This is an elementary textbook on an advanced topic: broadband telecommunica­ tion networks. I must declare at the outset that this book is not primarily intended for an audience of telecommunication specialists who are weIl versed in the concepts, system architectures, and underlying technologies of high-speed, multi­ media, bandwidth-on-demand, packet-switching networks, although the techni­ caIly sophisticated telecommunication practitioner may wish to use it as a refer­ ence. Nor is this book intended to be an advanced textbook on the subject of broadband networks. Rather, this book is primarily intended for those eager to leam more about this exciting fron tier in the field of telecommunications, an audience that includes systems designers, hardware and software engineers, en­ gineering students, R&D managers, and market planners who seek an understand­ ing of local-, metropolitan-, and wide-area broadband networks for integrating voice, data, image, and video. Its primary audience also includes researchers and engineers from other disciplines or other branches of telecommunications who anticipate a future involvement in, or who would simply like to leam more about, the field of broadband networks, along with scientific researchers and corporate telecommunication and data communication managers whose increasingly sophis­ ticated applications would benefit from (and drive the need for) broadband net­ works. Advanced topics are certainly not ignored (in fact, a plausible argument could be mounted that aIl of the material is advanced, given the infancy of the topic).