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@@ -160,7 +160,7 @@ or flooding and send less data until the congestion subsides.
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\textbf{Directory servers:} The earlier Onion Routing design
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planned to flood link-state information through the network---an approach
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-that can be unreliable and open to partitioning attacks.
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+that can be unreliable and complex. % open to partitioning attacks.
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Tor takes a simplified view toward distributing such
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information. Certain more trusted nodes act as \emph{directory
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servers}: they provide signed directories that describe known
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@@ -703,8 +703,8 @@ occurred, and the cell is discarded.)
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OPs treat incoming relay cells similarly: they iteratively unwrap the
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relay header and payload with the session keys shared with each
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-OR on the circuit, from the closest to farthest. (Because we use a
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-stream cipher, encryption operations may be inverted in any order.)
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+OR on the circuit, from the closest to farthest. % (Because we use a
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+%stream cipher, encryption operations may be inverted in any order.)
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If at any stage the OP recognizes the streamID, the cell must have
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originated at the OR whose encryption has just been removed.
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@@ -842,7 +842,7 @@ first four bytes of the current digest. Each also keeps a SHA-1
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digest of data received, to verify that the received hashes are correct.
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To be sure of removing or modifying a cell, the attacker must be able
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-to either deduce the current digest state (which depends on all
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+to deduce the current digest state (which depends on all
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traffic between Alice and Bob, starting with their negotiated key).
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Attacks on SHA-1 where the adversary can incrementally add to a hash
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to produce a new valid hash don't work, because all hashes are
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@@ -1188,7 +1188,7 @@ must build circuits and use them to anonymously test router reliability
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Using directory servers is simpler and more flexible than flooding.
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Flooding is expensive, and complicates the analysis when we
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start experimenting with non-clique network topologies. Signed
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-directories are less expensive, because they can be cached by other
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+directories can be cached by other
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onion routers.
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Thus directory servers are not a performance
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bottleneck when we have many users, and do not aid traffic analysis by
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@@ -1656,7 +1656,7 @@ confirmation will immediately and automatically defeat a low-latency
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anonymity system. Even high-latency anonymity systems can be
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vulnerable to end-to-end traffic confirmation, if the traffic volumes
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are high enough, and if users' habits are sufficiently distinct
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-\cite{limits-open,statistical-disclosure}. Can anything be done to
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+\cite{statistical-disclosure,limits-open}. Can anything be done to
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make low-latency systems resist these attacks as well as high-latency
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systems? Tor already makes some effort to conceal the starts and ends of
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streams by wrapping long-range control commands in identical-looking
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