Edexcel GCSE Computer Science (1CP2) Exam Questions

Award one mark for any of the following up to a maximum of two marks:

• A network that covers a large geographical area / connects locations in different cities/countries (1)
• Two or more LANs/local area networks connected together (1)
• Uses infrastructure owned by a third party / rented from a telecoms provider (1)
• Uses leased lines (1)

Allow 'two or more networks connected together' only if the answer says they are in different/remote locations.

Do not accept a network that covers a small area / is on one site, as this describes a LAN.

Do not accept 'wide' on its own without saying what it means.

Do not accept that devices can share data/resources over a long distance on its own, as this is a purpose of a WAN and not a defining feature.

Award up to two marks for a linked explanation such as:

• The router reads the destination IP address (1) so it knows which network/device the packet is for (1)
• The router looks up the destination IP address in its routing table (1) to find the next router/route for the packet (1)
• The router forwards the packet to the next router (1) that leads towards that IP address / is on the best route (1)

For both marks, the expansion must follow/associate with the statement.

Do not accept MAC address - routers use the IP address to route packets between networks.

Do not accept 'it finds the exact device' without saying how the router uses the address, e.g. routing table/next router.

Award up to two marks for a linked explanation such as:

• Wireless signals can be blocked or absorbed by walls (1) so the data must be re-sent, which adds delay (1)
• A device further from the access point has a weaker signal (1) so data must be re-sent/transmitted at a lower rate, adding delay (1)
• Devices on a wireless network share a channel (1) so a device must wait its turn to transmit, which adds delay (1)
• Interference from other devices affects the radio signal (1) so data must be re-sent, adding delay (1)

For both marks, the expansion must follow/associate with the statement.

Allow 'waiting to send' or 'collisions' as the delay caused by devices sharing a channel.

Do not accept 'wireless is slower than wired' on its own, as this repeats the question.

Do not accept a reason that only affects download speed/bandwidth (e.g. 'files take longer to download') without a link to delay.