CWNA Certified Wireless Network Administrator Study Guide (6^th Ed.)
Exam CWNA-108
Sybex Study Guide Series

The #1 selling Wi-Fi networking reference guide in the world 

The CWNA: Certified Wireless Network Administrator Study Guide is the ultimate preparation resource for the CWNA exam. Fully updated to align with the latest version of the exam, this book features expert coverage of all exam objectives to help you pass the exam. But passing the exam is just a first step. For over 16 years, the CWNA Study Guide has helped individuals jump-start their wireless networking careers. Wireless networking professionals across the globe use this book as their workplace reference guide for enterprise Wi-Fi technology. 

Owning this book provides you with a foundation of knowledge for important Wi-Fi networking topics, including: 

• Radio frequency (RF) fundamentals
• 802.11 MAC and medium access
• Wireless LAN topologies and architecture
• WLAN design, troubleshooting and validation
• Wi-Fi networking security 

The book authors have over 40 years of combined Wi-Fi networking expertise and provide real-world insights that you can leverage in your wireless networking career. Each of the book?s 20 chapters breaks down complex topics into easy to understand nuggets of useful information. Each chapter has review questions that help you gauge your progress along the way. Additionally, hands-on exercises allow you to practice applying CWNA concepts to real-world scenarios. You also get a year of free access to the Sybex online interactive learning environment, which features additional resources and study aids, including bonus practice exam questions. 

The CWNA certification is a de facto standard for anyone working with wireless technology. It shows employers that you have demonstrated competence in critical areas, and have the knowledge and skills to perform essential duties that keep their wireless networks functioning and safe. The CWNA: Certified Wireless Network Administrator Study Guide gives you everything you need to pass the exam with flying colors. 

