ptg From the Library of Athicom Parinayakosol ptg What you should already have to get the most out of this book… • Familiarity with computer basics • Basic knowledge of computer operating systems Some books that may help… Sams Teach Yourself Microsoft Windows Vista All in One ISBN 0-672-32889-5 A quick, easy introduction to Windows Sams Teach Yourself PHP, MySQL, and Apache All in One ISBN 0-672-32976-X A step-by-step approach to basic setup and creation of interactive web applications Possible titles to look for… Sams Teach Yourself Unix System Administration in 24 Hours ISBN 0-672-32398-2 An introduction to managing a Unix system Where to go from here… • Learn to automate system administration tasks with scripting • Expand your system administration skills in Unix Related titles… Sams Teach Yourself Networking in 24 Hours ISBN 0-672-32608-6 A solid introduction to networking technology Sams Teach Yourself Shell Programming in 24 Hours ISBN 0-672-32358-3 An easy-to-understand guide to Unix scripting Sams Teach Yourself Network Troubleshooting in 24 Hours ISBN 0-672-32373-7 A beginner’s guide to finding and fixing network problems What this book will help you learn… • How to set up and administer a TCP/IP network • How to troubleshoot network problems Sams TeachYourself TCP / IP 24 in Hours From the Library of Athicom Parinayakosol ptg 800 East 96th Street, Indianapolis, Indiana, 46240 USA Joe Casad Sams TeachYourself 24 in Hours TCP/IP From the Library of Athicom Parinayakosol ptg Sams Teach Yourself TCP/IP in 24 Hours Copyright © 2009 by Pearson Education, Inc. 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 patent liability 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. ISBN-13: 978-0-672-32996-8 ISBN-10: 0-672-32996-4 Library of Congress Cataloging-in-Publication Data: Casad, Joe, 1958- Sams teach yourself TCP/IP in 24 hours / Joe Casad. — 4th ed. p. cm. Includes index. ISBN-13: 978-0-672-32996-8 (pbk.) ISBN-10: 0-672-32996-4 (pbk.) 1. TCP/IP (Computer network protocol) I. Title. II. Title: Teach yourself TCP/IP in 24 hours. III. Title: TCP/IP in 24 hours. TK5105.585.C37 2009 005.7’1376—dc22 2008031826 Printed in the United States of America First Printing September 2008 Trademarks All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Sams Publishing cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark. Warning and Disclaimer Every effort has been made to make this book as complete and as accurate as possible, but no warranty or fitness is implied. The information provided is on an “as is” basis. The author and the publisher shall have neither liability nor responsibility to any person or entity with respect to any loss or damages arising from the information contained in this book. Bulk Sales Sams Publishing offers excellent discounts on this book when ordered in quantity for bulk pur- chases or special sales. For more information, please contact U.S. Corporate and Government Sales 1-800-382-3419 corpsales@pearsontechgroup.com For sales outside of the U.S., please contact International Sales international@pearson.com Editor-in-Chief Mark Taub Acquisitions Editor Trina MacDonald Development Editor Michael Thurston Managing Editor Kristy Hart Project Editor Betsy Harris Indexer Lisa Stumpf Proofreader San Dee Phillips Technical Editor Ravi Prakash Publishing Coordinator Olivia Basegio Book Designer Gary Adair Compositor Nonie Ratcliff From the Library of Athicom Parinayakosol ptg Contents at a Glance Part I: TCP/IP Basics HOUR 1 What Is TCP/IP? 7 2 How TCP/IP Works 21 Part II: The TCP/IP Protocol System HOUR 3 The Network Access Layer 35 4 The Internet Layer 47 5 Subnetting and CIDR 69 6 The Transport Layer 83 7 The Application Layer 107 Part III: Networking with TCP/IP HOUR 8 Routing 121 9 Getting Connected 143 10 Firewalls 175 11 Name Resolution 185 12 Automatic Configuration 215 13 IPv6—The Next Generation 229 Part IV: TCP/IP Utilities HOUR 14 TCP/IP Utilities 243 15 Monitoring and Remote Access 275 Part V: TCP/IP and the Internet HOUR 