get right.\bigskip
 \noindent This brings us to the case of Estonia, which held in
-2007 the worlds first general election that used Internet.
+2007 the worlds first general election that used the Internet.
 Again their solution made some good choices: for example voter
 authentication is done via the Estonian ID card, which
 contains a chip like on credit cards. They also made most of
 their source code public for independent scrutiny. Of course
 this openness means that people (hackers) will look at your
 fingers and find code such as this snippet.
 {\footnotesize\lstinputlisting[language=Python,numbers=none]
 {../progs/estonia.py}}
-\noindent If you want to have a look their code can be
+\noindent If you want to have a look at their code it can be
 downloaded from their github
 repository.\footnote{\url{https://github.com/vvk-ehk/evalimine/}}
 Also their system is designed such that Internet voting is
 used before the election: votes can be changed an unlimited
-amount of times, always the last vote is tabulated, you can
+amount of times; always the last vote is tabulated. You can
 even change your vote on the polling day in person. This is an
 important security mechanism guarding against vote coercion,
 which of course is an important problem if you are allowed to
 vote via Internet.
 \item An auditor can download the entire (shuffled) election
 data and verify the shuffle, decryptions and tally.
 \end{enumerate}
-\noindent As you can see the whole process is not trivial at
+\noindent As you can see, the whole process is not trivial at
 all and leaves out a number of crucial details (such as how to
 best distribute public keys for encryption). It even depends
 on a highly sophisticated process called
 \emph{zero-knowledge-proofs}. They essentially allow one to
 convince somebody else to know a secret without actually
 with your communication partner. We will look at
 zero-knowledge-proofs in a later lecture in more detail.
 The point of these theoretical/hot-air musings is to show that
 such an e-voting procedure is far from convenient: it takes
-much more time to allow, for example, for scrutinising whether
+much more time to allow, for example, scrutinising whether the
-the votes were cast correctly. Very likely it will also not
+votes were cast correctly. Very likely it will also not pass
-pass the benchmark of being understandable to Joe Average.
+the benchmark of being understandable to Joe Average. This was
-This was a standard a court rules that needs to be passed in
+a standard, a high court ruled, that needs to be passed in the
-the German election process.
+German election process.
 The overall conclusion is that an e-voting process involving
 the Internet cannot be made secure with current technology.
 Voting has just too high demands on integrity and ballot
 secrecy. This is different from online banking where the whole

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