Foreword xxxv

Introduction xxxvii

Assessment Test lvi

Chapter 1 Overview of Wireless Standards, Organizations, and Fundamentals 1

History of Wireless Local Area Networks 3

Standards Organizations 5

Institute of Electrical and Electronics Engineers 8

Core, Distribution, and Access 22

Communications Fundamentals 24

Summary 33

Exam Essentials 33

Review Questions 34

Chapter 2 IEEE 802.11 Standard and Amendments 39

Original IEEE 802.11 Standard 42

IEEE 802.11-2020 Ratified Amendments 44

IEEE 802.11 Draft Amendments 63

Defunct Amendments 66

IEEE Task Group m 68

Summary 69

Exam Essentials 69

Review Questions 70

Chapter 3 Radio Frequency Fundamentals 75

What Is a Radio Frequency Signal? 77

Radio Frequency Characteristics 78

Radio Frequency Behaviors 87

Summary 103

Exam Essentials 103

Review Questions 104

Chapter 4 Radio Frequency Components, Measurements, and Mathematics 109

Components of RF Communications 112

Units of Power and Comparison 115

RF Mathematics 123

Noise Floor 130

Signal-to-Noise Ratio 130

Received Signal Strength Indicator 131

Link Budget 135

Summary 140

Exam Essentials 142

Review Questions 143

Chapter 5 Radio Frequency Signal and Antenna Concepts 147

Azimuth and Elevation Charts (Antenna Radiation Envelopes) 150

Interpreting Polar Charts 152

Beamwidth 155

Antenna Types 157

Visual Line of Sight 169

RF Line of Sight 169

Fresnel Zone 170

Earth Bulge 174

Antenna Polarization 175

Antenna Diversity 176

Multiple-Input, Multiple-Output 177

Antenna Connection and Installation 179

Antenna Accessories 187

Regulatory Compliance 192

Summary 194

Exam Essentials 194

Review Questions 195

Chapter 6 Wireless Networks and Spread Spectrum Technologies 199

Throughput vs. Bandwidth 201

Narrowband and Spread Spectrum 202

Frequency-Hopping Spread Spectrum 205

Direct-Sequence Spread Spectrum 208

Orthogonal Frequency-Division Multiplexing 211

Industrial, Scientific, and Medical Bands 218

5 GHz Unlicensed National Information Infrastructure Bands 220

60 GHz for Wi-Fi 223

Below 1 GHz 224

2.4 GHz Channels 224

5 GHz Channels 227

6 GHz Channels 232

Summary 239

Exam Essentials 239

Review Questions 240

Chapter 7 Wireless LAN Topologies 245

Wireless Networking Topologies 247

802.11 Stations 251

802.11 Service Sets 255

802.11 Configuration Modes 267

Summary 269

Exam Essentials 269

Review Questions 271

Chapter 8 802.11 Medium Access 275

CSMA/CA vs. CSMA/CD 276

Collision Detection 277

Distributed Coordination Function 278

Hybrid Coordination Function 286

Wi-Fi Multimedia 288

Airtime Fairness 290

Summary 292

Exam Essentials 292

Review Questions 293

Chapter 9 802.11 MAC 297

Packets, Frames, and Bits 299

Data-Link Layer 300

Physical Layer 301

802.11 and 802.3 Interoperability 302

802.11 MAC Header 303

802.11 Frame Body 315

802.11 Trailer 316

802.11 State Machine 317

Management Frames 318

Control Frames 333

Data Frames 341

Power Management 344

Summary 350

Exam Essentials 350

Review Questions 352

Chapter 10 MIMO Technology: HT and VHT 357

MIMO 360

Multi-User MIMO 371

Channels 376

Guard Interval 382

256-QAM Modulation 384

802.11n/ac PPDUs 388

802.11n/ac MAC 390

HT/VHT Protection Mechanisms 399

Wi-Fi Alliance Certification 400

Summary 403

Exam Essentials 403

Review Questions 405

Chapter 11 WLAN Architecture 409

WLAN Client Devices 411

Management, Control, and Data Planes 421

WLAN Architecture 423

Specialty WLAN Infrastructure 437

Cloud Networking 445

Application Programming Interface 448

Infrastructure Management 451

Summary 456

Exam Essentials 457

Review Questions 458

Chapter 12 Power over Ethernet (PoE) 463

History of PoE 464

PoE Devices 467

Planning and Deploying PoE 484

Summary 490

Exam Essentials 491

Review Questions 492

Chapter 13 WLAN Design Concepts 497

WLAN Coverage Design 499

Roaming Design 505

Channel Design 512

Capacity Design 534

Voice vs. Data 546

Dual 5 GHz and Software-Defined Radios 548

6 GHz WLAN Design 551

Physical Environment 557

Antennas 558

Outdoor Design 562

Summary 563

Exam Essentials 564

Review Questions 565

Chapter 14 Site Survey and Validation 569

WLAN Site Survey and Design Interview 572

Vertical Market Considerations 582

Legacy AP-on-a-Stick Survey 585

Hybrid Survey 595

