Menu

Edexcel GCSE Computer Science (1CP2) Exam Questions

Build a practice paper from 693 exam-style questions, each with its mark scheme and example answers. Print it, or answer it on paper and then open the mark schemes. Or browse the questions by topic.

Build a paper

Topics (none ticked: all of them)
Question types (none ticked: all of them)

Practice paper

2 questions · 4 marks

Pick again
Print
1Explain2 marksPacket Switching Swap Remove

Data is split into packets before it is sent across the internet.

Explain why each packet has a packet number in its header.

[2 marks]
Mark scheme

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

  • The receiver can put the packets back into the correct order (1) because packets may arrive out of order/take different routes (1)
  • The receiver can see if a packet is missing (1) because the sequence of numbers shows a gap (1)
  • The receiver knows when the whole file has arrived (1) because the total number of packets/last packet number is known (1)

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

Allow 'so the packets can be put back in the correct order/reassembled' for the first mark, but the second mark needs the reason, i.e. packets may arrive out of order/take different routes.

Do not accept 'so the packets can be identified' without stating what the number is used for, e.g. reordering or spotting a missing packet.

Do not accept 'so the router knows where to send it' - the router uses the destination IP address, not the packet number.

Example answers and how they were marked
Full marks2/2

The receiver can put the packets back in the correct order because they may arrive out of order.

Why: Linked point (1) and reason (1): the packet number allows reordering because packets can arrive out of order.

Some marks1/2

It shows the receiver the order of the packets.

Why: The point is given (1) but there is no linked reason, such as packets arriving out of order.

No marks0/2

So the router knows which route to use.

Why: Routers use the destination IP address, not the packet number, so this earns nothing; it is named in the mark scheme as a 'Do not accept'.

2Explain2 marksLANs & WANs Swap Remove

A charity has one office. All of its computers are in the same building.

Explain one reason why the charity uses a LAN rather than a WAN to connect its computers.

[2 marks]
Mark scheme

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

  • A LAN covers a small geographical area (1) because all the charity's computers are in one building/on one site (1)
  • The charity can use its own cabling/equipment (1) so it does not need to rent leased lines from a telecoms provider (1)
  • The charity owns the infrastructure (1) so it avoids the cost of leased lines/external connections that a WAN needs (1)
  • The devices are close together (1) so the LAN can use short, high-speed cabling (1)

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

Do not accept 'it is faster/better/cheaper' on its own without a linked reason (e.g. short distance, own cabling, no leased lines).

Allow 'the LAN is private/secure' only with a linked reason such as the charity controls its own equipment.

Do not accept 'a LAN is local' or 'a WAN is too far/expensive' without a linked reason about the small area or leased lines.

Do not accept 'the computers are in one building/on one site' on its own because it repeats the stem; it must be linked to a reason such as a LAN covering a small geographical area.

Do not accept 'stronger Wi-Fi/signal' as a reason.

Do not accept 'can share files/printers' on its own because this is a reason for any network, not for choosing a LAN over a WAN.

Example answers and how they were marked
Full marks2/2

All the charity's computers are in one building so a LAN can cover this small geographical area.

Why: Linked point (1) and reason (1): the computers are on one site and a LAN covers a small area.

Some marks1/2

The charity can use its own cabling and equipment.

Why: Earns the first mark for the point about using its own cabling/equipment; it gives no linked reason about avoiding leased lines.

No marks0/2

A LAN is cheaper.

Why: No credit: 'cheaper' on its own is rejected by the mark scheme because it has no linked reason such as avoiding leased lines.

Questions by topic

More ways to revise Edexcel GCSE Computer Science (1CP2)

Teachers: build a paper, print it with the mark schemes at the end, and sign your school up to set your classes activities on every topic.

Fetch Decode Explain isn't affiliated with or endorsed by Pearson Edexcel.