hws/hw07.tex
author Christian Urban <christian dot urban at kcl dot ac dot uk>
Mon, 25 Nov 2013 20:31:01 +0000
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\documentclass{article}
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\usepackage{charter}
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\usepackage{hyperref}
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\usepackage{amssymb}
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\usepackage{proof}
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\begin{document}
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\section*{Homework 7}
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\begin{enumerate}
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\item Suppose a judgement is of the form:
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\begin{center}
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$Alice\;\textit{says}\;S \wedge Bob\;\textit{says}\;S \vdash Bob\;\textit{says}\;S \wedge Alice\;\textit{says}\;S$
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\end{center}
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Assume you want to use the inference rule
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\begin{center}
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\mbox{\infer{\Gamma \vdash F_1 \wedge F_2}{\Gamma \vdash F_1 & \Gamma \vdash F_2}}
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\end{center}
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for constructing a proof of the judgement. What do the premises look like? 
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%\item The informal meaning of the formula \mbox{$P\;\mapsto\;Q$} is `$P$ speaks for
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%$Q$'. Give a definition for this formula in terms of $\textit{says}$.
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%\item In Unix, what should be the general architecture of a network application that 
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%processes potentially hostile data from the Internet? (Hint: Focus on the fact that in Unix
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%you can give different privileges to processes.)
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%\item Explain what are the differences between dictionary and brute forcing attacks  against  passwords.
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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: