14. Communication and Internet Technologies
Protocols (TCP/IP stack, HTTP, FTP, SMTP, POP3, IMAP, BitTorrent), circuit and packet switching in depth.
Statometer55CoreNext Paper 395%Everything for this topic — study hub
A2 Level · 9618 · Paper 3
This topic is rows 4–5 of the study route.Open it on your study route
Statometer — what 32 real papers say about this topic and each of its 2 syllabus bullets
Core · #6 of 8 in A2 Level · recomputed with every new session
A regular, well-paid topic — you cannot afford a gap here.
- Next Paper 3
- 95%
- 9 in 10 chance it is set
- Marks a paper
- 7.7 / 75
- 10% of Paper 3 · fair share 17%
- Appeared in
- 32 / 32
- Paper 3 sittings 2021–2026
- Last set
- May/Jun 2026
- 9618/33 · Q2 · 4 marks · 11-series streak
What the papers say
- Set in 32 of 32 Paper 3 sittings on the current syllabus — treat it as certain.
- Worth about 7.7 marks a paper (10% of Paper 3).
- Last set May/Jun 2026 · 9618/33 · Q2 for 4 marks — in the most recent series.
- Set in each of the last 11 series without a miss.
- Easing off: about 8.5 marks a paper earlier, 7.3 in the latest years — still examined, just smaller.
- Lives on “Explain” and “Describe” — 69% of its questions: full sentences with a reason, not one-word answers.
- 33% of its questions involve a diagram, table or figure — practise with pen and paper.
- Its biggest question so far: 10 marks (Oct/Nov 2025 · 9618/31 · Q3).
- Inside the topic, §14.1 Protocols carries the most marks (56%) and §14.2 Circuit switching and packet switching the least (45%).
- It is examined almost entirely as AO1 (Knowledge & understanding, 97%) — definitions and descriptions in syllabus words score.
- The examiner has commented on 58 of its questions — read “What the examiner said” before you practise.
Command words
Share of questions using the word (a question can use several). What each wants →
Question shapes
- ≤ 6 mk31
- 7–9 mk20
- 10–12 mk19
- 13–15 mk12
- 16+ mk5
Average 8.8 marks a question · 33% with a figure or table · 24% with code · biggest 10 marks
Assessment objectives — how it is examined
Every part of every current-syllabus question filed under Cambridge's AO1 / AO2 / AO3 (from its command word and what it asks you to do), so you know whether this topic pays for definitions, for applying, or for judging and building.
- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
Paper 3 as a whole
| Paper 3 | Syllabus | Measured |
|---|---|---|
| AO1 Knowledge & understanding | 60% | 54% |
| AO2 Apply & analyse | 40% | 46% |
| AO3 Design, program & evaluate | 0% | 0% |
Syllabus = Cambridge's grid; measured = the bank's current-syllabus papers.
Inside the topic — every syllabus bullet, measured
Each part of each question is filed under the bullet it examines; the numbers are per Paper 3 sitting, exactly like the topic's. Open a bullet for its own Statometer.
14.1Protocols#5 of 14 on Paper 3Core · 7185% next paper4.8 marks27/32 sittings→ May/Jun 2026Core · 7185%
4.8 · 56% of topic27/32May/Jun 2026latest series · →A regular earner inside the topic — most papers touch it.Syllabus: why protocols are essential; protocol stacks; the four-layer TCP/IP suite and what happens when a message crosses the internet; HTTP, FTP, POP3, IMAP, SMTP and BitTorrent
- Next Paper 3
- 85%
- 9 in 10
- Marks a paper
- 4.8
- 7% of the paper · 56% of the topic
- Asked in
- 27 / 32
- Paper 3 sittings · 60 questions
- Last asked
- May/Jun 2026
- 9618/33 · Q2 · 4 marks · 6-series streak
- Asked in 27 of 32 Paper 3 sittings — about 8 papers in 10.
