TWC: Medium: Leakage of Communications Signatures: Analysis of Eavesdropping Attacks and Proactive Countermeasures

随着社会继续依赖于快速扩展的无线生态系统，我们面临着与用户隐私、数据机密性和关键系统可用性相关的严重威胁。这些威胁的很大一部分归因于无线传输的广播性质。使用商品无线电硬件，未经授权的一方可以很容易地窃听空中传输，并通过跟踪他们的行踪和移动，推断他们的关联，健康状态和偏好来侵犯通信用户的隐私。常见的（应用程序级）加密机制无法提供足够的安全性和隐私，因为它们将低级别的传输标识符开放给流量分析。该项目的重点是设计和评估隐私保护通信方法，以减少由于窃听而导致的信息泄漏。新的物理层混淆技术，仔细控制故意干扰发射机和/或接收机正在设计，以防止在帧级的流量分析。这些技术的目标是使数据包（包括其未加密的报头）无法被任何未授权方解码。这些物理层技术增加了流量规范化机制，在流的水平，其目的是隐藏复杂的网络和流量功能，如设备的角色，路由路径等串通窃听谁监视系统的时间也正在调查。该项目的成果预计将对依赖无线技术的各种关键系统的安全性、隐私性和可用性产生深远影响，这些系统包括交通和航空网络、移动的计算平台、电子商务、关键国家基础设施、医疗系统等。

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.