2.3 Comparing and Contrasting Protocols for Wireless Networking

COMPTIA A+ CORE 1 - DOMAIN 2

Cyber Wizard

wifi signal on metallic panel
wifi signal on metallic panel

This article explores the differences between various wireless networking protocols, including frequencies, channels, Wi-Fi standards, Bluetooth, NFC, RFID, and long-range fixed wireless technologies, as required for the CompTIA A+ exam.

CompTIA A+ Exam Domain: Domain 2.3 - Compare and contrast protocols for wireless networking.

Wireless Frequencies

Wireless networks operate on different frequency bands, each with unique characteristics affecting speed, range, and interference.

2.4GHz Frequency

  • Longer range, better penetration through walls.

  • More susceptible to interference from household devices (e.g., microwaves, Bluetooth, cordless phones).

  • Supports lower data speeds compared to higher frequencies.

  • Used in 802.11b/g/n Wi-Fi standards.

5GHz Frequency

  • Higher speeds due to wider bandwidth availability.

  • Shorter range compared to 2.4GHz; does not penetrate obstacles as well.

  • Less interference, making it ideal for high-bandwidth applications.

  • Used in 802.11a/n/ac/ax (Wi-Fi 6) standards.

Wireless Channels

Wireless frequencies are divided into multiple channels to minimize interference and optimize network performance.

Channel Regulations

  • 2.4GHz band has 11-14 channels, but only 3 non-overlapping (1, 6, 11 in the U.S.).

  • 5GHz band has more available channels and wider channel widths (20MHz, 40MHz, 80MHz, 160MHz).

  • Regulatory bodies (FCC, ETSI) control frequency allocation and transmission power limits.

2.4GHz vs. 5GHz Channel Usage

  • 2.4GHz – More crowded, prone to interference.

  • 5GHz – More available channels, supports higher speeds.

Bluetooth

  • Short-range wireless technology operating in the 2.4GHz band.

  • Used for device pairing, audio streaming, input devices, and file transfers.

  • Versions:

    • Bluetooth 4.0 – Introduced Low Energy (BLE) for power efficiency.

    • Bluetooth 5.0+ – Increased range, speed, and bandwidth for IoT applications.

Wi-Fi Standards (IEEE 802.11)

Wi-Fi standards define wireless networking capabilities, speeds, and frequencies.

802.11a (1999)

  • 5GHz band, 54 Mbps, short range.

  • Less interference but lower adoption.

802.11b (1999)

  • 2.4GHz band, 11 Mbps, longer range.

  • Prone to interference.

802.11g (2003)

  • 2.4GHz band, 54 Mbps.

  • Backward-compatible with 802.11b.

802.11n (Wi-Fi 4) (2009)

  • 2.4GHz and 5GHz bands, up to 600 Mbps.

  • Introduced MIMO (Multiple Input, Multiple Output) for better throughput.

802.11ac (Wi-Fi 5) (2014)

  • 5GHz band, up to 6.9 Gbps.

  • Supports MU-MIMO (Multi-User MIMO) for better multi-device efficiency.

  • Wider channels (up to 160MHz) for increased data transfer rates.

802.11ax (Wi-Fi 6) (2019)

  • 2.4GHz and 5GHz bands, up to 9.6 Gbps.

  • Supports OFDMA (Orthogonal Frequency-Division Multiple Access) for more efficient spectrum use.

  • Better performance in high-density environments (stadiums, offices).

  • Introduces Target Wake Time (TWT) to improve battery life in IoT devices.

Long-Range Fixed Wireless

Used for broadband access in remote areas without traditional wired infrastructure.

Licensed vs. Unlicensed Bands

  • Licensed: Requires government approval, less interference (used by ISPs, cellular towers).

  • Unlicensed: Open to public use, more interference (Wi-Fi, home networks).

Power Considerations

  • Higher power increases range but requires regulatory approval.

  • Limited by government-imposed EIRP (Effective Isotropic Radiated Power) restrictions.

Regulatory Requirements for Wireless Power

  • Compliance with FCC, ITU, and regional authorities is mandatory.

  • Power limits prevent excessive interference with other networks.

Near-Field Communication (NFC)

  • Short-range wireless technology (up to 4 cm).

  • Used for contactless payments, keyless entry, and device pairing.

  • Operates at 13.56 MHz.

  • Requires close-proximity authentication for secure transactions.

Radio-Frequency Identification (RFID)

  • Uses radio waves for tracking, inventory management, and access control.

  • Components:

    • RFID Tags – Passive (no power source) or active (battery-powered).

    • RFID Reader – Captures tag data for processing.

  • Operates on low-frequency (LF), high-frequency (HF), or ultra-high-frequency (UHF) bands.

Final Thoughts

Understanding wireless networking protocols is essential for IT professionals. The CompTIA A+ exam tests knowledge of different wireless standards, their frequencies, channels, and use cases. Mastering these concepts will help in configuring, troubleshooting, and optimizing wireless networks effectively.