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S6 ICT: Data Communications and Networking (Paper 3 (challenge))
S6 ICT: Data Communications and Networking (Paper 3 (challenge))
Paper 3 (challenge): 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)
- FoundationHow do a hub and a switch differ in forwarding?
- FoundationWhich range is private: 192.168.0.0/16 or 203.0.113.0/24?
- FoundationWhat is the difference between full duplex and half duplex?
- IntermediateWhat does NAT do?
- IntermediateWhat is the benefit of layering network protocols?
- IntermediateShould a wireless network use WPA3 or WEP?
- ChallengeA 750 MB file is sent at 50 Mbps. How many seconds does it take?
- ChallengeHow many usable host addresses does a /28 subnet mask give?
- ChallengeA 4 GB file is sent at 100 Mbps. How many seconds does it take? (1 GB = 1024 MB, one decimal place)
- Error redoError clinic: adding bandwidth always makes a website load faster. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | A hub repeats to every port, while a switch sends only to the correct port by MAC address | Broadcasting makes computers compete for the link, raising collisions and privacy risk. |
| 2 | 192.168.0.0/16 is private | Private ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. |
| 3 | Full duplex sends and receives at the same time, while half duplex allows one direction at a time | Half duplex must turn the link around, so it is less efficient. |
| 4 | It translates private IP addresses into a public address when traffic leaves | Many internal computers can share one public address, which also hides the internal layout. |
| 5 | Each layer can change independently and upper layers ignore lower layer details | For example, changing the medium does not touch the application, so maintenance and standardisation are easier. |
| 6 | WPA3, because WEP encryption is broken | WEP keys can be cracked quickly, so WPA2 or WPA3 should be used instead. |
| 7 | 120 seconds | 750 multiplied by 8 gives 6000 megabits, which divided by 50 gives 120 seconds. |
| 8 | 14 addresses | Host bits are 32 minus 28, which is 4, and two to the power four minus two gives 14. |
| 9 | About 327.7 seconds | 4 times 1024 times 8 gives 32768 megabits, which divided by 100 gives 327.68 seconds. |
| 10 | Latency, server processing time and packet loss also matter | Bandwidth only shortens the transfer of large amounts of data, while small single requests are limited mainly by latency. |
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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