This topic summary covers Knowledge Organiser: LAN and WAN within LAN and WAN for GCSE Computer Science. Revise LAN and WAN in 3.5 Fundamentals of Computer Networks for GCSE Computer Science with 18 exam-style questions and 16 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 11 of 11 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Knowledge Organiser: LAN and WAN
Key Terms
- LAN: Local Area Network — covers a small geographic area (single building/campus)
- WAN: Wide Area Network — covers large geographic areas (cities, countries, global)
- Network: Two or more devices connected to share resources and communicate
- Router: Device that connects a LAN to the Internet (WAN)
- Switch: Device that connects devices within a LAN
Must-Know Facts
- LAN: small area (one building), privately owned, fast (1–10 Gbps), low cost
- WAN: large area (cities/countries), third-party telecoms infrastructure, slower, expensive monthly fees
- The Internet is the largest example of a WAN
- LAN infrastructure (cables, switches, WiFi) owned by the organisation
- WAN infrastructure owned by telecoms companies (BT, Virgin, etc.)
- LAN is more secure — physical access needed to connect
- ALWAYS give BOTH size AND ownership when comparing LAN and WAN
Key Concepts
- Why LAN is faster: Short cable distances mean less signal degradation and delay
- Why WAN costs more: Organisation must pay telecoms companies monthly rental fees for infrastructure
- LAN + WAN together: Most organisations have a private LAN that connects to the Internet via a WAN link (router)
- Exam answer structure: State size difference AND ownership difference for full marks
Common Mistakes
- Only giving one difference between LAN and WAN: Exam questions award marks for both geographic size AND ownership — a LAN covers a small area AND is privately owned; a WAN covers a large area AND uses third-party infrastructure
- Saying the Internet is a WAN: The Internet is the largest example of a WAN, but not all WANs are the Internet — a company linking two offices in different cities uses a private WAN
- Confusing routers and switches: A switch connects devices within a LAN; a router connects different networks together (e.g. LAN to the Internet)
- Saying LANs cannot be wireless: A LAN can use either wired (Ethernet) or wireless (Wi-Fi) connections — the defining feature is geographic size, not the medium used
Practice questions for LAN and WAN
What does LAN stand for?
State three differences between a LAN and a WAN. [3 marks]