Chapter 21: Networks and Web Technologies: Structure of the Internet

A-level Computer ScienceOCR6 topicsHigher

StudyStudy Material QuizQuiz ResourcesResources

Mock Papers

Exam-board mock papers

Mock papers launch from 1 August 2026. New papers will be added regularly from this date.

Dashboard tracking

Included with paid subject access

You can see the paper details now. Access unlocks when your plan includes this subject and tier.

Mock paperFeatured

Mock papers launch collection

alevel · computer-science · OCR · All papers

Releases 1 August 2026

Locked

Topic-aware long answers

Ultimate/Lifetime long-answer set

Ultimate and Lifetime users can create one saved set of 4 extended-response questions for this topic and mark answers with examiner-style feedback.

AI MCQ generation is available to paying students: 20 questions per session,2 sessions per month. Long-answer AI generation requires Ultimate or Lifetime access.

Free starter set

Translators and Compilation Long-Answer Questions

Examiner-style long-answer practice with automatic marking, improvement advice and ProofCoach tracking.

4 questions24 marks36 min

standard / hard / synoptic

6 marksdescribestandardOCR A

CS21-1 translation: describe how lexical analysis, parsing, optimisation and code generation operates in turning source code into executable machine code, using precise OCR H446 terminology.

0 characters

Write your answer first, then mark it.

6 marksexplainstandardOCR A

CS21-2 applied case: explain why lexical analysis, parsing, optimisation and code generation would affect turning source code into executable machine code, including one limitation or trade-off.

0 characters

Write your answer first, then mark it.

6 markswritehardOCR A

CS21-3 task for translation: write a response using lexical analysis, parsing, optimisation and code generation in turning source code into executable machine code; produce a compiler-stage sequence.

0 characters

Write your answer first, then mark it.

6 marksevaluatesynopticOCR A

CS21-4 synoptic judgement: evaluate the suitability of lexical analysis, parsing, optimisation and code generation for turning source code into executable machine code, comparing it with one credible alternative.

0 characters

Write your answer first, then mark it.

Subject MCQ Bank

20 stored MCQs for this topic

Paying students get 20 stored MCQs per generation session and 2sessions each month. Your set is saved here so you can reset and retake it without using another allowance. If the bank is running low, replenishment happens in the background.

The 20-question stored MCQ bank is premium-only. Free users can study the starter unit and standard quiz, but bank practice unlocks after purchasing the subject.

Loading practice tools...

← Previous

20. Exchanging Data: Transaction Processing

22. Networks and Web Technologies: Internet Communication

Key learning objectives

Understand the key principles behind Networks and Web Technologies: Structure of the Internet.
Apply these ideas to exam-style questions.
Recall the essential definitions and key terms.