ivering telecommunications education in all con- Acknowledgments xxvii texts-academic, professional, government, financial, consulting, education, enter- tainment, and health care. I couldn't have hoped for a better set of reviewers! In addition, my sincere and heartfelt thanks go to all those behind the scenes at Addison-Wesley. From the editors and production staff to the marketing team and artists: You've all been an absolute pleasure to work with again on this second edition of Telecommunications Essentials! In particular, I'd like to thank Chrysta Meadowbrooke, our copyeditor; both Kitty and I are extremely impressed with her thoroughness and commitment, and she definitely made a difference in ensur- ing that there were no loose ends! I would also like to thank Alan Clements, the designer for the book cover. He made sure my vision came to life, and as a result, we have a cover that is exciting visually and conveys all the key concepts the book represents. Thanks to Julie Nahil, Kim Arney, and all the rest of the talented people who worked on this project. Aside from those intimately involved with the production of this second edi- tion, there are my faithful colleagues and friends whose support and informal con- tributions were also of tremendous value to me. You all know who you are, and you know I thank you from the bottom of my heart for your continued support and inspiration. It is my grand fortune to have SO many treasured friends and col- leagues that I am not able to name you all without making a chapter out of it! Finally, I'd like to thank my patient and loving mother, who understands the massive amount of work required to write such a book, supports my efforts by tak- ing care of my homes and 11 birds, listens to my occasional grumblings, offers commentary and feedback, when asked, and praises and motivates when and as needed. I love you, Mom, and thank you for always being there! This page intentionally left blank Introduction: Understanding the Broadband Evolution I love telecommunications It is 