00_575252 ffirs.qxd 9/2/04 3:49 PM Page i
Wireless Networks FOR DUMmIES‰
by Barry Lewis and Peter T.Davis 00_575252 ffirs.qxd 9/2/04 3:49 PM Page iv 00_575252 ffirs.qxd 9/2/04 3:49 PM Page i
Wireless Networks FOR DUMmIES‰
by Barry Lewis and Peter T.Davis 00_575252 ffirs.qxd 9/2/04 3:49 PM Page ii
Wireless Networks For Dummies® Published by Wiley Publishing, Inc. 111 River Street Hoboken, NJ 07030-5774 www.wiley.com Copyright © 2004 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 permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permis- sion 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. Requests to the Publisher for permission should be addressed to the Legal Department, Wiley Publishing, Inc., 10475 Crosspoint Blvd., Indianapolis, IN 46256, (317) 572-3447, fax (317) 572-4355, e-mail: brandreview@ wiley.com. Trademarks: Wiley, the Wiley Publishing logo, For Dummies, the Dummies Man logo, A Reference for the Rest of Us!, The Dummies Way, Dummies Daily, The Fun and Easy Way, Dummies.com, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries, and may not be used without written permission. All other trademarks are the property of their respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book.
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About the Author Barry D. Lewis (CISSP, CISM) has been in the information technology sector for 35 years, specializing in information security since 1980. He co-founded Cerberus Information Security Consulting in 1993 and was elevated to President of the firm shortly thereafter. He served as Secretary and then Vice President of the ISC(2) organization, past-President of the Toronto ISSA, and Chairperson of the Eastern Canada ACF2 Users Group. Barry is listed in the International Who’s Who of Entrepreneurs. Mr. Lewis lectures worldwide on computer security and audit issues and was honored with the Best Speaker Award at the annual Computer Associates Enterprise Wide Security & Audit conference (ESAC), one of North America’s largest security conferences. Mr. Lewis has written and co-authored numerous articles and seven books, including Computer Security For Dummies, and Teach Yourself Windows 2000 Server in 21 Days. He lives near Toronto with his wife Elizabeth and son Derek.
Peter T. Davis (CISA, CMA, CISSP, CWNA, CCNA, CMC, CISM) founded Peter Davis+Associates (a very original name) as a firm specializing in the security, audit, and control of information. A 29-year information systems veteran, Mr. Davis’s career includes positions as programmer, systems ana- lyst, security administrator, security planner, information systems auditor, and consultant. Peter also is the past President and founder of the Toronto ISSA chapter, past Recording Secretary of the ISSA’s International Board, and past Computer Security Institute Advisory Committee member. Mr. Davis has written or co-written numerous articles and 10 books, including Computer Security For Dummies and Securing and Controlling Cisco Routers. Peter was also the technical editor for Hacking For Dummies and Norton Internet Security For Dummies. Peter is listed in the International Who’s Who of Professionals. In addition, he was only the third Editor in the three-decade history of EDPACS, a security, audit and control publication. He finds time to be a part-time lec- turer in data communications at Seneca College (cs.senecac.on.ca). He lives with his wife Janet, daughter Kelly, two cats, and a dog in Toronto, Ontario. 00_575252 ffirs.qxd 9/2/04 3:49 PM Page iv 00_575252 ffirs.qxd 9/2/04 3:49 PM Page v
Dedication To my wife Elizabeth, who puts up with far more than I have a right to expect.
— Barry
To all my friends and enemies. Hopefully, the first group is bigger than the second.
— Peter 00_575252 ffirs.qxd 9/2/04 3:49 PM Page vi 00_575252 ffirs.qxd 9/2/04 3:49 PM Page vii
Author’s Acknowledgments We’d like to offer special thanks to Pat O’Brien, who started this rolling. Peter worked as the technical editor for Pat on Hacking For Dummies. Thanks for passing on Melody’s name.
Thanks to Melody Layne, acquisitions editor, for pitching the book to the edi- torial committee and getting us a contract. Much appreciated.
Thanks to Becky Huehls, who started us out on this project as editor but wisely got herself re-assigned. Thanks to Kelly Ewing for picking up the ball and running with it after Becky. Unfortunately, Kelly fumbled it, but Colleen Totz was able to struggle with it over the goal line.
