Cambridge IGCSE ICT 0417 – Networks: Uses of Wi‑Fi and Bluetooth
4 Networks and the Effects of Using Them
Objective
Know and understand the uses of Wi‑Fi and Bluetooth.
What is Wi‑Fi?
Wi‑Fi (Wireless Fidelity) is a family of wireless networking technologies based on the IEEE 802.11 standards. It allows devices to connect to a local area network (LAN) and the Internet without physical cables.
Typical frequency bands: 2.4 GHz and 5 GHz (and newer 6 GHz for Wi‑Fi 6E).
Typical range: up to 30 m indoors, up to 100 m outdoors, depending on the standard and environment.
Common standards: 802.11b/g/n/ac/ax (Wi‑Fi 4‑6).
Provides high data‑transfer rates, from 11 Mbps (802.11b) to several Gbps (802.11ax).
What is Bluetooth?
Bluetooth is a short‑range wireless technology designed for low‑power, point‑to‑point or point‑to‑multipoint communication between devices. It follows the IEEE 802.15.1 standard.
Frequency band: 2.4 GHz (ISM band).
Typical range: Class 2 devices up to 10 m; Class 1 devices up to 100 m.
Versions: Bluetooth 1.0 – 5.4, each improving speed, range, and power consumption.
Data‑transfer rates: from 1 Mbps (Bluetooth 1.2) to 2 Mbps (Bluetooth 5.0) for classic Bluetooth; up to 50 Mbps for Bluetooth 5.2 LE (Low Energy) in high‑speed mode.
Comparison of Wi‑Fi and Bluetooth
Feature
Wi‑Fi
Bluetooth
Primary purpose
Network connectivity (Internet, LAN)
Device‑to‑device communication
Typical range
10 m – 100 m (depends on standard)
1 m – 100 m (class dependent)
Data‑transfer speed
Up to several Gbps (Wi‑Fi 6/6E)
Up to 2 Mbps (classic) / 50 Mbps (LE high‑speed)
Power consumption
Moderate to high
Low (especially Bluetooth LE)
Typical devices
Laptops, smartphones, tablets, smart T \cdot s, routers
Headsets, keyboards, mice, fitness trackers, car audio
Network topology
Infrastructure (AP/Router) or ad‑hoc
Piconet (up to 8 active devices) and scatternet
Advantages and Disadvantages
Wi‑Fi
Advantages: High speed, supports many users, can cover whole homes or offices, enables Internet access.
Disadvantages: Higher power use, more susceptible to interference from other 2.4 GHz devices, requires a router or access point.
Disadvantages: Limited range and speed, can support only a few simultaneous connections, less suitable for large data transfers.
Practical Applications in Everyday Life
Connecting a laptop to a wireless router for Internet access (Wi‑Fi).
Streaming music from a smartphone to a Bluetooth speaker.
Using a Bluetooth keyboard and mouse with a tablet.
Pairing wireless headphones to a laptop for video conferencing.
Transferring photos between smartphones via Bluetooth.
Setting up a home automation hub that communicates with sensors via Bluetooth Low Energy.
Security Considerations
Wi‑Fi: Use WPA3 encryption, change default router passwords, hide SSID if not needed, enable guest networks for visitors.
Bluetooth: Keep device visibility off when not pairing, use “Just Works” pairing only in trusted environments, apply firmware updates to fix known vulnerabilities.
Suggested diagram: A schematic showing a Wi‑Fi router connecting multiple devices (laptop, tablet, smart TV) and a Bluetooth piconet linking a smartphone, headset, and fitness tracker.