diff -r d817bb2f80e5 -r ac94033f220a slides09.tex
--- a/slides09.tex	Tue Nov 27 13:41:31 2012 +0000
+++ b/slides09.tex	Tue Nov 27 14:20:38 2012 +0000
@@ -422,7 +422,7 @@
 \item Intuition: whatever is learned from the dataset would be learned regardless of whether
 \bl{$x_i$} participates\bigskip\pause 
 
-\item Noised needed in order to prevent:\\ Christian's salary $=$ 
+\item Noised needed in order to prevent queries:\\ Christian's salary $=$ 
 \begin{center}
 \bl{\large$\Sigma$} all staff $-$  \bl{\large$\Sigma$} all staff $\backslash$ Christian
 \end{center} 
@@ -466,17 +466,50 @@
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \mode<presentation>{
-\begin{frame}[c]
+\begin{frame}[t]
 \frametitle{\begin{tabular}{@{}c@{}}Tor, Anonymous Webbrowsing\end{tabular}}
 
 \begin{itemize}
 \item initially developed by US Navy Labs, but then opened up to the world 
 \item network of proxy nodes
+\item a Tor client establishes a ``random'' path to the destination server (you cannot trace back where the information came from)\bigskip\pause
 \end{itemize}
 
+\only<2>{
+\begin{itemize}
+\item malicious exit node attack: someone set up 5 Tor exit nodes and monitored the traffic:
+\begin{itemize}
+\item a number of logons and passwords used by embassies (Usbekistan `s1e7u0l7c', while
+Tunesia `Tunesia' and India `1234')
+\end{itemize}
+\end{itemize}}
+\only<3>{
+\begin{itemize}
+\item bad apple attack: if you have one insecure application, your IP can be tracked through Tor
+\begin{itemize}
+\item background: 40\% of traffic on Tor is generated by BitTorrent
+\end{itemize}
+\end{itemize}}
+
+
 \end{frame}}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\mode<presentation>{
+\begin{frame}[t]
+\frametitle{\begin{tabular}{@{}c@{}}Take Home Point\end{tabular}}
+
+According to Ross Anderson: \bigskip
+\begin{itemize}
+\item Privacy in a big hospital is just about doable.\medskip
+\item How do you enforce privacy  in something as big as Google
+or complex as Facebook? No body knows.
+\end{itemize}
+
+
+\end{frame}}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%