- About 4.8 marks a paper (7% of Paper 3; 56% of the topic's marks across its 2 bullets).
- Last asked May/Jun 2026 · 9618/33 · Q2 (4 marks) — in the most recent series.
- Asked in each of the last 6 series.
- Usually “Describe” or “Explain”: full sentences with a reason, not one-word answers.
- Biggest chunk of marks so far: 8 in May/Jun 2022 · 9618/32 · Q3.
- It is examined almost entirely as AO1 (Knowledge & understanding, 95%) — definitions and descriptions in syllabus words score.
Last 12 sittings→ SteadyAssessment objectives
AO1 95%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- Describe43%
- Explain43%
- State35%
- Identify28%
14.2Circuit switching and packet switching#10 of 14 on Paper 3Regular · 4456% next paper2.8 marks19/32 sittings↘ Oct/Nov 2025Regular · 4456%
2.8 · 45% of topic19/32Oct/Nov 20251 series ago · ↘Set most sessions for a few marks; know the definition and one example.Syllabus: benefits, drawbacks and where each applies; the router's role in packet switching; how packets are passed across a network
- Next Paper 3
- 56%
- 6 in 10
- Marks a paper
- 2.8
- 4% of the paper · 45% of the topic
- Asked in
- 19 / 32
- Paper 3 sittings · 50 questions
- Last asked
- Oct/Nov 2025
- 9618/33 · Q3 · 4 marks · 1 series ago
- Asked in 19 of 32 Paper 3 sittings — about 6 papers in 10.
- About 2.8 marks a paper (4% of Paper 3; 45% of the topic's marks across its 2 bullets).
- Last asked Oct/Nov 2025 · 9618/33 · Q3 (4 marks), 1 series ago.
- Easing: 3.5 → 2.3 marks a paper.
- Usually “Explain” or “State”: full sentences with a reason, not one-word answers.
- Biggest chunk of marks so far: 8 in May/Jun 2022 · 9618/31 · Q3.
- It is examined almost entirely as AO1 (Knowledge & understanding, 100%) — definitions and descriptions in syllabus words score.
Last 12 sittings↘ EasingAssessment objectives
AO1 100%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- Explain50%
- State48%
- Describe42%
- Give34%
9% of the topic's marks sit in question parts that belong to another topic (scenario questions cross sections) or that no bullet claims; they count for the topic, not for a bullet.
Marks a paper, year by year
Grey years are the previous syllabus (2015–2021, 49 questions) — history, not counted in the rates.
By exam series
- May/Jun18/18 · 7.7 mk
- Oct/Nov14/14 · 9.1 mk
What you need to know2syllabus §14.1, §14.2
- 14.1Protocols — why protocols are essential; protocol stacks; the four-layer TCP/IP suite and what happens when a message crosses the internet; HTTP, FTP, POP3, IMAP, SMTP and BitTorrent
- 14.2Circuit switching and packet switching — benefits, drawbacks and where each applies; the router's role in packet switching; how packets are passed across a network
Video lectures10ZAK's YouTube channel · play here
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Infographics3draw these the way the examiner expects · download as PNG
Circuit vs packet switching
TCP/IP protocol stack
Application protocols & BitTorrent
Key terms13use these exact words in the exam
Dotted terms are defined in the glossary.
Code help1referenced to the Cambridge pseudocode guide
DECLARE Seq : ARRAY[1:4] OF INTEGERDECLARE Payload : ARRAY[1:4] OF STRINGDECLARE Msg : STRINGDECLARE i, Want : INTEGERSeq[1] ← 3Payload[1] ← "ZAK"Seq[2] ← 1Payload[2] ← "CS "Seq[3] ← 4Payload[3] ← "!"Seq[4] ← 2Payload[4] ← "with "Msg ← ""FOR Want ← 1 TO 4FOR i ← 1 TO 4IF Seq[i] = Want THENMsg ← Msg & Payload[i]ENDIFNEXT iNEXT WantOUTPUT Msg
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