01_599399_ffirs.qxd 8/18/05 11:48 PM Page i Networking ALL-IN-ONE DESK REFERENCE FOR DUMmIES ‰ 2 ND EDITION by Doug Lowe 01_599399_ffirs.qxd 8/18/05 11:48 PM Page iv 01_599399_ffirs.qxd 8/18/05 11:48 PM Page i Networking ALL-IN-ONE DESK REFERENCE FOR DUMmIES ‰ 2 ND EDITION by Doug Lowe 01_599399_ffirs.qxd 8/18/05 11:48 PM Page ii Networking All-in-One Desk Reference For Dummies®, 2nd Edition Published by Wiley Publishing, Inc. 111 River Street Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2005 by Wiley Publishing, Inc., Indianapolis, Indiana Published by Wiley Publishing, Inc., Indianapolis, Indiana Published simultaneously in Canada 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, scanning or otherwise, except as permit- ted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. 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Library of Congress Control Number: 2005927615 ISBN-13: 978-0-7645-9939-2 ISBN-10: 0-7645-9939-9 Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 2O/QX/QZ/QV/IN 01_599399_ffirs.qxd 8/18/05 11:48 PM Page iii About the Author Doug Lowehas written a whole bunch of computer books, including more than 35 For Dummiesbooks, among them Networking For Dummies, 7th Edition, Java All-in-One Desk Reference For Dummies, PowerPoint 2003 For Dummies, and Word 2003 All-in-One Desk Reference For Dummies. He lives in sunny Fresno, California, where the motto is “No, we aren’t really the Armpit of California,” with his wife, the youngest of his three daughters, and a goofy- looking six-month-old Shar-Pei/Black Lab mix named Lucy. He’s one of those obsessive-compulsive decorating nuts who puts up tens of thousands of lights at Christmas and creates computer-controlled Halloween decorations that rival Disney’s Haunted Mansion. Last year he actually built a pirate ship in his backyard. 01_599399_ffirs.qxd 8/18/05 11:48 PM Page iv 01_599399_ffirs.qxd 8/18/05 11:48 PM Page v Dedication To Debbie, Rebecca, Sarah, and Bethany. Author’s Acknowledgments I’d like to start by thanking everyone who was involved with the second edi- tion of this book, especially project editor Christopher Morris, who heeded the Hitchhiker’s Guidecreed (“Don’t panic!”) when I was occasionally late with submissions and who did a great job following through on all the little edito- rial details needed to put a book of this scope together on time. Thanks also to Dan DiNicolo, who gave the manuscript a thorough review and offered many excellent suggestions for improvements, and to copy editors Jean Rogers and Andy Hollandbeck, who whipped my prose into shape, crossing all the i’s and dotting all the t’s, or something like that. And, as always, thanks to all the behind-the-scenes people who chipped in with help I’m not even aware of. 01_599399_ffirs.qxd 8/18/05 11:48 PM Page vi Publisher’s Acknowledgments We’re proud of this book; please send us your comments through our online registration form located at www.dummies.com/register/. Some of the people who helped bring this book to market include the following: Acquisitions, Editorial, and Composition Services Media Development Project Coordinator: Adrienne Martinez Project Editor:Christopher Morris Layout and Graphics: Andrea Dahl, Acquisitions Editor:Melody Layne Lauren Goddard, Denny Hager, Stephanie D. Jumper, Heather Ryan, Copy Editors:Jean Rogers, Andy Hollandbeck Mary Gillot Virgin Technical Editor:Dan DiNicolo Proofreaders: Leeann Harney, Jessica Kramer, Editorial Manager:Kevin Kirschner Joe Niesen, Dwight Ramsey, Evelyn W. Still Media Development Supervisor: Indexer: Infodex Indexing Services Inc. Richard Graves Editorial Assistant:Amanda Foxworth Cartoons:Rich Tennant (www.the5thwave.com) Publishing and Editorial for Technology Dummies Richard Swadley,Vice President and Executive Group Publisher Andy Cummings,Vice President and Publisher Mary Bednarek,Executive Acquisitions Director Mary C. Corder,Editorial Director Publishing for Consumer Dummies Diane Graves Steele,Vice President and Publisher Joyce Pepple,Acquisitions Director Composition Services Gerry Fahey,Vice President of Production Services Debbie Stailey,Director of Composition Services 02_599399_ftoc.qxd 8/18/05 11:49 PM Page vii Contents at a Glance Introduction ................................................................1 Book I: Networking Basics ...........................................7 Chapter 1: Understanding Networks ...............................................................................9 Chapter 2: Understanding Network Protocols and Standards ..................................19 Chapter 3: Understanding Network Hardware ............................................................41 Chapter 4: Understanding Network Operating Systems ............................................59 Book II: Building a Network .......................................75 Chapter 1: Planning a Network ......................................................................................77 Chapter 2: Installing Network Hardware ......................................................................95 Chapter 3: Setting Up a Network Server .....................................................................111 Chapter 4: Configuring Client Computers ..................................................................127 Chapter 5: Configuring Other Network Features .......................................................139 Chapter 6: Verifying Your Network Installation .........................................................151 Book III: Network Administration and Security ..........157 Chapter 1: Help Wanted: Job Description for a Network Administrator ................159 Chapter 2: Security 101 .................................................................................................173 Chapter 3: Managing User Accounts ...........................................................................183 Chapter 4: Firewalls and Virus Protection .................................................................191 Book IV: Network Troubleshooting and Disaster Planning ..............................................203 Chapter 1: Solving Network Problems ........................................................................205 Chapter 2: Network Performance Anxiety .................................................................219 Chapter 3: Protecting Your Network ...........................................................................229 Chapter 4: Disaster Recovery and Business Continuity Planning ..........................239 Chapter 5: Dealing with Dysfunctional E-Mail ............................................................247 Book V: TCP/IP and the Internet ...............................255 Chapter 1: Introduction to TCP/IP and the Internet .................................................257 Chapter 2: Understanding IP Addresses .....................................................................265 Chapter 3: Using DHCP .................................................................................................283 Chapter 4: Using DNS ....................................................................................................297 Chapter 5: Using FTP .....................................................................................................321 Chapter 6: TCP/IP Tools and Commands ...................................................................343