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

4 questions · 7 marks

Pick again
Print
1Short recall1 markAddressing Swap Remove

Routers forward data packets across the internet.

State the part of a data packet that a router uses to decide where to send it.

[1 mark]
Mark scheme

Award one mark for:

  • (Destination) IP address (1)

Allow IP address on its own (the destination is implied).

Do not accept source IP address/IP address of the sender.

Do not accept MAC address.

Do not accept domain name/web address.

Example answers and how they were marked
Full marks1/1

The destination IP address.

Why: Names the destination IP address (1).

No marks0/1

The domain name.

Why: A domain name is not used by a router to route a packet; it must be translated to an IP address first, so no mark.

No marks0/1

The MAC address.

Why: A MAC address is not used to route packets across the internet; the Do not accept line applies.

2Explain2 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'.

3Explain2 marksTopologies Swap Remove

A small office uses a star topology with a central switch.

Explain one benefit of using a star topology in the office.

[2 marks]
Mark scheme

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

  • If one cable/device fails, the other devices on the network are not affected (1) because each device has its own separate connection to the central switch (1)
  • Faults are easier to find (1) because each device has its own cable, so the faulty cable can be checked on its own (1)
  • Data is sent only to the intended device (1) because the central switch forwards the data only to the device it is addressed to (1)
  • Data transfer is fast (1) because each device has its own cable, so devices do not share the cable with each other (1)
  • New devices can be added easily (1) because a device only needs one cable to a spare port on the central switch (1)

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

A benefit stated on its own can earn one mark; the second mark is only for a linked reason.

Accept 'switch' for the central device.

Do not accept 'server' or 'hub' for the central device.

Do not accept 'hub', as a hub sends data to all devices, not only to the intended device.

Do not award a mark for responses that say only that the network is better/more reliable/easier without naming a benefit.

Example answers and how they were marked
Full marks2/2

If one of the cables breaks, the other devices can still communicate because each device has its own separate cable connected to the central switch.

Why: Linked benefit (1) and reason (1): a single cable failure does not affect the other devices because each device has a separate connection to the switch.

Some marks1/2

If one cable breaks, the other devices are not affected.

Why: A benefit is stated on its own (1), but there is no linked reason about each device having its own connection to the central switch, so the second mark is not awarded.

No marks0/2

It is better than a bus topology because every device connects to the central server.

Why: No credit: 'better' does not name a benefit, so no first mark, and 'server' is not accepted as the central device, so there is no linked reason either.

4Explain2 marksWireless Connections Swap Remove

A student plays an online game using a laptop connected to the school Wi-Fi.

Explain one reason why an online game can respond more slowly over a wireless connection than over a wired connection.

[2 marks]
Mark scheme

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.

Example answers and how they were marked
Full marks2/2

Interference from other devices affects the radio signal, so the data has to be re-sent and this adds delay before the player's action appears.

Why: Linked point (1): interference affects the signal; reason (1): re-sending the data adds delay (latency).

Some marks1/2

Walls can block the wireless signal.

Why: Point only (1): walls block the signal. No linked reason saying that this means data must be re-sent, which adds delay.

No marks0/2

Wireless has less bandwidth than wired, so a game update takes longer to download.

Why: Confuses latency with bandwidth/download speed; the mark scheme says not to accept this without a link to delay.

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.