A comprehensive guide to tomorrow's world of ubiquitous computing where users can access and manipulate information from everywhere at all times. The emphasis is on networking, systems and standards rather than detailed physical implementation. Addressed are many technical obstacles, such as, connectivity, levels of service, performance, and reliability and fairness. The authors also describe the existing enabling off-the-shelf technologies and its underlying infrastructure known as pervasive networking (PervNet). PervNet ties different sets of smart nodes together enabling them to communicate with each other to provide pervasive computing services to users. Throughout the book, important issues related to scalability, transparency, security, energy management, QoS provisioning, fault tolerance and disconnected operations are discussed. This work provides a research and development perspective to the field of PervNet and should serve as a reference for network designers, operators and developers.