Dan DiNicolo, technical editor, is commended for his diligence in reviewing the material. Thanks, Dan.
Peter would like to thank Kevin Beaver, Ken Cutler, Gerry Grindler, Ronnie Holland, Carl Jackson, Ray Kaplan, Kevin Kobelsky, Carrie Liddie, Dexter Mills Jr., and Larry Simon for responding to a request for wireless informa- tion. Thanks for answering the call for help. The provided information shows in this book.
Barry would like to thank his co-author Peter. Always a pleasure, sir. He would also like to acknowledge Craig McGuffin and John Tannahill who are always there for him, as friends and business associates , and never fail to lend a helping hand. 00_575252 ffirs.qxd 9/2/04 3:49 PM Page viii
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 Production Media Development Project Coordinators: Courtney MacIntyre, Project Editor: Colleen Totz, Rebecca Huehls Erin Smith Acquisitions Editor: Melody Layne Layout and Graphics: Jonelle Burns, Technical Editor: Dan DiNicolo Lauren Goddard, Denny Hager, Joyce Haughey, Stephanie D. Jumper, Editorial Manager: Carol Sheehan Michael Kruzil, Lynsey Osborn, Media Development Manager: Jacque Roth, Heather Ryan, Laura VanWinkle Ron Terry Media Development Supervisor: Proofreaders: John Greenough, Carl W. Pierce, Richard Graves Brian H. Walls Editorial Assistant: Amanda Foxworth Indexer: TECHBOOKS Production Services Cartoons: Rich Tennant, www.the5thwave.com Special Help: Kelly Ewing
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 01_575252 ftoc.qxd 9/2/04 3:50 PM Page ix
Contents at a Glance
Introduction ...... 1 Part I: Planning and Acquiring Your Network ...... 7 Chapter 1: Removing the Tethers: Entering the Wireless World ...... 9 Chapter 2: If You Fail to Plan, You Plan to Fail ...... 25 Chapter 3: Matching Wireless Technologies to Your Plan ...... 47 Part II: Implementing Your Wireless Network ...... 59 Chapter 4: Getting a Quick Start with Wireless Personal Area Networks ...... 61 Chapter 5: Moving On to a Wireless LAN: Your Wireless Access Point ...... 83 Chapter 6: Connecting Your Clients ...... 103 Chapter 7: Building the Multi-Zone Network ...... 121 Chapter 8: Using Wireless on the Road to Connect to the Office ...... 133 Part III: Using Your Network Securely ...... 147 Chapter 9: Considering a Deadbolt: Understanding the Risks of Wireless Networks ...... 149 Chapter 10: Designing a Secure Network ...... 169 Chapter 11: Maintaining Network Security ...... 185 Chapter 12: Secure Wireless Access with Virtual Private Networking ...... 209 Part IV: Keeping Your Network on the Air — Administration and Troubleshooting ...... 229 Chapter 13: Problems with Keeping on the Air ...... 231 Chapter 14: Bridging Networks to Manage Coverage ...... 249 Chapter 15: Dealing with Network Throughput Issues ...... 265 Chapter 16: It’s Ten O’Clock: Do You Know Where Your Access Points Are? ...... 283 Part V: The Part of Tens ...... 303 Chapter 17: Ten Administrator Tools and What They Do ...... 305 Chapter 18: Top Ten Ways to Secure Your Network ...... 313 Chapter 19: Ten Ways Wireless Is Used in Business ...... 327 01_575252 ftoc.qxd 9/2/04 3:50 PM Page x
Part VI: Appendixes ...... 339 Appendix A: Industry Trade Associations ...... 341 Appendix B: Wireless Standards ...... 347 Appendix C: The Fundamentals of Radio Frequency...... 353 Index ...... 371 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xi
Table of Contents
Introduction...... 1 About This Book ...... 2 How to Use This Book ...... 3 How This Book Is Organized ...... 3 Part I: Planning and Acquiring Your Network ...... 3 Part II: Implementing Your Wireless Network ...... 4 Part III: Using Your Network Securely ...... 4 Part IV: Keeping Your Network on the Air — Administration and Troubleshooting ...... 4 Part V: The Part of Tens ...... 5 Part VI: Appendixes ...... 5 Icons Used in This Book ...... 5 Where to Go from Here ...... 6
Part I: Planning and Acquiring Your Network ...... 7
