Preface

The constant improvement in communication technologies and the related dramatic increase in user demand to be connected anytime and anywhere, to both the wealth of information accessible through the Internet and other users and communities, have boosted the pervasive deployment of wireless and wired networked systems.1 These systems are characterized by the fact of their being large or very large, highly heterogeneous in terms of communication technologies, protocols, and services, and very dynamic, due to continual changes in topology, traffic patterns, and number of active users and services. Intelligent and autonomic management, control, and service provisioning in these complex networks, and in the future networks resulting from their integration and evolution, require the definition of novel protocols and techniques for all the architectural components of the network. In this book we focus on the routing component, which is at the very core of the functioning of every network since it implements the strategies used by network nodes to discover and use paths to forward data/information from sources to destinations. An effective design of the routing protocol can provide the basic support to unleash the intrinsic power of the highly pervasive, heterogeneous, and dynamic complex networks of the next generation. In this perspective, the routing path selection must be realized in a fully automatic and distributed way, and it must be dynamic and adaptive, to take into account the constant evolution of the network state, which is defined by multiple concurrent factors such as topology, traffic flows, available services, etc. The literature in the domain of routing is very extensive. Routing research has fully accompanied the evolution of networking to constantly adapt the routing protocols to the different novel communication technologies and to the changes in user demand. In this book we review routing protocols and algorithms which have been specifically designed taking inspiration from, and reverse engineering the characteristics of, processes observed in nature in general and in insect societies in particular.