LAN, WAN, topologies and wired and wireless networks
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The teaching part (1 min) is free to watch. A free account opens the whole lecture: 5 practice questions, 2 real past-paper questions with the answers explained, the mistakes that lose marks, the full-marks tip, a one-card summary and a quick quiz.
What this lecture covers
- A room, a campus, a country
- LAN and WAN
Read the transcript of the teaching part
Last time
Before we start: last time, in Ethernet, CSMA/CD, LAN hardware and IP addresses, you learned these points. Here they are again on one card. Keep them in mind, because today builds on them.
A room, a campus, a country
A network joining the computers in one room is small and private. A network joining a head office to branches in other cities is large and rented from others. How the devices are wired together, the topology, decides what happens when a cable breaks, and whether you use cables or radio waves decides speed, cost and security.
LAN and WAN
A local area network covers a small area, such as a building or campus. The organisation owns the cables and equipment. A wide area network covers a large area, such as cities or countries. It uses links leased from telecommunications companies, and the internet is the biggest WAN. LANs are usually faster and cheaper to run per device. WANs have lower speeds and higher costs, but reach far.
Chapter 2: Communication
- Bit streaming, client-server, peer-to-peer and cloud computing 6 min
- Ethernet, CSMA/CD, LAN hardware and IP addresses 7 min
- LAN, WAN, topologies and wired and wireless networks 7 min
Also for A Level Computer Science 9618
Which topics come up most in A Level Computer Science 9618 past papers, counted from every paper since 2004: Paper 1 topic frequency, Paper 2 topic frequency.