PrefaceWe have entered the era of wireless networks. By now, the number of wireless phones has superseded that of wired ones. Wireless LANs are routinely used by millions of nomadic users. Wireless devices have become commonplace in private homes, factories, and hospitals. And technologists promise us a world of ubiquitous computing, in which myriads of tiny, untethered sensors and actuators will communicate with each other, promptly taking care of our various needs and wishes.In addition to this pervasiveness, we are witnessing a change of paradigm: initially, wireless devices had limited or no programmability and were managed (and secured) in a highly centralized fashion. Today, high-tier wireless end-systems are full-fledged personal computers and take an increasingly active role in the networking mechanisms. In the extreme case of multi-hop ad hoc networks, the end systems are the network.Unfortunately, this evolution is creating new vulnerabilities. Even existing wireless networks (and especially wireless LANs) exhibit a number of security weaknesses, some of which have been painstakingly fixed a posteriori. It is now clear that the security solutions devised for wired networks cannot be used as such to protect the wireless ones. An additional problem is that the frenzy to commercialize quickly new products and new services is in contradiction with the design of a well-thought (and possibly standardized) secure architecture.This textbook aims at preventing ubiquitous computing from becoming a pervasive nightmare. It contains a thorough description of existing and envisioned mechanisms devised to thwart misdeeds against wireless networks. Indeed, we believe that the protection of wireless networks now requires more attention and a more systematic a priori approach.In addition to the usual security concerns of networking, we need to address selfish behavior. The reason is that each wireless communication makes use of a fraction of the spectrum that has been and will remain a scarce resource. Moreover, most wireless devices are battery-powered, and for them energy is scarce as well. Consequently, the behavior of a wireless device can affect the service enjoyed by a another, neighboring iv device. Likewise, the behavior of a wireless network can affect the performance of another wireless network, especially if both networks operate in the same frequency band. These are the reasons we mention "cooperation" in the title of this book; wherever appropriate, we will make use of game theory in order to formalize the problems.We believe this textbook to be the first of its kind regarding the treatment of security and cooperation in wireless networks. Due to the constant evolution of the field, one of the major challenges of writing such a book is ensuring that it will have a reasonably long shelf life (and that the material learned from this book has long lasting value). The strategy we have adopted is to focus on the principles and to keep examples as generic as possible.
What this book is notThis book covers a subst...