Edexcel GCSE Computer Science (1CP2) Exam Questions

• B Internet (1)
• The only correct answer is B. The correct answer is Internet.
• A is not correct because the application layer creates data for applications such as web browsers and does not route packets
• C is not correct because the link layer sends data over physical hardware using MAC addresses and does not route packets
• D is not correct because the transport layer sets up the connection between two computers and reassembles the packets

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 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.