An Engmeerin A D D Approach to I S O N - W nmputcr Networkin, E S L E Y ATM Networks, the Internet, P R O F and the Telephone Network E S S I O N A S. Kesha L C O -TT M P U T I N G S E R I E S ESI Blackburn College Library 01254 292120 BLACKBURN COLL LG l Please return this book on or before the last date below An Engineering Approach to Computer Networking: ATM Networks, the Internet, and the Telephone Network Addison-Wesley Professional Computing Series__ Brian W. Kernighan, Consulting Editor Ken Arnold/John Peyton, A C User's Guide to ANSI C Matthew H. Austern, Generic Programming and the STL: Using and Extending the C++ Standard Template Library David R. Butenhof, Programming with POSIX® Threads Brent Callaghan, NFS Illustrated Tom Cargill, C++ Programming Style William R. Cheswick/Steven M. Bellovin, Firewalls and Internet Security: Repelling the Wily Hacker David A. 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Keshav AT&T Labs-Research ▲ ▼T ADDISON-WESLEY Boston • San Francisco • New York • Toronto • Montreal London • Munich • Paris • Madrid Capetown • Sydney • Tokyo • Singapore • Mexico City Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and we were aware of a trademark claim, the designations have been printed in initial capital letters or in all capitals. The author and publisher have taken care in the preparation of this book, but make no expressed or implied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of the use of the information or programs contained herein. The publisher offers discounts on this book when ordered in quantity for special sales. For more informa¬ tion, please contact: Pearson Education Corporate Sales Division One Lake Street Upper Saddle River, NJ 07458 (800) 382-3419 corpsales@ pearsontechgroup .com Visit AW on the Web: www.awl.com/cseng/ Library of Congress Cataloging-in-Publication Keshav, Srinivasan. An engineering approach to computer networking : ATM networks, the internet, and the telephone network / S. Keshav. p. cm. - (Addison-Wesley professional computing series) Includes bibliographical references and index. ISBN 0-201-63442-2 1. Computer networks. 2. Asynchronous transfer mode. 3. Internet (Computer network) 4. Telephone systems. I. Title. II. Series. TK5105.5.K48 1997 004.6—dc21 97-8249 CIP AT&T Copyright © 1997 by AT&T. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form, or by any means, electronic, mechanical, photocopying, recording, or other¬ wise, without the prior consent of the publisher. Printed in the United States of America. Published simultaneously in Canada. ISBN 0201634422 Text printed on recycled paper 7 8 9 10 11-CRW-0403020100 7th printing, November 2000 To Appa and Amma, Nicole and Maya c