16 The Internet: A Closer Look 297 17 HTTP, HTML, and the World Wide Web 305 18 Email 321 19 Streaming and Casting 339 From the Library of Athicom Parinayakosol ptg Part VI: Advanced Topics HOUR 20 Web Services 353 21 The New Web 363 22 Network Intrusion 375 23 TCP/IP Security 391 24 Implementing a TCP/IP Network—Seven Days in the Life of a Sys Admin 413 Index 425 iv Sams Teach Yourself TPC/IP in 24 Hours From the Library of Athicom Parinayakosol ptg Table of Contents Introduction 1 Part I: TCP/IP Basics HOUR 1: What Is TCP/IP? 7 Networks and Protocols 8 The Development of TCP/IP 10 TCP/IP Features 12 Standards Organizations and RFCs 17 Summary 18 Q&A 19 Key Terms 19 HOUR 2: How TCP/IP Works 21 The TCP/IP Protocol System 22 TCP/IP and the OSI Model 24 Data Packages 26 A Quick Look at TCP/IP Networking 28 Summary 30 Q&A 30 Key Terms 31 Part II: The TCP/IP Protocol System HOUR 3: The Network Access Layer 35 Protocols and Hardware 35 The Network Access Layer and the OSI Model 37 Network Architecture 38 Physical Addressing 40 From the Library of Athicom Parinayakosol ptg Ethernet 41 Anatomy of an Ethernet Frame 43 Summary 44 Q&A 44 Key Terms 45 HOUR 4: The Internet Layer 47 Addressing and Delivering 48 Internet Protocol (IP) 50 Address Resolution Protocol (ARP) 62 Reverse ARP (RARP) 63 Internet Control Message Protocol (ICMP) 63 Other Internet Layer Protocols 64 Summary 65 Q&A 65 Workshop 66 Key Terms 66 HOUR 5: Subnetting and CIDR 69 Subnets 69 Dividing the Network 70 Converting a Subnet Mask to Dotted Decimal Notation 73 Working with Subnets 75 Classless Internet Domain Routing (CIDR) 80 Summary 81 Q&A 81 Key Terms 82 HOUR 6: The Transport Layer 83 Introducing the Transport Layer 84 Transport Layer Concepts 85 Understanding TCP and UDP 91 Firewalls and Ports 101 vi Sams Teach Yourself TPC/IP in 24 Hours From the Library of Athicom Parinayakosol ptg Summary 102 Q&A 103 Key Terms 104 HOUR 7: The Application Layer 107 What Is the Application Layer? 107 The TCP/IP Application Layer and OSI 108 Network Services 109 APIs and the Application Layer 114 TCP/IP Utilities 115 Summary 116 Q&A 116 Key Terms 117 Part III: Networking with TCP/IP HOUR 8: Routing 121 Routing in TCP/IP 121 Routing on Complex Networks 134 Examining Interior Routers 136 Classless Routing 138 Higher in the Stack 139 Summary 140 Q&A 140 Key Terms 141 HOUR 9: Getting Connected 143 Dial-Up Networking 144 Cable Broadband 151 Digital Subscriber Line (DSL) 153 Wide Area Networks (WANs) 154 Wireless Networking 155 Connectivity Devices 167 Contents vii From the Library of Athicom Parinayakosol ptg Summary 171 Q&A 171 Key Terms 172 HOUR 10: Firewalls 175 What Is a Firewall? 175 Firewall Options 177 The DMZ 178 Firewall Rules 180 Proxy Service 181 Reverse Proxy 182 Summary 183 Q&A 183 Key Terms 184 HOUR 11: Name Resolution 185 What Is Name Resolution? 185 Name Resolution Using Hosts Files 187 DNS Name Resolution 189 Registering a Domain 195 Managing DNS 196 Dynamic DNS 203 NetBIOS Name Resolution 204 Summary 211 Q&A 211 Workshop 212 Key Terms 212 HOUR 12: Automatic Configuration 215 The Case for Server-Supplied IP Addresses 215 What Is DHCP? 216 How DHCP Works 217 Configuring DHCP 220 DHCP Server Configuration 221 viii Sams Teach Yourself TPC/IP in 24 Hours From the Library of Athicom Parinayakosol [...]... and TCP/ IP security Part VI ends with a case study showing how the components of TCP/ IP interact in a real working environment The concepts in this book, like TCP/ IP itself, are independent of a system and descend from the standards defined in Internet Requests for Comment (RFCs) How This Book Is Organized Each hour in Sams Teach Yourself TCP/ IP in 24 Hours, Fourth Edition, begins with a quick introduction... routing functions shown in Figure 1. 