As society continues to depend on the rapidly expanding wireless ecosystem, we are challenged with serious threats related to user privacy, data confidentiality, and critical system availability. A significant portion of these threats is attributed to the broadcast nature of wireless transmissions. Using commodity radio hardware, unauthorized parties can easily eavesdrop on over-the-air transmissions and breach the privacy of communicating users by tracking their whereabouts and movements, and inferring their associations, health state, and preferences. Common (application-level) cryptographic mechanisms fail to provide adequate security and privacy, as they leave low-level transmission identifiers open to traffic analysis. This project focuses on designing and evaluating privacy-preserving communication methods for mitigating information leakage due to eavesdropping. Novel physical-layer obfuscation techniques that carefully control intentional interference from transmitters and/or receivers are being designed to prevent traffic analysis at the frame level. The goal of these techniques is to render packets (including their unencrypted headers) undecodable by any unauthorized party. These physical-layer techniques are augmented with traffic normalization mechanisms at the flow level, whose objective is to hide complex network and traffic features, such as device role, routing paths, etc. Colluding eavesdroppers who monitor the system for long periods of time are also being investigated. The outcomes of this project are expected to have profound impacts on the security, privacy, and usability of a wide range of critical systems that rely on wireless technologies, including transportation and aviation networks, mobile computing platforms, e-commerce, critical national infrastructures, medical systems, and others.
TWC: Medium: Leakage of Communications Signatures: Analysis of Eavesdropping Attacks and Proactive Countermeasures