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%========================================================================
\begin{center}
\textbf{\Large{Homework 6}} \vspace{2mm}

Mathematics in Computer Science
%John E. Hopcroft
\end{center}
\vspace{1mm}

\begin{enumerate}
\item Given an encoding algorithm $E$ and a decoding algorithm $D$
such that $E(D(m))=m$ and $D(E(m))=m$ how would you set up a public
key cryptosystem?
  \begin{enumerate}
  \item What is made public?
  \item How is a message sent?  You do not need to explain
  padding or any sophisticated aspect, just a one sentence
  explaining the basic method.
  \item How does one sign an encriptic message?
  \end{enumerate}
  \item Give a brief description of how to attach a signature to a
message in a public key crypto system. Two or three lines are
sufficient for your answer.
\newline\newline
  \end{enumerate}
%========================================================================
\end{document}
