Over the past few years, many fundamental changes have occurred in data communications and networking that will shape the future for decades to come. Networking applications such as the Internet and World Wide Web have exploded into the business world. High-speed modems providing megabit data rates (millions of bits per second) over regular telephone lines and cable TV circuits are widely available. New local area network (LAN) and backbone technologies providing gigabit (billions of bits per second) speeds are now available. Metropolitan area network (MAN) and wide area network (WAN) technologies providing terabit (trillions of bits per second) to petabit (quadrillions of bits per second) speeds are on the horizon. The integration of voice and data communication is moving rapidly.
Perhaps the most important change has been the recognition of the strategic importance of communications and networking in both the public and private sector. Today, almost all computers are networked. As we look back on the 1990s, we realize that the importance of the computer was surpassed by the importance of the network.
PURPOSE OF THIS BOOK
Our goal is to combine the fundamental concepts of data communications and networking with practical applications. Although technologies and applications change rapidly, the fundamental concepts evolve much more slowly; they provide the foundation from which new technologies and applications can be understood, evaluated, and compared.
This book has two intended ...