Wireless Networks and IEEE 802.11 Standards

Introduction

• Wireless Networks: Ubiquitous connectivity; requires extensive behind-the-scenes work.
• IEEE: The Institute of Electrical and Electronics Engineers is key to setting standards.

IEEE 802.11 Committee

• Focus: Creating worldwide standards for wireless networking.
• Naming Conventions:
  • Numbers and letters, e.g., 802.11ac, 802.11ax, 802.11be.
  • User-friendly names: Wi-Fi 5 (802.11ac), Wi-Fi 6 (802.11ax), Wi-Fi 6e, Wi-Fi 7 (802.11be).
  • Future releases will incrementally increase: Wi-Fi 8, 9, etc.

Frequencies and Channels

• Frequency Ranges: Commonly use 2.4 GHz, 5 GHz, and 6 GHz.
• Channels: Grouped frequencies for easier identification.
  • Example: Channel 6 at 2.4 GHz centered on 2.437 GHz.
• Wireless Bandwidth: Different sizes such as 20 MHz, 40 MHz, 80 MHz, and 160 MHz.

Spectrum Utilization

• 2.4 GHz Spectrum: 3 non-overlapping channels with 20 MHz bandwidth.
• 5 GHz Spectrum: More frequencies; variable bandwidths (20 MHz to 160 MHz).
• 6 GHz Spectrum: More frequencies for more options, reduces conflict.

Frequency Selection and Band Steering

• Frequency Selection: Environmental and device-dependent.
• Band Steering: Feature for optimal frequency use.
  • Example: Admin can configure access point to prefer 5 GHz over 2.4 GHz.

Regulatory Considerations

• Global Coordination: Each country manages its own frequencies.
  • Example: FCC in the United States.
• Interoperability: Standards like 802.11h ensure networks work together.
• International Telecommunications Union (ITU): Publishes global guidelines.

Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC)

• DFS: Automatically selects non-conflicting frequencies.
• TPC: Access point controls client power levels to optimize communication.
• Benefits: Reduces manual configuration; adapts to changing environments.