Chapter 1: Removing the Tethers: Entering the Wireless World . . . . .9 Understanding the Risks and Rewards of Going Wireless ...... 10 What you risk ...... 10 The benefits you gain ...... 11 Applications of Wireless Networks ...... 11 Sorting Out the Nets: Do I Need a WPAN, WLAN, or WMAN? ...... 12 Let’s get personal: WPAN ...... 13 The holy grail of wireless networking: WLAN ...... 14 Where the rubber hits the road: WMAN ...... 15 Using Wireless Networks ...... 16 Accessing networks ...... 16 Extending the network ...... 17 Connecting buildings ...... 17 Going mobile ...... 18 Getting mail on the road ...... 19 Turning a Notion into a Network ...... 20 Planning your wireless network ...... 20 Installing your wireless network ...... 20 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xii
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Configuring a wireless network ...... 21 Staying secure in the wireless world ...... 22 Administering and maintaining a wireless network ...... 22 Convergence of Wireless Technologies — What Will the Future Hold? ...... 23 Chapter 2: If You Fail to Plan, You Plan to Fail ...... 25 Evaluating Your Wireless Needs ...... 25 What is my environment? ...... 26 What is my budget? ...... 26 How many clients do I expect? ...... 27 Where will they want to access the network? ...... 28 What does the data look like? ...... 28 What technology do I want to use? ...... 29 Do I need to protect the data? ...... 31 What coverage do I need? ...... 31 Preparing for a Site Survey ...... 32 Analyzing your facility ...... 33 Working with existing networks ...... 33 Area coverage ...... 34 Purpose and business requirements ...... 36 Bandwidth and roaming requirements ...... 37 Available resources ...... 37 Security needs analysis ...... 38 Developing a site survey checklist ...... 38 Using Site Survey Equipment to Get It Right ...... 39 Doing That Site Survey ...... 41 Analyzing your indoor network ...... 42 Analyzing your outdoor network ...... 42 Calculating a link budget ...... 42 Describing Your Final Plan in a Site Survey Report ...... 45 Defining the business requirements and methodology ...... 45 Documenting the requirements ...... 46 Chapter 3: Matching Wireless Technologies to Your Plan ...... 47 Choosing the Right Networking Hardware ...... 47 Are You Being Served? IBSS, BSS, and ESS ...... 50 Selecting the Wireless Mode ...... 51 Considering ad hoc mode ...... 51 Using infrastructure mode ...... 52 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xiii
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Gearing Up to Send and Receive Signals ...... 52 Frequencies and spectrums ...... 53 Get the right antennae ...... 54 Introducing the zone — a wireless diet ...... 56 Understanding and Using Layer 2 and 3 Concepts ...... 57
Part II: Implementing Your Wireless Network ...... 59
Chapter 4: Getting a Quick Start with Wireless Personal Area Networks ...... 61 Understanding IrDA ...... 61 Installing infrared devices ...... 63 Using IrDA to transfer data ...... 64 Securing IrDA ...... 66 Understanding Bluetooth ...... 67 Adding Bluetooth capabilities ...... 71 Securing Bluetooth ...... 74 Protecting Bluetooth networks ...... 75 IrDA and Bluetooth Comparison ...... 82 Chapter 5: Moving On to a Wireless LAN: Your Wireless Access Point ...... 83 Parts Is Parts — Do You Have Them All? ...... 83 Connecting and Configuring Your Access Point ...... 84 Connecting the access point ...... 85 Configure your browser ...... 86 Changing the default network settings ...... 87 Initial Setup and Testing ...... 88 Deciding on initial setup options ...... 88 Performing the advanced setup functions ...... 92 Back up your work ...... 94 Turning Off the Defaults ...... 94 Changing the password ...... 95 Changing the access point name ...... 95 Changing security options ...... 96 Understanding the other options ...... 98 Configuration and setup of a Cisco Aironet 1200 ...... 99 Testing the Signal ...... 102 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xiv
