[freehaven-cvs] finish cleaning 7.2

[arma@seul.org (Roger Dingledine)]

Update of /home/freehaven/cvsroot/doc/sync-batching
In directory moria.mit.edu:/home2/arma/work/freehaven/doc/sync-batching

Modified Files:
	sync-batching.tex 
Log Message:
finish cleaning 7.2

paul: i changed some numbers in the robustness graph --
it looked like you had a critical typo under worst case, 16x4 free,
4 crashes?


Index: sync-batching.tex
===================================================================
RCS file: /home/freehaven/cvsroot/doc/sync-batching/sync-batching.tex,v
retrieving revision 1.45
retrieving revision 1.46
diff -u -d -r1.45 -r1.46
--- sync-batching.tex	26 Jan 2004 15:39:40 -0000	1.45
+++ sync-batching.tex	26 Jan 2004 15:58:36 -0000	1.46
@@ -739,7 +739,7 @@
 
 \subsection{Robustness of Message Delivery}
 
-Better anonymity is achieved by longer routes. For example, if we
+Better security can be achieved by longer routes. For example, if we
 formed our 16 nodes into a 1x16
 cascade or a 16x16 free-route, there is almost no falloff in entropy
 until each node has a ninety
@@ -752,13 +752,13 @@
 it at some point). Such a network is very brittle. For the 1x16 cascade, it
 is even worse: a single node crash blocks all message delivery.
 (We might take advantage of schemes to bypass a single failed node
-\cite{pfitzmann85}, but this does not address the real problems.)
+\cite{pfitzmann85}, but it's not clear how this works with the synchronous
+approach.)
 Parallel cascades can be added to the network, but unlike the
-free-route, this will \emph{a priori} reduce the entropy of an input
-message for the same size mixnet batch. Thus robustness can be an
+free-route, they will \emph{a priori} reduce the entropy of an input
+message for a given size mixnet batch. Robustness is an
 important question.
 
-
 \begin{table} \caption{Percent of messages delivered}
 \label{table:expected-delivery}
 \renewcommand{\arraystretch}{1.3}
@@ -769,10 +769,10 @@
  & Topology & \ 1 crash \   & \ 2 crash \ & \ 3 crash \  & \ 4 crash \ \\
 \hline
 
-                         & 16x16 free    & 36   & 12   & 04   & 1       \\
-Worst possible           & 4x4 cascade \ & 75   & 50   & 25   & 0       \\
-adversary distribution \ & 4x4 stratif.  & 75   & 50   & 25   & 0       \\
-                         & 16x4 free     & 77   & 59   & 44   & 3       \\
+                         & 16x16 free    & 36   & 12   & 04   & 01      \\
+Worst possible           & 4x4 cascade \ & 75   & 50   & 25   & 00      \\
+adversary distribution \ & 4x4 stratif.  & 75   & 50   & 25   & 00      \\
+                         & 16x4 free     & 77   & 59   & 44   & 32      \\
 \hline
 \hline
                          & 16x16 free    & 36   & 12  & 04   & 01      \\
@@ -795,8 +795,8 @@
 
 Table~\ref{table:expected-delivery} shows that
 4x4 cascades and 4x4 stratified networks do roughly the same on
-average, but for very different reasons. Probability that
-configurations will block all messages increases much more quickly for
+average, but this is for very different reasons. The chance that the
+configuration will block all messages increases much more quickly for
 cascades, but the maximum possible delivery of messages remains much
 higher. This can be seen in the table reflecting the most favorable
 adversary distribution for up to four node crashes. To further
@@ -810,13 +810,12 @@
 distributions.
 
 Of the scenarios we have considered, a 16x4 free route has the best
-expected chance of message delivery for random distributions of the
-adversary. It outperforms the others unless the adversary has a
+expected chance of message delivery for random adversary distribution.
+It outperforms the others unless the adversary has a
 particularly innocuous distribution, in which case cascades do better.
 Also note that the expected fraction of passed messages is the same
-for free routes regardless of which four nodes fail. In this sense
-it is the most robust wrt adversary distribution not just the adversary
-size.
+for free routes regardless of which nodes fail: it is the most robust
+with respect to adversary distribution as well as adversary size.
 
 \subsection{Robustness of Anonymity}
 \label{subsec:anonymity-robustness}

***********************************************************************
To unsubscribe, send an e-mail to majordomo@seul.org with
unsubscribe freehaven-cvs       in the body. http://freehaven.net/