Excerpts

The prior editions of this book were more successful than I had originally hoped. The third edition of this book has been adopted at universities around the world. But this industry changes quickly, and with the many advances in data communications, a fourth edition was required to update certain topics and add new ones as networks become a part of everything we do. The goals of the fourth edition remain the same as those of the first three. After years of teaching data communications classes, I was still not satisfied with the scope, clarity, and readability of other available textbooks. Some textbooks were aimed at advanced electrical engineering students, while others covered only the business aspects of data communications. I sought to create a text that would be accessible to the novice and at the same time challenging to the engineer or technical professional. Those readers who desire a broad overview can simply follow the body of this text, while more advanced readers can examine concepts in detail inside the special shaded boxes. Simply stated, I have tried to demystify data communications. I draw on practical examples to explain all technical concepts, as I have found this technique very successful in my teaching experience. This text introduces the language of data communications. It provides a practical understanding of all the relevant terminology, concepts, hardware, software, protocols, architectures, and other information necessary to make the reader literate in data communications. Current and future product offerings are discussed. After finishing the book, the reader should be able to make intelligent decisions on the appropriate design, purchase, integration, and use of data communications equipment and systems. The text begins with a thorough introduction to telecommunications, an understanding of which is essential in order to appreciate data communications hardware and software designs. The book then progresses logically from the basic concepts of data communications to transmission and interface standards and then to data integrity and security. At that point, it is appropriate to discuss architectures and protocols in order to tie the components together, which leads to a thorough presentation of different networks. The text concludes with a discussion of the convergence of voice and data communications and an in-depth examination of standards currently being developed. At the end of each chapter, I have provided a summary, as well as a list of newly introduced terms. Exercises are also included to help the reader review the material. A thorough glossary of more than 1,350 terms and acronyms, an improved index, and a topical bibliography will ensure this book's usefulness to the reader as a reference tool long after any courses are completed. The impact of continuously evolving technologies in this vital industry must not be overlooked. I have therefore focused on both fundamental concepts and practical applications so that the reader can understand data communications today and also be prepared to understand future advances in technology, products, and standards. The key in developing such a text is not only what to include, but also what to leave out. Many thicker books on data communications are available. Unlike these other texts, this book boils it down to the essentials. I believe that I have succeeded in providing a clear, well-balanced, and practical approach to data communications. WHAT'S NEW IN THE FOURTH EDITION The entire book has been revised with the increasing importance of the Internet and client/server computing in mind. For example, the fourth edition does the following: Provides enhanced coverage of the Internet, search engines, Web servers, load balancing, Web storage, chat, instant messaging, browsing, Web backup, streaming media, and access technologies Describes the latest corporate and home LAN environments, including Fast Ethernet, Gigabit Ethernet, and 10-Gigabit Ethernet Covers the latest IEEE 802.11 a/b/g Wi-Fi wireless LAN standards and hot spots Includes expanded coverage of protocols: TCP/IP, SMTP, MIME, HTTP, Telnet, FTP, UDP, SNMP, SLIP, PPP, ARP, ICMP, DNS, DHCP, MPLS, POP3, IMAP4, Mobile IP, SSL, IPSec, PPTP, SIP, and many others Offers an in-depth security discussion of network threats, defense mechanisms, and encryption technology Explains changes in the telecommunications industry and Voice Over IP Describes the latest high-speed interface and transmission technologies Provides enhanced coverage of cellular 1G/2G/2.5G/3G technologies The following organizational changes have been made since the third edition: Data interfaces and transmission have now been split into two chapters. The chapter on improving data communications efficiency has been removed. The discussion of multiplexers is now found in the data transmission chapter, while the discussion of front ends and related legacy equipment has been moved to Appendix B for those who are interested. The chapter on architectures and protocols now focuses almost entirely on open, standard approaches. Proprietary protocols are mentioned briefly as examples only where appropriate, and SNA coverage has been moved to Appendix C for those who are interested. The last chapter has been broadened to cover the convergence of voice and data communications, and it includes comparisons of the different technologies, as well as a section on future prospects. Finally, definitions of more than 250 new terms and acronyms within the new material have been added to the glossary. A companion website for students, as well as a dedicated instructor's website with numerous instructional resources, can be found at http://www.prenhall.com/beyda . Excerpted from Data Communications: From Basics to Broadband by William J. Beyda All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.