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Chapter 6: Connecting Your Clients ...... 103 Adding Hardware to the PC ...... 104 Peripheral Component Interconnect (PCI) ...... 105 Universal Serial Bus (USB) ...... 106 Ethernet client adapter ...... 106 The final decision ...... 107 Wireless print server ...... 108 Installing the Wireless Hardware ...... 109 Upgrading the firmware or software ...... 109 Important guidelines for upgrading ...... 111 Configuring the Client’s Operating System ...... 112 Configuring Windows XP Professional clients ...... 112 Configuring Windows 2000 clients ...... 114 Configuring Mac OS clients ...... 117 Configuring your Centrino systems ...... 118 Configuring Linux and FreeBSD Clients ...... 119 Making Sure the Connection Works ...... 120 Chapter 7: Building the Multi-Zone Network ...... 121 Roaming Around with a Wireless Machine ...... 121 Wireless roaming standards ...... 122 Connectivity issues as you move around ...... 126 Reassociation — Getting back together as you move from AP to AP ...... 129 Load Balancing — Are All Zones Used Equally? ...... 131 Chapter 8: Using Wireless on the Road to Connect to the Office ...... 133 Spontaneous Communities: Ad Hoc Networks ...... 133 Wi-Fi Warriors on the Road ...... 134 Wireless at the airport ...... 135 Wireless in hotels ...... 136 E-Mailing Wirelessly with Microsoft Exchange ...... 137 Setting up POP access ...... 138 Connecting directly to Exchange ...... 140 Wireless Hot Spots: What’s New Around the World? ...... 144 In the air ...... 145 New ideas for wireless network attacks ...... 146 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xv
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Part III: Using Your Network Securely ...... 147
Chapter 9: Considering a Deadbolt: Understanding the Risks of Wireless Networks ...... 149 Risks to the Network ...... 149 Going to war: War nibbling, war driving, war flying, and war chalking ...... 150 A roguish WLAN ...... 156 Open broadcast of SSIDs ...... 156 Jamming ...... 157 Signal loss ...... 158 Risks to Your Users ...... 160 Target profiling ...... 160 Identity theft ...... 160 Lack of authentication ...... 161 Default passwords are de fault ...... 162 Risks to Your Data ...... 163 You call that encryption?! ...... 164 Accidental associations ...... 165 Eavesdropping ...... 165 Man-in-the-middle attacks ...... 166 Hijacking ...... 166 Chapter 10: Designing a Secure Network ...... 169 Security as a Cost of Doing Business ...... 170 Developing a Security Architecture ...... 171 Developing a Wireless Security Policy ...... 173 Developing Wireless Security Standards ...... 175 Developing Wireless Security Best Practices ...... 176 General best practices ...... 176 Access point best practices ...... 177 Password best practices ...... 178 SSID best practices ...... 178 Authentication best practices ...... 178 Encryption best practices ...... 179 Client best practices ...... 179 Network best practices ...... 180 Managing Your Wireless Security Policy ...... 181 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xvi
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Designing a Secure Network ...... 182 Performing a Risk Analysis ...... 182 Chapter 11: Maintaining Network Security ...... 185 Understanding Security Mechanisms ...... 186 Three States of Authentication ...... 187 Authentication ...... 187 Protecting Privacy ...... 189 Protecting Message Integrity ...... 190 Filtering the Chaff ...... 191 SSID filtering ...... 191 MAC filtering ...... 191 Protocol filtering ...... 193 Using Encryption ...... 193 Hip to WEP ...... 194 WEP weaknesses ...... 196 Attacking WEP ...... 198 Key management problems ...... 199 Protecting WEP Keys ...... 200 Default WEP keys ...... 200 Using WPA ...... 202 AES-CCMP ...... 204 Using Port Authentication ...... 204 Using LEAP, PEAP, and other forms of EAP ...... 206 EAP Questions ...... 207 Chapter 12: Secure Wireless Access with Virtual Private Networking ...... 209 Secure Access with a VPN ...... 209 Defining the VPN ...... 211 VPN considerations ...... 213 Understanding tunneling ...... 214 Deploying VPNs in WLANs ...... 216 Wireless VLANs ...... 217 Various Other Methods for Secure Access ...... 218 Using Microsoft’s Point-to-Point Tunneling Protocol ...... 218 Considering Layer 2 Tunneling Protocol ...... 225 Using Windows IPSec ...... 225 Oldies but goodies — SSH2 ...... 226 Who Is Doing the Talking? ...... 228 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xvii
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Part IV: Keeping Your Network on the Air — Administration and Troubleshooting ...... 229
