Networked systems are central to many activities in modern societies and wireless networking has been expanding fast the reach of information. However, these increasingly many novel computing tools are a double-edged sword: Without appropriate defense mechanisms, the manipulation of networked systems can make antisocial and criminal behavior easy. This can jeopardize the benefits of new technologies or even deter their deployment. With numerous threats and motivated and able adversaries, it is paramount to integrate mechanisms that manage adversarial behavior.

In this talk, I will discuss how to secure wireless networked systems; which not only proliferate but also pose new challenges. I will start with the problem of securing neighbor discovery, which is fundamental to wireless networking. I will show the need of novel verification approaches, through an impossibility result and the development of practical, proven secure protocols. Then, I will discuss how to secure communication across self-organized, open networking infrastructures; in particular, secure and fault-tolerant communication in mobile ad hoc networks. I will also present elements of a security architecture for vehicular communication systems. In such a complex networked system, I will consider security designs in the light of stringent performance requirements and system constraints. Finally, if time permits, I will briefly survey other research interests and activities.