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@@ -94,7 +94,7 @@ forcing successive nodes in the circuit to decrypt it. Rather than using
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onions to lay the circuits, Tor uses an incremental or \emph{telescoping}
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path-building design, where the initiator negotiates session keys with
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each successive hop in the circuit. Onion replay detection is no longer
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-necessary, and the network as a whole is more reliable to boot, since
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+necessary, and the process of building circuits is more reliable, since
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the initiator knows which hop failed and can try extending to a new node.
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\item \textbf{Applications talk to the onion proxy via Socks:}
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@@ -343,12 +343,12 @@ cebolla (?)\\
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Like other low-latency anonymity designs, Tor seeks to frustrate
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attackers from linking communication partners, or from linking
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multiple communications to or from a single point. Within this
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-overriding goal, however, several design considerations have directed
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+main goal, however, several design considerations have directed
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Tor's evolution.
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First, we have tried to build a {\bf deployable} system. [XXX why?]
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This requirement precludes designs that are expensive to run (for
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-example, by requiring more bandwidth than volunteers are easy to
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+example, by requiring more bandwidth than volunteers will easily
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provide); designs that place a heavy liability burden on operators
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(for example, by allowing attackers to implicate operators in illegal
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activities); and designs that are difficult or expensive to implement
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@@ -406,9 +406,10 @@ sending or receiving communications via Tor.
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\SubSection{Adversary Model}
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\label{subsec:adversary-model}
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-Like all practical low-latency systems, Tor is broken against a global
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-passive adversary, the most commonly assumed adversary for analysis of
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-theoretical anonymous communication designs. The adversary we assume
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+Like all practical low-latency systems, Tor is not secure against a
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+global passive adversary, which is the most commonly assumed adversary
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+for analysis of theoretical anonymous communication designs. The adversary
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+we assume
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is weaker than global with respect to distribution, but it is not
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merely passive.
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We assume a threat model that expands on that from \cite{or-pet00}.
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@@ -424,8 +425,8 @@ The basic adversary components we consider are:
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link. Can change all those things that an observer can observe up to
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the limits of computational ability (e.g., cannot forge signatures
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unless a key is compromised).
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-\item[Hostile initiator:] can initiate (destroy) connections with
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- specific routes as well as varying the timing and content of traffic
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+\item[Hostile initiator:] can initiate (or destroy) connections with
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+ specific routes as well as vary the timing and content of traffic
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on the connections it creates. A special case of the disrupter with
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additional abilities appropriate to its role in forming connections.
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\item[Hostile responder:] can vary the traffic on the connections made
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@@ -434,6 +435,10 @@ The basic adversary components we consider are:
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special case of the disrupter.
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\item[Key breaker:] can break the longterm private decryption key of a
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Tor-node.
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+% Er, there are no long-term private decryption keys. They have
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+% long-term private signing keys, and medium-term onion (decryption)
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+% keys. Plus short-term link keys. Should we lump them together or
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+% separate them out? -RD
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\item[Compromised Tor-node:] can arbitrarily manipulate the connections
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under its control, as well as creating new connections (that pass
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through itself).
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@@ -545,7 +550,7 @@ in an offline clique.
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Rendezvous points are a building block for \emph{location-hidden services}
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(aka responder anonymity) in the Tor network. Location-hidden
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-services means Bob can offer a tcp service, such as an Apache webserver,
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+services means Bob can offer a tcp service, such as a webserver,
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without revealing the IP of that service.
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We provide this censorship resistance for Bob by allowing him to
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@@ -739,6 +744,9 @@ them.
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\item \emph{Selectively DoS servers.}
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\item \emph{Introduce timing into messages.}
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\item \emph{Tagging attacks.}
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+the exit node can change the content you're getting to try to
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+trick you. similarly, when it rejects you due to exit policy,
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+it could give you a bad IP that sends you somewhere else.
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\end{itemize}
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\item \textbf{Directory attacks}
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