| Acknowledgments | xv |
| Introduction | xvii |
1 | The Wireless Revolution | 1 |
| Why Wireless Networks Are Cool | 1 |
| Mobility | 2 |
| Flexibility | 2 |
| Cost Savings | 2 |
| Scalability | 3 |
| Wireless Technology Overview | 3 |
| Frequency | 4 |
| Spectrum | 4 |
| Current and Future Wireless Networking Technologies | 5 |
| IEEE 802.11 | 5 |
| Bluetooth | 7 |
| HomeRF | 8 |
| HiperLAN | 8 |
| How Wi-Fi Fits In | 8 |
2 | IEEE 802.11 In Depth | 11 |
| Parts of a Wi-Fi Network | 11 |
| The OSI Reference Model | 12 |
| Layers and Sublayers | 13 |
| The Physical (PHY) Layer | 14 |
| The Media Access Control (MAC) Layer | 15 |
| Frequency Spectrum and Wi-Fi | 16 |
| 802.11b and DSSS | 17 |
| 802.11a and OFDM | 17 |
| FHSS | 18 |
| Network Topology | 18 |
| Extended Service Sets | 19 |
| Supporting 802.11 Standards | 22 |
3 | Choosing a Wireless Access Point | 23 |
| Do You Need an Access Point? | 23 |
| Is One Access Point Enough? | 25 |
| Access Point Parts | 25 |
| The Radio | 26 |
| Connectivity | 27 |
| Antennas | 29 |
| Box Design | 29 |
| Internet Access, Networking, and Administration | 30 |
| Shared Internet Access | 30 |
| DHCP Server | 30 |
| Firewall | 32 |
| Routing and Bridging | 36 |
| Security | 37 |
| Special Features | 40 |
| Access Point Checklist | 40 |
4 | Network Adapters and Interfaces | 43 |
| Anatomy of a Wi-Fi Network Adapter | 43 |
| Kinds of Network Adapters | 45 |
| PC Cards | 45 |
| PCI and ISA Network Adapters | 46 |
| USB Adapters | 47 |
| Special Network Adapters | 48 |
| NIC Drivers and OS-Compatibility | 49 |
5 | Antennas and Accessories | 51 |
| Antenna Basics | 51 |
| Types of Antennas | 53 |
| Connectors and Cabling | 57 |
| Home-brew Antennas | 58 |
| Choosing Antennas | 58 |
| Bridges and Repeaters | 63 |
| Software | 64 |
6 | Choosing Internet Access | 67 |
| How Wi-Fi Internet Access Works | 67 |
| The Data Link | 68 |
| Hardware and Connections | 69 |
| Nontraditional Setups | 69 |
| Internet Access Choices in Detail | 69 |
| Dial-Up Access | 70 |
| Broadband Options | 71 |
| Cable | 72 |
| DSL | 73 |
| Satellite | 74 |
| Internet Account Features | 75 |
| Account Sharing Issues | 76 |
7 | Setting Up and Configuring Access Points | 79 |
| Planning Your Network | 79 |
| Setting Up an Access Point | 80 |
| Interference | 81 |
| Connectivity Issues | 81 |
| Basic Access Point Setup | 83 |
| Linksys BEFW11S4 Access Point/Router | 83 |
| Connect the Hardware and Configure the Setup Computer | 84 |
| Initial Setup | 85 |
| Advanced Access Point Configuration | 93 |
| Running Your Own Internet Server | 93 |
| Outbound Filtering | 97 |
| Keyword Filtering | 100 |
| Enhanced Security | 101 |
| Routing | 104 |
| Logging and Monitoring | 106 |
8 | Setting Up Computers for Wi-Fi | 109 |
| Wi-Fi Gear and Operating System Compatibility | 110 |
| Windows 2000 and XP | 110 |
| Windows 95, 98, and Me | 111 |
| Linux | 111 |
| Mac OS X | 112 |
| Mac OS 8 and 9 | 112 |
| Installing Adapters and Drivers | 113 |
| A Brief Terminology Reminder | 113 |
| Installing the D-Link Card Holder and Network Adapter Under Windows XP | 114 |
