hws/hw06.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 6 (Zero-Knowledge Proofs)}
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\HEADER
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\begin{enumerate}
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\item Explain briefly the purpose of the certification authority in
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the public-private key encryption scheme.
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\item Explain briefly what is meant by a certification authority
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  becoming ``too big to fail'' when it has issued a large number 
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  of certificates.
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\item In which situations does it make sense to install
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      invalid (self-signed) certificates?
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\item Zero-knowledge protocols depend on three main properties called
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  completeness, soundness and zero-knowledge.  Explain what they mean?
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\item Why do zero-knowledge protocols require an NP-problem as building
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  block?
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\item Why is it a good choice in a ZKP to flip a coin when requesting a 
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  proof from the person who knows the secret?
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\item \POSTSCRIPT
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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: