| Advances in wireless communications and computing technologies have lent great forces to mitigating physical restrictions on accessing the Internet and web-based services, providing us with flexibility, convenience, increased efficiency and improved life quality. It is observed that privacy and security breaches have already penetrated every aspect of our activities and living environment including healthcare, financial, voting, e-commerce, military, etc, especially when these activities take place wirelessly. Thus, there is an urgent need for the development of architectures assuring privacy and security that are imperative to safeguarding confidential information wherever it digitally resides. Despite the paramount importance, little progress has been introduced by researchers in the design of security and privacy architectures for wireless networks and critical systems. In this dissertation, we strive to solve several issues around user anonymity and privacy by carrying out security solutions.;We first propose a security architecture that ensures user anonymity and traceability in wireless mesh networks. We then investigate an ID-based security system for vehicular ad hoc networks to guarantee user privacy, non-frameability of honest users, and traceability of misbehaving users. Next, we devise a heterogeneous authentication framework to assure user anonymity during network access for vehicular mesh networks. Moreover, we consider patients' electronic health record (EHR) privacy by first designing a secure EHR system for health information sharing, and then proposing a security scheme to simultaneously achieve patient privacy and secure emergency response. Finally, we present a privacy-preserving scheme for online social networks to provide efficient revocation, efficient search over encrypted data files, and dynamic change of group membership. |
