Embedding network capabilities in a plethora of new devices and infrastructures--the Internet-of-Things, vehicular and aviation networks, the critical national infrastructure, industrial plants--are dramatically transforming the modern way of living. The rapid deployment pace of these emerging applications has brought unprecedented security challenges related to data confidentiality, user privacy, and critical infrastructure availability. A significant portion of these threats is attributed to the broadcast nature of the wireless medium, which exposes systems to easy-to-launch passive and active attacks. The slow security standards rollout combined with the ever-shrinking time-to-market, the device heterogeneity and the lack of user-friendly input interfaces (screen, keyboard, etc.) only exacerbate the security challenges.
In this dissertation, we address the fundamental problem of trust establishment in the context of emerging network applications. We present techniques integrating physical layer properties with cryptographic primitives to guarantee message integrity and bootstrap initial trust without relying on any prior secrets. We present the ``helper'' security paradigm in which security is outsourced to one or more dedicated devices to allow for the scalable pairing of off-the-shelf heterogeneous devices. In addition, we present our work on message integrity verification of navigation information for aircrafts (speed, location, and heading) by exploiting the Doppler spread of the wireless channel. Finally, we develop a secure and fast voting technique for distributed networks which allows fast coordination of a group of devices without the overhead of messaging
