ate function within the company, but now it is an essential element of telecom service. (See Chapter 9.) What This Book Covers The rapid progress in embedded devices, intelligent wearables, virtual reality, robot- ics, grid computing, and real-time communications is ushering in a new era of appli- cations-applications that require enormous bandwidth, low latencies, minimal loss, guaranteed performance, wireless broadband, and converged infrastructures. This book provides a thorough foundation for understanding a wide range telecommunications principles and technologies. It provides a concentrated, high- level overview of the terminology and issues that comprise telecommunications, and it discusses the major telecommunications infrastructures, including the PSTN, the Internet, cable TV, and wireless. It also examines the latest perspectives and developments governing next-generation networks, including next-generation architectures, infrastructures, IP telephony, VPNs, broadband access alternatives, and broadband wireless applications. Even though the ICT industry has gone through some hard times lately, logic dictates that we can only look forward to greater emphasis on the use of ICT. The book is divided into four parts: Part I, "Communications Fundamentals," discusses the basics, the arts and sciences of telecommunications. It begins by explaining the factors contrib- uting to the telecommunications revolution and talks about some of the exciting new technologies on the horizon. Part I gives you a good ground- ing in the basics of telecommunications technology and terminology, cover- ing communications fundamentals and including the characteristics and uses of the various transmission media. Part I also discusses the processes involved in establishing communications channels, examines the differ- ences between circuit-switched and packet-switched networks, and explores the nature of the traditional PSTN. Part II, "Data Networking and the Internet," introduces the basics of data communications and networking. It