The TCP/IP protocol suite has four layers: Transport, Application, Link, Internet

Mark scheme

Marking points from the official mark scheme (May/June 2024). The mark or mark type is shown in brackets.

1. [2] 2(a) Two marks for all protocols in correct position
2. 2(a) One mark for at least two protocols in correct position
3. 2(a) Application
4. 2(a) Transport
5. 2(a) Internet
6. 2(a) Link
7. [2] 2(b) One mark per mark point (Max 2)
8. 2(b) MP1 The transport layer is responsible for delivery of data from the source host to the destination host
9. 2(b) MP2 It is where data is broken up into packets and sent to the internet layer
10. 2(b) MP3 Adds the sequence number to the packet header
11. 2(b) MP4 It establishes end to end contact
12. 2(b) MP5 It ensures data arrives error free // It retransmits packets if lost.
13. [2] 2(c) One mark for name of protocol and one mark for expansion (Max 2)
14. 2(c) HTTP(S) – responsible for correct transfer of files / hypertext documents that make up web pages on the world wide web
15. 2(c) FTP - used when transferring files from a server to a client on a network
16. 2(c) POP3 - handles the receiving of emails
17. 2(c) IMAP – handles the receiving of emails
18. 2(c) SMTP – handles the sending of emails
19. 2(c) BitTorrent - provides peer-to-peer file sharing