Chapter 13: Problems with Keeping on the Air ...... 231 Troubleshooting Redux ...... 231 Am I in Your Fresnel Zone? ...... 234 Multipath Interference ...... 236 You Can’t Go That Far: Free Space Loss ...... 238 Contention-Free Frames ...... 239 Hidden Node — So Where Is It? ...... 241 Managing Power ...... 243 Power over Ethernet (PoE) ...... 244 Calculating your Power Budget ...... 245 Chapter 14: Bridging Networks to Manage Coverage ...... 249 Using That Site Survey ...... 250 Bridges and Switches and Routers, Oh My! ...... 250 Understanding Wireless Bridges ...... 251 Using root mode ...... 254 Using non-root mode ...... 254 Using access point mode ...... 255 Using repeater mode ...... 255 Wireless Workgroup Bridge ...... 255 Going to the Movies: A Bridge Too Far? ...... 257 Building Hardware Bridges ...... 258 Bridging the Gap: Getting Started ...... 259 Troubleshooting Your Bridged Network ...... 260 Building Network Bridges in Windows XP ...... 260 Creating a network bridge ...... 261 Troubleshooting a wireless bridge ...... 262 Using Wireless Switches ...... 262 Chapter 15: Dealing with Network Throughput Issues ...... 265 Watching Traffic ...... 265 Estimating network performance ...... 266 Sniffing your traffic ...... 272 Traffic management and analysis ...... 277 Outsourcing your network management ...... 278 Monitoring the Network for Trouble Spots ...... 279 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xviii
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Chapter 16: It’s Ten O’Clock: Do You Know Where Your Access Points Are? ...... 283 Discovering the Extent of Your Wireless Network ...... 283 Using programs that came with your operating system ...... 284 Using utilities that came with your network adapter ...... 284 Using war driving or network discovery tools ...... 285 Using traffic management and analysis tools ...... 286 Using network management tools ...... 287 Using vulnerability testing software ...... 289 Detecting Wireless Intrusion ...... 291 Incident Response and Handling ...... 299 Auditing Activities ...... 300
Part V: The Part of Tens ...... 303
Chapter 17: Ten Administrator Tools and What They Do ...... 305 Using Ethereal to Look at Traffic ...... 306 Stumbling on Networks with NetStumbler ...... 306 With Luck, You Can Find Networks with Kismet ...... 308 Surfing for Networks with Wellenreiter ...... 308 Using AirSnort to Obtain WEP Keys ...... 309 Rooting Around with THC-RUT ...... 309 Cracking Encryption with WEPCrack ...... 310 Getting a MAC Address ...... 310 Creating Sham Access Points with FakeAP ...... 311 Let’s Sneak a Peek with AiroPeek, Shall We? ...... 312 Chapter 18: Top Ten Ways to Secure Your Network ...... 313 Using the Highest Level of Encryption ...... 314 Changing the Default SSID ...... 315 Looking for Rogue WAPs ...... 315 Disabling Ad Hoc Mode ...... 317 Disabling SNMP or Select Strong String ...... 317 Turning Down the Power ...... 319 Securing WAPs with a Subnet and a Firewall ...... 321 Using a WIDS ...... 325 Disabling Wired Access from Public Areas ...... 325 Hardening the Access Point and Clients ...... 326 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xix
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Chapter 19: Ten Ways Wireless Is Used in Business ...... 327 Attending Meetings with Tablet PCs ...... 327 Getting Your E-mail As You Wander the Building ...... 329 Getting Corporate Access in the Lunchroom ...... 329 Setting Up Wireless Conference Rooms ...... 329 Querying Your Corporate Database ...... 331 Keeping in Touch at the Airport ...... 331 Maintaining a Presence While Having Coffee ...... 332 Using Bluetooth Phones in Your Car ...... 334 Accessing a Wireless Network in Your Hotel ...... 335 Using the Phone to Check Your Stocks ...... 338
Part VI: Appendixes ...... 339
Appendix A: Industry Trade Associations ...... 341 Government Organizations ...... 341 International Standards Organizations ...... 342 Wireless-Related Organizations and Associations ...... 343 Local Wireless Groups ...... 345 Other Industry Associations ...... 346 Appendix B: Wireless Standards ...... 347 802.1x ...... 347 802.11 ...... 348 802.11a ...... 348 802.11b ...... 348 802.11c ...... 349 802.11d ...... 349 802.11e ...... 349 802.11f ...... 349 802.11g ...... 350 802.11h ...... 350 802.11i ...... 350 802.11j ...... 350 802.11k ...... 351 802.11n ...... 351 802.15 ...... 351 802.16 ...... 352 01_575252 ftoc.qxd 9/2/04 3:50 PM Page xx
