1. Making the Neutral Traffic Matrix More Meaningful Joseph Choi

2. Given a global passive adversary, want to prevent the adversary from deriving information from observed traffic patterns. Currently, produce a Neutral TM by: (1) Rerouting, (2) Padding, and (3) Delaying Padding acts as a placeholder. – Holds no meaning – Increases traffic load Is there something better?

3. Segmenting Messages Instead of rerouting entire messages, is it reasonable to split them up? – Every exchange within the network will serve a purpose in sender-to-receiver delivery – Non-active nodes aren’t pressured to create artificial traffic and can focus on rerouting Considerations: – Additional processing cost mainly incurred to sender and receiver – Coordinating rerouting of both entire messages and segmented messages

4. Action Plan I.Discovery 1)Neutral TM creation/agreement among parties 2)3 traditional means 3)Existing alternate methods II.Build a new set of tools 1)Come up with new ideas 2)Implementation of new ideas III.Experimentation & Measurement 1)Build neutral, observed TM from actual TM 2)Build set of compatible TMs to observed TM

5. Resources: Richard E. Newman, Ira S. Moskowitz, Paul Syverson and Andrei Serjantov. “Metrics for Traffic Analysis Prevention,” In PET 2003, Dresden, March 2003. R.E. Newman-Wolfe and B.R. Venkatraman. “High Level Prevention of Traffic Analysis,” Seventh Annual Computer Security and Applications Conference, San Antonio, Texas, December 2-6, 1991, pp. 102-109. B.R. Venkatraman and R.E. Wolfe. “Capacity Estimation and Auditability of Network Covert Channels,” 1995 IEEE Computer Society Symp. Security and Privacy, pp. 186-198. X. Fu, B. Graham, Y. Guan, R. Bettati and W. Zhao. “NetCamo: Camouflaging Network Traffic for Real-Time Applications,” Texas Workshop Security of Information Systems, April 2003. Yin Zhang, Matthew Roughan, Carsten Lund, and David Donoho. “An information-theoretic approach to traffic matrix estimation,” 2003 Conference on Applications, Technologies, Architectures, and Protocols for Computer Communications, Karlsruhe, Germany, August 25-29, 2003. Questions?