hws/hw01.tex
author Christian Urban <christian dot urban at kcl dot ac dot uk>
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\documentclass{article}
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\usepackage{../style}
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\begin{document}
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\section*{Homework 1}
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\begin{enumerate}
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\item {\bf (Optional)} If you want to have a look at the code
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  presented in the lectures, install \texttt{Node.js} available (for free) from
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\begin{center}
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\url{http://nodejs.org}
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\end{center}
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It needs aslo the Node-packages Express, Cookie-Parser, Body-Parser and 
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Crypto. They can be easily installed using the Node package manager \texttt{npm}.
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\item Practice thinking like an attacker. Assume the following situation:
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  \begin{quote}\it
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    Prof.~V.~Nasty gives the following final exam question (closed books, closed notes):\bigskip
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    \noindent
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    \begin{tabular}{@ {}l}
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      Write the first 100 digits of pi:\\
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      3.\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
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    \end{tabular}
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  \end{quote}
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\noindent
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Think of ways how you can cheat in this exam? How would you defend
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against such cheats.
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\item Here is another puzzle where you can practice thinking like an
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  attacker: Consider modern car keys. They wirelessly open and close
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  the central locking system of the car. Whenever you lock the car,
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  the car ``responds'' by flashing the indicator lights. Can you think
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  of a security relevant purpose for that? (Hint: Imagine you are in
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  the business of stealing cars. What attack would be easier to
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  perform if the lights do not flash?)
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\item Imagine you are at your home a broadband contract with
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      TalkTalk. You do not like their service and want to
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      switch, say, to ???. The procedure between the Internet
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      providers is that you contact ??? and set up a new
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      contract and they will automatically inform TalkTalk to
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      terminate the old contract. TalkTalk will then send you
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      a letter to confirm that you want to terminate. If they
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      do not hear from you otherwise, they will terminate the
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      contract and will request any outstanding cancellation
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      fees. Can you imagine in which situations this way of
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      doing things can cause you a lot of headaches? For this
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      consider that TalkTalk needs approximately 14 days to
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      reconnect you.
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\item A water company has a device that transmits the meter
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      reading when their company car drives by. How can this 
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      transmitted data be abused, if not properly encrypted?      
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      If you identified an abuse, then how would you 
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      encrypt the data so that such an abuse is prevented.
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%\item Imagine there was recently a break in where computer criminals
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%  stole a large password database containing 
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\item Explain what hashes and salts are. Describe how they can be used
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  for ensuring data integrity and storing password information.
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\item What is the difference between a brute force attack and a 
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  dictionary attack on passwords? 
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\item What are good uses of cookies (that is browser cookies)?
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\item Why is making bank customers liable for financial fraud a bad
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design choice for credit card payments?
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\end{enumerate}
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\end{document}
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%%% Local Variables: 
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%%% mode: latex
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%%% TeX-master: t
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%%% End: