What is the primary difference between a LAN and a WAN regarding ownership?

A LAN is typically owned and managed by a single person or organization, whereas a WAN is often under collective or distributed ownership, utilizing third-party infrastructure.

How does the transmission medium of Fiber Optic differ from Copper?

Fiber Optic uses pulses of light through glass strands, while Copper uses electrical signals. This makes Fiber faster, more secure against interference, and capable of longer distances.

When should a wireless network be chosen over a wired network?

Wireless should be chosen when user mobility is required, when the environment makes cabling difficult (e.g., historic buildings), or when adding new devices needs to be quick and flexible.

What is a common misconception about 'Wireless Speed' compared to 'Wired Speed'?

Many assume wireless is just as fast, but wireless speeds are often lower and fluctuate due to physical obstructions, distance from the access point, and interference from other devices.

Why is it incorrect to say that wireless networks are always cheaper than wired?

While you save on cabling costs, the high-quality Wireless Access Points (WAPs) and the security measures required to protect wireless signals can sometimes make the total cost comparable to wired setups.

What error occurs when students confuse 'Bandwidth' with 'Latency'?

Bandwidth is the maximum amount of data that can be sent per second, while Latency is the time delay for a single data packet to travel from source to destination.

Define a 'Wireless Access Point' (WAP).

A WAP is a piece of networking hardware that allows wireless-capable devices to connect to a wired network using Wi-Fi or related standards.

What is 'Attenuation' in the context of network cabling?

Attenuation is the gradual loss of signal strength as it travels through a medium, which is much more significant in copper cables than in fiber optic cables.

What does the term 'Interference' refer to in wireless networking?

Interference refers to the disruption of a signal caused by other electromagnetic waves (like microwaves or other Wi-Fi networks) or physical barriers like thick walls.

Why is Fiber Optic considered more secure than Copper or Wireless?

Fiber Optic is more secure because it does not emit electromagnetic signals that can be 'sniffed' remotely, and it is extremely difficult to physically tap into the cable without breaking the light path.

Wired & Wireless Networks 2026-exams | AQA GCSE Computer Science

9. Fundamentals of Computer Networks

Wired & Wireless Networks 2026-exams

Summary

This knowledge module explores the fundamental methods of connecting devices within a network, focusing on the physical and electromagnetic mediums used for data transmission. It contrasts the high-speed, secure nature of wired connections like fiber optics with the flexibility and mobility offered by wireless technologies such as Wi-Fi and Bluetooth, while also distinguishing between Local Area Networks (LANs) and Wide Area Networks (WANs).

1. Definition & Core Concepts

Network Connectivity refers to the method by which devices are linked to share resources and data. This is primarily achieved through either physical cabling (wired) or electromagnetic waves (wireless).

A Wired Network uses physical mediums such as copper or fiber-optic cables to establish a direct, stable connection between nodes. These are typically used when high reliability and speed are prioritized over mobility.

A Wireless Network utilizes radio waves, infrared, or microwaves to transmit data through the air. This allows for greater device portability and easier network expansion without the need for structural modifications like drilling holes for cables.

Diagram showing the difference between guided wired transmission (straight line) and unguided wireless transmission (wave pattern).

2. Wired Transmission Media

Fiber Optic Cables: These transmit data as pulses of light through glass or plastic strands. They offer the highest bandwidth and speeds, are immune to electromagnetic interference (EMI), and can span vast distances (cities or countries) without signal degradation.
Copper Cables: Traditionally used for telephony, these transmit data via electrical signals. While cost-effective for short distances, they suffer from attenuation (signal weakening over distance) and are susceptible to external interference.
Ethernet: This is the standard protocol and cabling system (often using twisted-pair copper) for connecting devices in a local area network, providing a balance of cost and performance for office or home environments.

3. Wireless Technologies

Wi-Fi (Wireless Fidelity): The most common standard for wireless LANs, using radio waves to connect devices to a central Wireless Access Point (WAP). It provides high-speed data transfer within a limited range (typically up to 90 meters).
Bluetooth: A short-range wireless technology designed for Personal Area Networks (PANs). It is ideal for connecting peripheral devices like headphones or keyboards to a primary device over very short distances.
Signal Constraints: Wireless signals are affected by physical obstructions (walls, furniture) and interference from other electronic devices, which can reduce the effective range and data throughput.

4. Network Scale: LAN vs. WAN

5. Key Distinctions

6. Exam Strategy & Tips