Edexcel GCSE Computer Science (1CP2) Exam Questions

• B Router (1)
• The only correct answer is B. The correct answer is Router.
• A is not correct because a hub sends the data it receives to every device on the network
• C is not correct because a server provides services, such as web pages, to client computers
• D is not correct because a switch forwards data between the devices on one network

• B Higher data transfer speed (1)
• The only correct answer is B. The correct answer is higher data transfer speed.
• A is not correct because the 2.4 GHz band has the greater range
• C is not correct because the 2.4 GHz band passes through walls more easily
• D is not correct because the 5 GHz band does not use less bandwidth

Award one mark for:

• 0 to 255 (1)

Allow 0–255 / 0-255 / between 0 and 255 / 0 and 255.

Do not accept 1 to 255 (0 is a valid value).

Do not accept any range that includes 256, e.g. 0 to 256.

Award one mark for:

• The maximum distance data/a signal can be transmitted before it becomes too weak to be received (1)

Allow 'how far a signal can travel'.

Do not accept the number of devices that can be connected to the network.

Do not accept the speed at which data is transmitted.

Do not accept bandwidth/the maximum capacity of a channel.

Do not accept latency/the delay between a signal being sent and received.

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

• Faster transmission speed (1)
• Higher bandwidth (1)
• Lower latency (1)
• Not affected by interference (from other devices/walls) (1)
• No blind spots/not affected by distance from the wireless access point (1)

Do not accept benefits of wireless connections, e.g. users can move around the building with their devices

Do not accept 'easier to set up' or 'does not need a password' as these are not about network performance

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

• Bandwidth is the maximum amount/capacity of data that can be carried each second (1) so a higher bandwidth lets editors open the large video files from the server in less time (1)
• The bandwidth of the cable is set by the type/standard of cable used (1) so it limits how much of a large file can be sent in a given time (1)
• A higher bandwidth means the cable can be shared between more transfers at the same time (1) so several editors can open files from the server at once without their transfers slowing down (1)
• If the bandwidth is too low for the size of the files (1) the transfers take a long time and the editors have to wait for their files to open (1)

Allow 'capacity' for 'maximum amount of data'.

A description that only defines bandwidth earns a maximum of one mark.

Do not accept responses about the time a signal takes to travel (latency) or the distance a signal can reach (range).

Do not accept answers that say bandwidth is how fast the signal/data travels along the cable, that a higher bandwidth gives a faster internet connection, or that bandwidth is the number of cables in the network.

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

• (Twisted pair/copper) cable only carries data over a limited distance (about 100 metres) (1) so sensors further away need another switch/device to pass the data on to the farmhouse (1)
• Fibre optic cable can carry data over much longer distances (1) so wired connections can reach sensors across the whole farm (1)
• Data sent further than the cable's range is not received (1) so the computer in the farmhouse does not get readings from those sensors (1)
• A wireless connection can reach sensors that are out of range of the cables (1) so a mix of the two can give readings across the whole site (1)

Allow responses about signal weakening/being lost over a long cable.

Do not accept responses about bandwidth or speed, as range is about distance, not the amount or rate of data.

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

• Splits the data/file into packets (1) so each packet can be sent separately across the network (1)
• Adds a packet/sequence number to each packet (1) so the packets can be put back into the correct order at the destination (1)
• Detects lost/missing packets (1) so they can be requested/resent (1)
• Creates a connection between the two computers/hosts (1) before the file is sent (1)

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

Allow 'segments' for 'packets' (TCP divides the data into segments, which become packets at the internet layer).

Do not accept 'sends the data/file' on its own without saying what the transport layer does to the data.

Do not accept naming TCP or a port number on its own without expansion.

Do not accept routing/addressing packets using IP addresses, which is the internet layer.

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

• Devices near the edge/limit of the range receive a weaker signal/lower signal strength (1) so data is transferred more slowly/the connection speed/bandwidth is lower (1)
• Devices near the edge/limit of the range receive a weaker signal/lower signal strength (1) so latency increases (1)
• Devices outside the range cannot connect to the access point (1) so users in that area cannot use the network/access its resources (1)
• A device that moves out of range loses its connection (1) so the user's work is interrupted until it is back in range (1)

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

For the second mark, the reason must state the effect on the user/network (e.g. cannot use the network/access resources, slower speed, higher latency), not just repeat that the device is out of range.

Do not accept a definition of range on its own (e.g. 'range is how far the signal reaches') without an effect on performance.

Do not accept 'a larger range means more devices can connect' (range is not about the number of devices/capacity).

Do not accept range confused with bandwidth/speed, e.g. 'range is the maximum amount of data that can be transferred'.