Edexcel GCSE Computer Science (1CP2) Exam Questions

• A It is not affected by interference from other wireless devices (1)
• The only correct answer is A. The correct answer is that a wired connection is not affected by interference from other wireless devices.
• B is not correct because a wired connection does not let staff move around the office; being able to move around is a benefit of a wireless connection
• C is not correct because a new device needs a cable and a free port to join a wired network, which takes longer than joining a wireless network
• D is not correct because a wired connection does need a cable; it is a wireless connection that does not need one

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:

• A home network (1)
• A school network / a network within a school (1)
• An office network / a network within one business building (1)
• A hospital network (1)
• A hotel network (1)

Allow a named organisation on a single site/premises, e.g. one shop, one café (1)

Do not accept the internet.

Do not accept an organisation with offices/branches in different countries / a university with campuses in different cities.

Do not accept 'LAN' / 'local area network' on its own.

Do not accept 'a network' with no context.

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

• Each node/device has multiple direct connections to other nodes/devices (in a full mesh, every node is connected directly to every other node) (1)
• There is no central device/switch (1)
• Nodes act as routers/relay data for other nodes / data can take multiple/different routes to its destination / data can still be sent if a connection/node fails (1)
• More connections/cables are needed as the number of nodes increases (1)
• The network can be expanded without disrupting existing devices (1)

Allow answers that refer to full or partial mesh.

Allow 'more connections/cables are needed' and 'can be expanded' as characteristics (they may be described as advantages or disadvantages).

Do not accept 'more secure' or 'no collisions' without qualification.

Do not accept 'fast' or 'reliable' without qualification.

Do not accept all devices connect to one main cable (this describes a bus topology).

Do not accept it uses a central switch/hub or data is sent through a central hub (this describes a star topology).

Do not accept 'expensive' without qualification (e.g. because more cables/connections are needed).

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

• A delay/time/lag (1)
• Between a signal/request being sent and a response/data being received (1)

Allow 'the time taken for data to travel from source to destination' for both marks.

Do not accept 'the speed at which data travels' / 'bandwidth' / 'the amount of data sent per second'.

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

• 300 million bits (1) are transferred/downloaded every second (1)
• 300 megabits of data (1) are received each second (1)
• Each second (1) 300,000,000 bits arrive at the device (1)
• The connection can receive (1) 300 megabits of data in one second (1)

Allow '300 million bits per second' (2) as it states both the quantity and the time.

Accept 'megabits', 'Mb' or 'Mbps' as the unit of bits.

Do not accept 'megabytes'/'MB' or answers that give no unit of bits, e.g. '300 units of data per second'.

Do not award marks for simply repeating the question, e.g. '300 megabits per second' or 'it has a speed of 300 Mbps', with no statement of the data transferred/received and the time.

Do not accept answers that only say the connection is fast.

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

• The switch receives the data/a packet from the sending device (1) and forwards it only to the destination device (1)
• Acts as a central connection point for the devices (1) so any device can send data to any other device on the network (1)
• Sends data to the correct device (1) so the other devices on the network do not receive it (1)

For the central device, accept 'switch'. Do not accept 'server'.

Do not accept 'hub' where the response says data is sent only to the destination device (a hub sends data to every device).

Do not accept 'it connects the network to the internet'.

Award a maximum of one mark where a point is made without a linked development.

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

• Each device/node is connected to more than one other device (1) so there is another route for the data to take (1)
• Data can be sent along a different path (1) to bypass the failed connection (1)
• There is no central device/switch to fail (1) so data can still be passed between the remaining devices (1)

Allow 'sensor' or 'node' for device.

Do not accept 'the failed connection repairs itself' or 'the data is stored until the connection works again'.

Do not accept responses that say a central switch sends the data by another route, as a mesh has no central device.

Do not award generic statements such as 'a mesh is reliable/resilient' without a description of how the data still reaches its destination.

Do not award descriptions of a bus or star network failing.

Accept a reference to a device failing only where the candidate also states that other connections/routes remain available.

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 explanation such as:

• The offices are a large distance apart/in different countries (1) so a WAN connects the separate networks over a large geographical area (1)
• A WAN connects two or more LANs together (1) so the separate office networks can communicate (1)
• A WAN can use leased lines rented from telecommunications companies (1) because the company does not own the long-distance cabling between countries (1)

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

Allow 'a WAN covers a large geographical area' as the WAN feature (1) when linked to the company's offices being in different countries/cities (1).

Allow leased lines rented from telecommunications companies as the WAN feature (1) if linked to the company not owning the long-distance cabling (1).

Do not accept 'a WAN is bigger/faster' without saying that it connects networks over a large distance.

Do not accept 'the offices are in different countries' on its own as a linked explanation, because it does not state a WAN feature.

Do not accept 'WAN covers a large area' on its own without linking it to the company's offices.

Do not accept 'the internet is a WAN' on its own.

Do not accept 'more secure/safer' on its own because this does not explain the need to connect distant offices.