\documentclass{article}\usepackage{../style}\begin{document}\section*{Homework 6 (Zero-Knowledge Proofs)}\HEADER\begin{enumerate}\item Explain briefly the purpose of the certification authority inthe public-private key encryption scheme.\item Explain briefly what is meant by a certification authority becoming ``too big to fail'' when it has issued a large number of certificates.\item In which situations does it make sense to install invalid (self-signed) certificates?\item Zero-knowledge protocols depend on three main properties called completeness, soundness and zero-knowledge. Explain what they mean?\item Why do zero-knowledge protocols require an NP-problem as building block?\item Why is it a good choice in a ZKP to flip a coin when requesting a proof from the person who knows the secret?\end{enumerate}\end{document}%%% Local Variables: %%% mode: latex%%% TeX-master: t%%% End: