Tcp Ip

TCP/IP Primer Plus
Heather Osterloh

201 West 103rd St., Indianapolis, Indiana, 46290 USA

TCP/IP Primer Plus
Copyright © 2002 by Sams Publishing All rights reserved. No part of this book shall be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without written permission from the publisher. No patentliability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this book, the publisher and author assume no responsibility for errors or omissions. Nor is any liability assumed for damages resulting from the use of the information contained herein. International Standard Book Number: 0-672-32208-0 Library of CongressCatalog Card Number: 2001093492 Printed in the United States of America First Printing: September 2001 04 03 02 01 4 3 2 1

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INDEXER

Trademarks
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CONTENTS AT A GLANCE
INTRODUTION
CHAPTER 1 CHAPTER 2 CHAPTER 3 CHAPTER 4 CHAPTER 5 CHAPTER 6 CHAPTER 7 CHAPTER 8 CHAPTER 9 CHAPTER 10 CHAPTER 11 CHAPTER 12 CHAPTER 13 CHAPTER 14 CHAPTER 15 CHAPTER 16 CHAPTER 17 CHAPTER 18 APPENDIX A APPENDIX B APPENDIX C APPENDIX D APPENDIX E

1 Overview ofIndustry Models and Standards . . . . . . . . . . . . . . . . . .3 IP Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33 Network Layer/Internet Protocols . . . . . . . . . . . . . . . . . . . . . . . . .61 Address Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89 IP Routing . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .125 Routing Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .137 Transport/Host-to-Host Layer . . . . . . . . . . . . . . . . . . . . . . . . . . .203 Transmission Control Protocol (TCP) . . . . . . . . . . . . . . . . . . . . .211 User Datagram Protocol (UDP) . . . . . . . . . . . . . . . . . . . . . . . . . .241 Upper-layerProtocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .249 Telnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .257 File Transfer Protocol (FTP) . . . . . . . . . . . . . . . . . . . . . . . . . . . .269 Simple Mail Transfer Protocol (SMTP) . . . . . . . . . . . . . . . . . . . . .287 Name Resolution . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . .299 HyperText Transfer Protocol (HTTP) . . . . . . . . . . . . . . . . . . . . . .321 Trivial File Transfer Protocol (TFTP) . . . . . . . . . . . . . . . . . . . . . .335 Simple Network Management Protocol (SNMP) . . . . . . . . . . . . .345 Open Network Computing Protocols . . . . . . . . . . . . . . . . . . . . .353 Request for Comments (RFCs) . . . . . . . . ....