--- a/hws/hw04.tex	Wed Oct 09 15:52:17 2013 +0100
+++ b/hws/hw04.tex	Mon Oct 21 23:28:03 2013 +0100
@@ -8,33 +8,9 @@
 \section*{Homework 4}
 
 \begin{enumerate}
-\item Voice voting is the method of casting a vote in the `open air' for everyone
-present to hear. Which of the following security requirements do paper ballots 
-satisfy better than voice voting? Check all that apply and give a brief explanation 
-for your decision.
-
-\begin{itemize}
-\item[$\Box$] Integrity\bigskip\bigskip
-\item[$\Box$] Enfranchisement\bigskip\bigskip
-\item[$\Box$] Ballot secrecy\bigskip\bigskip
-\item[$\Box$] Voter authentication\bigskip\bigskip
-\item[$\Box$] Availability\bigskip\bigskip
-\end{itemize}
+\item Explain what is meant by \emph{Kerckhoffs' principle}.
 
 
-\item Explain how an attacker can use chain voting in order to influence the outcome of a 
-poll using paper ballots. 
-
-\item Which of the following mechanisms help with defending against chain voting? Check all 
-that apply. Give a brief reason for each defence that mitigates chain voting attacks.
-
-\begin{itemize}
-\item[$\Box$] Using a glass ballot box to make it clear there are no ballots in the box before the start of the election.
-\item[$\Box$] Distributing ballots publicly before the election.
-\item[$\Box$] Checking that a voter's ID (drivers license, passport) matches the voter.
-\item[$\Box$] Each ballot has a unique ID. When a voter is given a ballot, the ID is recorded. When the voter submits his or her ballot, this ID is checked against the record.
-\end{itemize}
-
 \end{enumerate}