4 By the Way Name Resolution Although the numeric IP address is probably more user-friendly than the network adapter’s prefabricated physical address, the IP address is still designed for the convenience of the computer rather than the convenience of the user People might have trouble remembering whether a computer’s address is 11 1 .12 1 .13 1 .14 6 or 11 1 .12 1 .13 1 .15 6 TCP/ IP, ... From the Library of Athicom Parinayakosol PART I TCP/ IP Basics HOUR 1 What Is TCP/ IP? HOUR 2 How TCP/ IP Works 7 21 From the Library of Athicom Parinayakosol This page intentionally left blank From the Library of Athicom Parinayakosol HOUR 1 What Is TCP/ IP? What You’ll Learn in This Hour: Networks and network protocols History of TCP/ IP Important features of TCP/ IP TCP/ IP is a protocol system—a collection... the protocols that operate at each of TCP/ IP s layers From the Library of Athicom Parinayakosol 2 Sams Teach Yourself TCP/ IP in 24 Hours Part III, “Networking with TCP/ IP, ” describes some of the devices, services, and utilities necessary for supporting TCP/ IP networks You learn about routing and network hardware, DHCP, DNS, and IPv6 Part IV, TCP/ IP Utilities,” introduces some of the common utilities... layers of the TCP/ IP model providing services for other layers In fact, it is not the TCP/ IP model that provides services The TCP/ IP model defines the services that should be provided The vendor software implementations of TCP/ IP actually provide these services By the Way From the Library of Athicom Parinayakosol 10 HOUR 1: What Is TCP/ IP? The Development of TCP/ IP Present-day TCP/ IP networking represents... and TCP/ IP s Application layer in Hour 7, “The Application Layer.” The TCP/ IP suite also includes a number of ready-made applications designed to assist with various network tasks Some typical TCP/ IP utilities are shown in Table 1. 1 You’ll learn more about these TCP/ IP utilities in Hour 14 , TCP/ IP Utilities.” From the Library of Athicom Parinayakosol Standards Organizations and RFCs TABLE 1. 1 17 Typical... and all Unix variants are fluent in TCP/ IP The recent popularity of Unix-based systems such as Linux, BSD, Solaris, and Apple OS X has increased the dominance of TCP/ IP in the networking world From the Library of Athicom Parinayakosol 12 By the Way HOUR 1: What Is TCP/ IP? The term gateway is used inconsistently in discussions of TCP/ IP A gateway is sometimes just an ordinary router that connects a LAN... participate in a TCP/ IP network As you read this book, be aware of the following distinction: A TCP/ IP standard is a system of rules defining communication on TCP/ IP networks A TCP/ IP implementation is a software component that performs the functions that enable a computer to participate in a TCP/ IP network Application Application Layer FIGURE 1. 2 Application Application Layer Transport Layer Internet... into six parts Each part brings you a step closer to mastering the goal of proficiency in TCP/ IP Part I, TCP/ IP Basics,” introduces you to TCP/ IP and the TCP/ IP protocol stack Part II, “The TCP/ IP Protocol System,” takes a close look at each of TCP/ IP s protocol layers: the Network Access, Internet, Transport, and Application layers You learn about IP addressing and subnetting, as well as physical... Library of Athicom Parinayakosol This page intentionally left blank From the Library of Athicom Parinayakosol Introduction Welcome to Sams Teach Yourself TCP/ IP in 24 Hours, Fourth Edition This book provides a clear and concise introduction to TCP/ IP for newcomers, and also for users who have worked with TCP/ IP but would like a little more of the inside story The fourth edition includes new material . OSI 10 8 Network Services 10 9 APIs and the Application Layer 11 4 TCP/ IP Utilities 11 5 Summary 11 6 Q&A 11 6 Key Terms 11 7 Part III: Networking with TCP/ IP HOUR 8: Routing 12 1 Routing in TCP/ IP. 353 21 The New Web 363 22 Network Intrusion 375 23 TCP/ IP Security 3 91 24 Implementing a TCP/ IP Network—Seven Days in the Life of a Sys Admin 413 Index 425 iv Sams Teach Yourself TPC /IP in 24. TCP/ IP 12 1 Routing on Complex Networks 13 4 Examining Interior Routers 13 6 Classless Routing 13 8 Higher in the Stack 13 9 Summary 14 0 Q&A 14 0 Key Terms 14 1 HOUR 9: Getting Connected 14 3 Dial-Up