Toward an Analytical Approach to Anonymous Wireless Networking

Transmissions in a wireless network are susceptible to unauthorized traffic analysis by eavesdroppers. Although cryptography can protect the contents of communication, the transmission times of packets alone can provide significant networking information. This article focuses on analytical approaches to anonymous networking for the prevention of timing based traffic analysis. In particular, we propose an analytical measure for anonymity, and develop provably anonymous countermeasures for wireless ad hoc and sensor networks, where traffic is subjected to tight constraints on medium access and latency. A key objective is to bridge a long standing gap between the information theoretic approach to secrecy in communication and a more pragmatic approach of Chaum Mixing used for anonymity in Internet applications. The efficacy of the proposed approach is demonstrated using an orthogonal transmitter directed signaling network. Keywords — Traffic analysis, Anonymity, Mixing, Equivocation, Rate-Distortion. I