ecommunications essentials : the complete global source / Lillian Goleniewski ; edited by Kitty Wilson Jarrett. - 2nd ed. p. cm. Includes index. ISBN 0-321-42761-0 (pbk. : alk. paper) 1. Telecommunication. I. Jarrett, Kitty Wilson. II. Title. TK5101.G598 2006 621.382-dc22 2006022505 Copyright © 2007 Pearson Education, Inc. All rights reserved. Printed in the United States of America. This publication is protected by copyright, and permission must be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permissions, write to: Pearson Education, Inc. Rights and Contracts Department 75 Arlington Street, Suite 300 Boston, MA 02116 Fax: (617) 848-7047 ISBN 0-321-42761-0 Text printed in the United States on recycled paper at Courier in Stoughton, Massachusetts. First printing, October 2006 This book is dedicated to those eager to master the arts and sciences of telecommunications and to those seeking to gain a deeper understanding and appreciation of the vital role of information and communications technologies. I welcome you to the study of one of the most critical infrastructures of the twenty-first century and applaud your undertaking. I know you will find the universe of ICT to be as vast and full of potential as I do, and I hope this stimulates you to continue learning all you can about the wonderful world of telecommunications! This page intentionally left blank Contents About the Author About LIDO xxiii Acknowledgments Introduction: Understanding the Broadband Evolution Part I Communications Fundamentals Chapter 1 Telecommunications Technology Fundamentals Transmission Lines Circuits Channels Lines and Trunks Virtual Circuits Types of Network Connections The Electromagnetic Spectrum and Bandwidth The Electromagnetic Spectrum Bandwidth Analog and Digital Transmission Analog Transmission Digital Transmission Contents Analog Versus Digital Tr