xx Wireless Networks For Dummies
Appendix C: The Fundamentals of Radio Frequency ...... 353 Radio Frequency ...... 353 Behavior of Radio Waves ...... 360 Gain ...... 360 Loss ...... 360 Reflection ...... 361 Refraction ...... 361 Diffraction ...... 361 Scattering ...... 361 Absorption ...... 362 Free space loss ...... 362 Fresnel zone ...... 362 RF Units of Measure ...... 362 Watt’s that, you say? ...... 363 I hear ’bels ...... 363 RF Mathematics ...... 365 Calculating decibels ...... 365 Calculating path loss ...... 367 Calculating antenna length ...... 367 Calculating coaxial cable losses ...... 368 Calculating the Fresnel zone ...... 368 Calculating the measurements for a home-grown antenna ...... 370
Index...... 371 02_575252 intro.qxd 9/2/04 3:51 PM Page 1
Introduction
ecently, a very knowledgeable speaker at a presentation for a wireless Rvendor talked about wireless as ubiquitous. We would have to disagree. Wireless is widespread, but it is not everywhere. But it is rapidly becoming ubiquitous.
In about 1990, cell phone users carried around a phone that looked and felt like a World War II walkie-talkie. You didn’t casually whip that baby out and start a conversation. At that time, you either had a deep wallet, a big ego, or a compelling need to talk to your mother. Now, depending on where you live in the world, the cell phone provides better quality at a lower cost — and in a much smaller form factor.
In about 1994, Wireless Local Area Network (WLAN) equipment manufacturers sold gear that was comparable to the wireless phone market. The devices were large and very expensive and provided poor bandwidth. You had to have a compelling reason to spend the money on the low bandwidth. But that has changed. In 2004, you can buy a reasonably priced laptop with onboard sup- port for 802.11b and Bluetooth. You can add a fairly inexpensive 802.11a and g PC Card and easily connect wirelessly and, if you have a Centrino-based system or Microsoft Windows XP, somewhat seamlessly. The WLAN market of today is analogous to the Ethernet market of the mid 1980s. In those years, solutions were proprietary, and standards were being approved. Companies were jockeying for position. Now, you would have difficulty finding a desktop or laptop computer that does not come with Ethernet support. When we look back from the future, we will see some parallels between 802.3 and 802.11 development.
Telephone companies have wrestled with the issue of the “last mile” for a while. But forget the last mile; Bluetooth and IrDA provide the last foot. Mice, keyboards, phones, PDAs, and other devices support Bluetooth for wire replacement. When you have a Bluetooth-enabled printer, you no longer need to hook up to the network to print one page or a contact.
Vendors are trying to get along with each other to develop standards so that one day we can walk around with a phone, PDA, or laptop and connect to any network, anywhere, anytime. 02_575252 intro.qxd 9/2/04 3:51 PM Page 2
2 Wireless Networks For Dummies
We wrote this book for those of you who want to release your company from its bondage. If you want to unfetter your clients so that they can access their e-mail before getting on the red-eye to New York or Toronto, this book is for you. If your desktop looks like spaghetti junction and you want to rid yourself of all those wires, this book is for you. If you want to provide up-to-the-minute stock quotes to the Chair of your company while she sits in the boardroom, this book is for you. If you have a small to medium enterprise (SME) or busi- ness (SMB) or a small office/home office (SOHO) and don’t want to rewire (or pay someone to rewire) your office, this book is for you. If you have wire- less at home and want to learn about features that you can expect for home gear, this book is for you.
About This Book Mark Twain once wrote, “Writing is easy. All you have to do is cross out the wrong words.” So we have done the easy part for you. We crossed out all the wrong words and came up with this book. What are left are the words that will help you plan for, install, acquire, protect, manage, and administer wireless networks from personal area to wide area.
We have started your journey by providing information on