The first edition of this book covered in depth the mathematical theory of nblocking multistage interconnecting networks, which is applicable to both communication and computer networks. This comprehensively updated version puts more emphasis to the multicast and multirate networks which are under fast development recently due to their wide applications. This comprehensively updated new edition t only introduces the classical theory of the fundamental point-to-point network but also has a renewed emphasis on the latest multicast and multirate networks. The book can serve as either a one- or two-semester textbook for graduate students of information science, (electronic) communications, and applied mathematics. In addition, as all the relevant literature is organized and evaluated under one structured framework, the volume is an essential reference for researchers in those areas.