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Center for Nonlinear Studies |
Encrypted protocols, such as SSL, are becoming more prevalent because of the growing use of e-commerce, anonymity services, and secure authentication. Likewise, traffic analysis is becoming more common because it is often the only way to analyze these protocols. Though there are many valid uses for traffic analysis (such as network policy enforcement and intrusion detection), it can also be used to maliciously compromise the secrecy or privacy of a user. While the payload can be strongly protected by encryption, analysis of traffic patterns can yield information about the type and nature of traffic. We are exploring the use of synthetically generated "cover traffic" in which real traffic is embedded. Perfect preservation of privacy is achieved if the cover traffic behavior is completely independent of real traffic, and yet a high price in average increased delay is experienced. Tradeoffs exist between privacy (measured in terms of entropy of probability distributions of real traffic behavior) and performance (measured in terms of average latency). This talk describes the problem and presents algorithms we've developed for managing this tradeoff.
Host: Guanhua Yan