Wireless Networking

This lesson covers wireless networking technologies, including WiFi standards, Bluetooth, frequency bands, SSIDs, WPA2/WPA3, and security considerations. These topics are part of the OCR H446 specification.

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What is Wireless Networking?

Wireless networking uses radio waves (or infrared) to transmit data between devices, eliminating the need for physical cables. The most common wireless networking technology is WiFi (Wireless Fidelity), based on the IEEE 802.11 standards.

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WiFi Standards (IEEE 802.11)

The IEEE 802.11 family defines wireless networking standards. Each generation improves speed, range, and capacity.

Standard	Name	Max Speed	Frequency	Year
802.11a	—	54 Mbps	5 GHz	1999
802.11b	—	11 Mbps	2.4 GHz	1999
802.11g	—	54 Mbps	2.4 GHz	2003
802.11n	WiFi 4	600 Mbps	2.4 / 5 GHz	2009
802.11ac	WiFi 5	3.5 Gbps	5 GHz	2013
802.11ax	WiFi 6	9.6 Gbps	2.4 / 5 / 6 GHz	2020

Key Trends

• Speed has increased dramatically with each generation.
• Dual-band (2.4 GHz and 5 GHz) became standard from 802.11n onwards.
• WiFi 6 introduced better performance in crowded environments (OFDMA, MU-MIMO).

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Frequency Bands

Wireless networks operate on specific radio frequency bands.

2.4 GHz Band

Feature	Detail
Range	Longer range (better at penetrating walls)
Speed	Lower maximum speed
Channels	14 channels (only 3 non-overlapping: 1, 6, 11)
Interference	High — shared with Bluetooth, microwaves, baby monitors, other devices
Congestion	More congested in dense environments

5 GHz Band

Feature	Detail
Range	Shorter range (more absorbed by walls)
Speed	Higher maximum speed
Channels	Many more non-overlapping channels (over 20)
Interference	Lower — fewer competing devices
Congestion	Less congested

Choosing a Frequency Band

Scenario	Best Band	Reason
Large house, walls between rooms	2.4 GHz	Better wall penetration
Close to the router, need high speed	5 GHz	Faster, less interference
Crowded apartment building	5 GHz	More channels, less congestion
IoT devices (smart home)	2.4 GHz	Longer range, lower power

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SSID (Service Set Identifier)

The SSID is the name of a wireless network that devices see when scanning for available WiFi networks.

Feature	Detail
Purpose	Identifies the network so users can select it
Broadcast	By default, the SSID is broadcast so it appears in the list of available networks
Hidden SSID	The SSID can be hidden (not broadcast), requiring users to type it manually
Security note	Hiding the SSID is NOT strong security — the SSID can still be discovered using network analysis tools

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Wireless Security

Why Wireless Security is Important

Wireless signals travel through the air and can be intercepted by anyone within range. Without encryption, all data (including passwords and personal information) can be captured by an attacker with a simple WiFi adapter.

WEP (Wired Equivalent Privacy) — Obsolete

Feature	Detail
Status	Obsolete — seriously flawed
Encryption	RC4 stream cipher with fixed keys
Key length	40 or 104 bits
Vulnerability	Can be cracked in minutes using freely available tools
Should be used	Never — if this is your only option, upgrade your router

WPA (WiFi Protected Access)

Feature	Detail
Improvement over	WEP
Encryption	TKIP (Temporal Key Integrity Protocol)
Key management	Dynamic keys (changed regularly)
Status	Better than WEP but still vulnerable to some attacks

WPA2