GCSE (9-1) Computer Science
Mark Scheme
J277/01: Unit 1.3 Networks
Question Answer Marks Guidance
1
  • Large geographical area: WAN
  • Infrastructure owned by org: LAN
  • Uses third-party infrastructure: WAN
  • Single site or building: LAN
4
AO1 (Knowledge)
1 mark per correct tick.
If a candidate ticks both boxes in a single row, award 0 marks for that row.
2a LAN / Local Area Network 1
Accept: WLAN (Wireless LAN).
2b WAN / Wide Area Network 1
2c 1 mark for geographical scale:
  • It is on a single site / small geographical area.
1 mark for infrastructure/ownership:
  • The school owns the cabling/hardware.
  • They do not use external/leased lines.
2
NE (Not Enough): "It is close together" or "In a building" without the concept of single site or small geographical area.
To get the ownership mark, they must imply the school controls the connection (not a telecom company).
3 Difference 1 (Geography):
LAN covers a small geographical area (e.g. a house/school) (1)...
...Whereas a WAN covers a large geographical area (e.g. country/world). (1)

Difference 2 (Infrastructure/Ownership):
LAN infrastructure/hardware is owned by the organisation (1)...
...Whereas WANs use third-party / leased infrastructure (e.g. BT, satellites, fibre cables). (1)
4
AO1 (Understanding)
Be strict on "infrastructure".
Allow: "Hired connections", "Telecommunication companies", "Leased lines" for WAN.
Reject: "WANs are wireless" (Both can be wireless).
Reject: "WANs are faster" (LANs are typically faster, but speed is not a defining definition in the spec).
4a WAN / Wide Area Network 1
4b 1 mark for third-party concept:
  • It uses third-party / external infrastructure (cables/satellites).
1 mark for explanation:
  • No single person/organisation owns the entire infrastructure / it connects networks across the world.
2
AO1/AO2
The key here is that the Internet is a collection of networks connected via infrastructure we do not own individually. Focus on the "hired/leased" aspect.
5 Router 1
Required to connect different networks (LAN to WAN).