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S6 ICT: Data Communications and Networking (Paper 2 (intermediate))
S6 ICT: Data Communications and Networking (Paper 2 (intermediate))
Paper 2 (intermediate): ten questions on data communications and networking with worked numbers, answers and one line notes.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S6 ICT: Data Communications and Networking |
| Level | S6 |
02 Questions (10 items)
- FoundationIn a star topology, what happens if the central device fails?
- FoundationCompared with twisted pair cable, which resists electromagnetic interference better?
- FoundationHow many bits long is an IPv4 address?
- IntermediateWhat is the main purpose of DNS?
- IntermediateWhat is the main difference between TCP and UDP?
- IntermediateWhich port does HTTPS use by default?
- ChallengeA 5 MB file is sent at 20 Mbps. How many seconds does it take?
- ChallengeHow many usable host addresses does a /26 subnet mask give?
- ChallengeA 60 MB file is sent at 10 Mbps. How many seconds does it take?
- Error redoError clinic: using HTTPS hides the web address. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | All communication in the network stops | Every node connects through the central device, so all traffic fails with it. |
| 2 | Optical fibre | Fibre carries signals as light, so magnetic fields do not affect it and it does not leak signals. |
| 3 | 32 bits | IPv4 uses 32 bits, written as four numbers from 0 to 255. |
| 4 | It translates domain names into IP addresses | After you type a web address, DNS looks up the matching IP so the computer knows where to send the request. |
| 5 | TCP acknowledges and retransmits so it is reliable, while UDP does not and has lower latency | TCP suits file transfer and web pages, while UDP suits live streaming and online games. |
| 6 | 443 | HTTP uses 80, while HTTPS uses 443 with TLS encryption. |
| 7 | 2 seconds | 5 multiplied by 8 gives 40 megabits, which divided by 20 gives 2 seconds. |
| 8 | 62 addresses | Host bits are 32 minus 26, which is 6, and two to the power six minus two gives 62. |
| 9 | 48 seconds | 60 multiplied by 8 gives 480 megabits, which divided by 10 gives 48 seconds. |
| 10 | HTTPS encrypts the content, but the domain and some connection details can still be visible | HTTPS protects what is transmitted and its integrity, yet the domain is usually still visible from the connection. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
Decide first whether a network question is conceptual or numerical. For concepts, separate the device layers: hub, switch and router. For calculations, multiply megabytes by eight to get megabits, then divide by the bandwidth to get seconds. For subnet masks, usable hosts equal two to the power of the host bits, minus two.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.
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