| Installing the Agere/Orinoco USB Adapter Under Windows 2000 | 121 |
| Installing the Agere Orinoco Silver Card Under Red Hat Linux | 124 |
| Enabling Support for a PRISM-2 PC Card Under Linux | 127 |
| Installing the Linksys PC Card Under Mac OS X | 129 |
| Installing the Linksys PC Card Under Mac OS 9 | 131 |
9 | Ad-Hoc Wi-Fi | 135 |
| The Techie Side of Ad-Hoc Wi-Fi | 135 |
| Uses of Ad-Hoc Networks | 137 |
| Drawbacks to Ad-Hoc Networks | 138 |
| Ad-Hoc Network Setup | 138 |
| Set Up an Ad-Hoc Network Under Windows XP | 139 |
| Set Up an Ad-Hoc Network Under Windows 2000 | 143 |
| Set Up an Ad-Hoc Network Under Mac OS X | 145 |
| Set Up an Ad-Hoc Network Under Red Hat Linux 7.3 | 147 |
| Test Your Connection | 147 |
| Using an Internet Gateway with an Ad-Hoc Network | 149 |
| Gateways Step-by-Step | 149 |
| Windows XP Gateway Setup | 150 |
| Windows 2000 Gateway Setup | 151 |
| Mac OS X Gateway Setup | 152 |
10 | Security | 153 |
| Why Security Is Crucial for All Networks | 153 |
| Understanding Wireless Security Issues | 155 |
| How Signals Can Be Tracked in the Air | 156 |
| What Is at Risk? | 156 |
| Assessing Your Risk | 160 |
| How Are You Connected to the Internet? | 162 |
| What Information Is Unsecured? | 163 |
| Who Has Access? | 163 |
| What Security Measures Are in Place? | 164 |
| Wi-Fi Security Methods | 164 |
| WEP | 165 |
| Firewalls | 170 |
| Access Control | 173 |
| Common Sense Hacker-Proofing Techniques | 174 |
| Security Tools | 176 |
| SSH Tunneling | 176 |
| IPsec VPNs | 178 |
| Security Analysis and Cracking Tools | 178 |
| Security and Emerging Wireless Standards | 181 |
| 802.1X | 181 |
| 802.11i | 183 |
11 | Wi-Fi Applications | 185 |
| File Sharing | 185 |
| Think Before You Share | 185 |
| Cross-Platform File Sharing | 187 |
| Printing | 188 |
| Setting Up an Access Point Print Server | 189 |
| Wireless Print Servers | 191 |
| Network Gaming | 192 |
| Streaming Video | 192 |
12 | Building a Better Network | 193 |
| Planning Your Network | 194 |
| Requirements' Gathering | 194 |
| The Site Survey | 198 |
| Network Topology and Design | 200 |
| A Closer Look at Wi-Fi Range | 204 |
| Putting It All Together | 207 |
| Installing the Network | 208 |
13 | Advanced Wireless Settings and Network Analysis | 209 |
| Tuning Access Points | 210 |
| Network Analysis | 212 |
| Packet Analysis | 213 |
| Packet Analysis Software | 214 |
Appendix A | Glossary | 215 |
Appendix B | Wi-Fi Resources | 221 |
| Ad-Hoc and Mesh Networking | 221 |
| Antenna-Related Information | 221 |
| Antenna Equipment | 221 |
| Broadband Connectivity | 222 |
| Community Wireless Projects and Information | 222 |
| Equipment Retailers (APs and Network Adapters) | 222 |
| Equipment Vendors (APs and Network Adapters) | 223 |
| Linux and Wi-Fi | 223 |
| Macintosh and Wi-Fi | 223 |
| Mailing Lists | 224 |
| News, Tutorials, and Reviews | 224 |
| Organizations | 224 |
| Security | 224 |
| Software | 225 |
| Standards, Regulations, and Technology | 225 |
| Windows and Wi-Fi | 225 |
| Index | 227 |