Validation Survey 599

Site Survey Tools 604

Documents and Reports 609

Summary 614

Exam Essentials 615

Review Questions 616

Chapter 15 WLAN Troubleshooting 621

Five Tenets of WLAN Troubleshooting 623

Layer 1 Troubleshooting 629

Layer 2 Troubleshooting 636

Security Troubleshooting 648

Roaming Troubleshooting 661

Channel Utilization 665

Layers 3–7 Troubleshooting 667

WLAN Troubleshooting Tools 671

Summary 679

Exam Essentials 679

Review Questions 680

Chapter 16 Wireless Attacks, Intrusion Monitoring, and Policy 687

Wireless Attacks 688

Intrusion Monitoring 706

Wireless Security Policies 712

Summary 716

Exam Essentials 717

Review Questions 718

Chapter 17 802.11 Network Security Architecture 723

802.11 Security Basics 725

Legacy 802.11 Security 729

Robust Security 736

Management Frame Protection 757

WPA 2 757

WPA 3 758

Enhanced Open 761

6 GHz Wi-Fi Security 762

Traffic Segmentation 763

VPN Wireless Security 766

Summary 770

Exam Essentials 770

Review Questions 772

Chapter 18 Bring Your Own Device (BYOD) and Guest Access 777

Mobile Device Management 780

Company-Issued Devices vs. Personal Devices 781

Self-Service Device Onboarding for Employees 795

Guest WLAN Access 798

Hotspot 2.0 and Passpoint 811

Network Access Control 816

Summary 824

Exam Essentials 825

Review Questions 826

Chapter 19 802.11ax: High Efficiency (HE) 831

802.11ax = Wi-Fi 6 833

Wi-Fi Traffic Congestion 834

HE Overview 836

Multi-User 837

OFDMA 838

MU-MIMO 851

BSS Color and Spatial Reuse 855

Target Wake Time 861

Additional 802.11ax PHY and MAC Capabilities 862

Wi-Fi 6 Key Questions 867

Wi-Fi CERTIFIED 6 873

Summary 874

Review Questions 875

Chapter 20 WLAN Deployment and Vertical Markets 879

Deployment Considerations for Commonly Supported WLAN Applications and Devices 881

Corporate Data Access and End-User Mobility 885

Network Extension to Remote Areas 886

Bridging: Building-to-Building Connectivity 887

Wireless ISP: Last-Mile Data Delivery 888

Small Office/Home Office 888

Temporary Office Networking 889

Branch Offices 890

Teleworker Wi-Fi 890

Educational/Classroom Use 891

Industrial: Warehousing and Manufacturing 892

Retail 892

Healthcare 894

Municipal Networks 895

Hotspots: Public Network Access 895

Stadium Networks 897

Transportation Networks 897

Law Enforcement Networks 898

First-Responder Networks 899

Managed Service Providers 900

Fixed Mobile Convergence 900

WLAN and Health 901

Internet of Things 901

WLAN Vendors 902

Summary 904

Exam Essentials 904

Review Questions 905

Appendix A Answers to Review Questions 909

Chapter 1: Overview of Wireless Standards, Organizations, and Fundamentals 910

Chapter 2: IEEE 802.11 Standard and Amendments 911

Chapter 3: Radio Frequency Fundamentals 914

Chapter 4: Radio Frequency Components, Measurements, and Mathematics 915

Chapter 5: Radio Frequency Signal and Antenna Concepts 918

Chapter 6: Wireless Networks and Spread Spectrum Technologies 919

Chapter 7: Wireless LAN Topologies 922

Chapter 8: 802.11 Medium Access 924

Chapter 9: 802.11 Mac 926

Chapter 10: MIMO Technology: HT and VHT 929

Chapter 11: WLAN Architecture 932

Chapter 12: Power over Ethernet (PoE) 934

Chapter 13: WLAN Design Concepts 937

Chapter 14: Site Survey and Validation 940

Chapter 15: WLAN Troubleshooting 943

Chapter 16: Wireless Attacks, Intrusion Monitoring, and Policy 946

Chapter 17: 802.11 Network Security Architecture 948

Chapter 18: Bring Your Own Device (BYOD) and Guest Access 951

Chapter 19: 802.11ax: High Efficiency (HE) 954

Chapter 20: WLAN Deployment and Vertical Markets 957

Appendix B Abbreviations and Acronyms 961

Certifications 962

Organizations and Regulations 962

Measurements 963

Technical Terms 964

Index 981

DAVID D. COLEMAN, CWNE #4, David D. Coleman, CWNE #4, is a technology evangelist and public speaker who specializes in Wi-Fi and cloud technologies. David is also Director of Product Marketing for Extreme Networks. He is the author of numerous books, white papers and videos about Wi-Fi technology. DAVID A. WESTCOTT, CWNE #7, is an independent consultant and WLAN technical trainer of thirty years. He provides vendor and custom wireless training to government agencies, corporations and universities around the world.