1.3.1a Networks — OCR J277

What is a Network?

A computer network is two or more computers or devices connected together to share resources, data, and services. Networks allow sharing of files, printers, internet connections, and applications.

Networks can be categorised by their geographical size:

LAN — Local Area Network

A LAN covers a small geographical area — typically a single building, office, school, or home.

Property	Detail
Coverage area	Small: single building / site / home
Ownership	Usually owned and managed by the organisation using it
Connection media	Ethernet cable (wired) or Wi-Fi (wireless)
Speed	Typically fast — 100 Mbps to 10 Gbps
Examples	School network, office network, home Wi-Fi

In a LAN, devices are connected using Ethernet cables or wireless access points (WAPs). The infrastructure (cables, switches, routers) is usually owned by the organisation.

WAN — Wide Area Network

A WAN covers a large geographical area — spanning cities, countries, or even the entire world. The Internet is the largest WAN in existence.

Property	Detail
Coverage area	Large: cities, countries, worldwide
Ownership	Infrastructure owned by telecom companies (BT, Virgin, etc.)
Connection media	Telephone lines, fibre optic cables, satellite links, microwave
Speed	Typically slower than LAN; varies greatly
Examples	The Internet, a company's network across multiple offices worldwide

Organisations use leased lines (dedicated connections rented from telecoms companies) or public internet connections to link their LANs across a WAN.

PAN — Personal Area Network

A PAN is a very small network — typically within a few metres of a person. It connects personal devices together.

Property	Detail
Coverage area	Very small: a few metres
Technology	Bluetooth, NFC, USB, infrared
Examples	Smartphone to wireless headphones, smartwatch to phone, laptop to Bluetooth keyboard

Comparing LAN, WAN and PAN

Feature	PAN	LAN	WAN
Coverage	~metres	Building/site	Cities/countries/worldwide
Speed	Low–medium	High	Variable (often lower)
Infrastructure owner	Individual	Organisation	Telecoms company
Technology	Bluetooth, NFC	Ethernet, Wi-Fi	Fibre, leased lines, satellite
Example	Bluetooth headphones	School network	The Internet

Advantages of Networking

Shared resources: printers, scanners, storage can be shared by many users
Shared internet connection: one broadband connection shared across many devices
Centralised data storage: files stored on a server accessible from any device
Communication: email, messaging, video calls
Centralised security & updates: easier to apply updates and manage security

Disadvantages of Networking

Security risks: networks are a target for hackers and malware
Cost of setup: cables, switches, routers, server hardware
Dependence on network: if network fails, users cannot access shared resources
Data can be intercepted: sensitive data at risk if not encrypted

Exam tip: Know the three types — LAN, WAN, PAN — and their key features: coverage area, typical technology, ownership. The Internet is a WAN. A school network is a LAN. Bluetooth headphones = PAN. OCR questions often ask you to identify network type from a scenario and justify your answer — make sure you explain WHY (e.g. "it covers a small area — one building — so it is a LAN").

⚠️ Common Mistakes

Saying "WAN is faster than LAN" — LANs are typically faster; WANs are larger but often slower
Saying "the internet is a LAN" — the internet is the world's largest WAN
Confusing PAN with LAN — PANs are personal (few metres, Bluetooth); LANs are building-scale
Saying organisations own WAN infrastructure — telecom companies do
Not justifying answers — "it is a LAN because it covers one school building" scores more marks than just "LAN"

✅ Notes completed!

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What's in this video

• What is a computer network and why networks exist
• LAN: coverage, ownership, Ethernet, Wi-Fi, school example
• WAN: coverage, telecoms ownership, the Internet
• PAN: Bluetooth, personal devices; advantages and disadvantages of networking

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Worksheet — 1.3.1a Types of Networks

8 questions · 19 marks

Q1What is a computer network?[1]

✅ Mark scheme

Two or more computers/devices connected together to share data, resources, and services [1].

Q2What does LAN stand for? Describe what it is.[2]

✅ Mark scheme

Local Area Network [1]; a network that covers a small geographical area — typically a single building or site [1].

Q3What does WAN stand for? Give one example of a WAN.[2]

✅ Mark scheme

Wide Area Network [1]; the Internet / a bank's network connecting branches across multiple countries [1].

Q4A student pairs their phone with Bluetooth headphones. What type of network is this? Justify your answer.[2]

✅ Mark scheme

PAN (Personal Area Network) [1]; it connects personal devices over a very short range (a few metres) using Bluetooth [1].

Q5State two differences between a LAN and a WAN.[4]

✅ Mark scheme

LAN covers a small area (building); WAN covers a large area (cities/countries) [1+1]; LAN infrastructure is owned by the organisation; WAN infrastructure is owned by telecoms companies [1+1]. (Or: LAN typically faster than WAN [1+1] with explanation.)

Q6State two advantages of connecting computers in a network.[2]

✅ Mark scheme

Any two: shared resources (printers, storage) [1]; shared internet connection [1]; centralised data storage [1]; communication via email/messaging [1]; centralised software updates/security management [1].

Q7State two disadvantages of networking.[2]

✅ Mark scheme

Any two: security risks — hacking/malware [1]; cost of hardware/setup [1]; reliance on the network — if it fails, shared resources unavailable [1]; data can be intercepted [1].

Q8A hospital connects computers in its reception, wards and operating rooms — all within one large building. A separate branch 200 miles away connects via the Internet. Identify the type of network used (a) within the building and (b) between the two sites. Justify each answer.[4]

✅ Mark scheme

(a) LAN [1] — covers a single building/site [1]; (b) WAN [1] — connects over a large geographical distance (200 miles); uses Internet infrastructure owned by telecoms companies [1].

out of 19 — self-mark above

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Complete!

Term	Definition

What is a Network?

LAN — Local Area Network

WAN — Wide Area Network

PAN — Personal Area Network

Comparing LAN, WAN and PAN

Advantages of Networking

Disadvantages of Networking

What's in this video

Worksheet — 1.3.1a Types of Networks

Mini Test — 1.3.1a Networks