Process
WJEC A-Level Computer Science 601-5345-3
Hardware: Architecture, Memory and Storage
Networks and Data Transmission
Logic Gates and Boolean Algebra
Data Representation and Data Types
Data Structures
Organisation of Data: Files and Records
Database Systems
The Operating System
Algorithms and Programs
Principles of Programming
Systems Analysis
Software Engineering and Program Construction
Topic overviewIntegrated development environments and their purposeEditors, syntax highlighting and code entry toolsDebugging tools: breakpoints, stepping and watchesTranslation, source code and object codeLexical analysis and the symbol tableSyntax and semantic analysisCode generation and optimisation
Types of Software System
Practical Programming
Data Security and Integrity
Computing, Society and the Law
Topic overviewSocial and economic change from computingComputers and the nature of employmentThe digital divide and cultural changeEnvironmental cost of computingData protection and freedom of information lawThe Computer Misuse Act 1990 and computer crimeCopyright, surveillance and professional codes
Advanced Data Structures and Logic
Recursion, Sorting and Searching
Programming Paradigms and Translators
Topic overviewFunctional, declarative and imperative paradigmsClasses, methods and object-oriented designStandardisation of computer languagesAmbiguity in natural language and unambiguous notationBackus-Naur form and syntax diagramsCompilers, interpreters and assemblersTranslation and execution errors
System Design and Human-Computer Interaction
Software Engineering Tools and Professional Practice
Topic overviewSoftware tools for the software engineering processSoftware packages in systems analysis and specificationSoftware packages in systems designTesting tools and testing strategiesProgram version managementProgram libraries and project management toolsCodes of conduct and professional behaviour
Advanced Architecture and Assembly Language
Communication Networks and File Organisation
Number Representation and Floating Point
Databases and Distributed Systems
Topic overviewConsistency, redundancy and data independenceRelational organisation and normalisationRestructuring data into third normal formEntity relationship modellingQuery languages and SQLValidation, verification and the DBMSBig Data, data warehousing and miningDistributed systems and distributed databases
Operating System Management
Software Systems and Applications
Data Security, Cryptography and Attack
Communication Networks and File Organisation
- 7 subtopics
- 21 things to know
- A2 Unit 4
What Communication Networks and File Organisation covers
Communication Networks and File Organisation is examined in A2 Unit 4, Computer Architecture, Data, Communication and Applications. It covers calculating data transfer rates, lowest-cost routing, the internet as a global infrastructure, creating, organising and processing files, hashing algorithms, overflow and file reorganisation and choosing an organisation and a route.
Where it is assessed
A2 Unit 4
Computer Architecture, Data, Communication and Applications.
Check the WJEC specification ↗The 7 subtopics
Each one has its own page.
- Calculating data transfer ratesRelationship between file size, transfer rate and time, protocol overhead and bottleneck on a route.Open →
- Lowest-cost routingNetwork represented as, for the purposes of routing, algorithm used to find a lowest-cost route and first step of Dijkstra's algorithm.Open →
- The internet as a global infrastructureInternet service provider, internet exchange point and packet switching.Open →
- Creating, organising and processing filesSerial file organisation, sequential file organisation and indexed sequential organisation.Open →
- Hashing algorithmsHashing algorithm, in the context of file organisation, purpose of hashing and folding method.Open →
- Overflow and file reorganisationOverflow, in a hashed file, open or linear probing method of handling overflow and use of a separate overflow area.Open →
- Choosing an organisation and a routeCost of maintaining an index, trade-off in choosing the size of a hashed address space and balanced conclusion about file organisation.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Key term
Show the three methods of turning a key into an address at work, and say what none of them can avoid.
Key term
How do serial, sequential and indexed sequential organisation differ, and what does the last of them make possible?
Key term
What is bandwidth?
Key term
What is the internet?
Key term
What is overflow, in a hashed file?
Key term
Why is there no single best file organisation?
Key term
Distinguish bandwidth from throughput.
Key term
What is a network represented as, for the purposes of routing?
Key term
Distinguish the internet from the World Wide Web.
Key term
What is a file?
Key term
What is a hashing algorithm, in the context of file organisation?
Key term
Describe the open or linear probing method of handling overflow.
Process
Which organisation suits a file processed in full each run and never accessed singly?
Key term
State the relationship between file size, transfer rate and time.
Key term
What can the weight on an edge represent?
Key term
What physically carries most long-distance internet traffic?
Key term
What is a record?
Key term
Give a simple hashing algorithm.
Evaluation
Give one disadvantage of linear probing.
Key term
Which organisation suits a file where single records are looked up at random and never listed in order?
Take Communication Networks and File Organisation further
The same content, four other ways.
Questions from this topic
Each one with the model answer underneath.
- 1
What is bandwidth?
Model answer
The maximum rate at which data can be carried by a channel, measured in bits per second.
- 2
Distinguish bandwidth from throughput.
Model answer
Bandwidth is the theoretical maximum of the channel; throughput is the rate actually achieved once overheads, errors and contention are taken into account.
- 3
State the relationship between file size, transfer rate and time.
Model answer
Time equals the amount of data divided by the transfer rate, with both in matching units.
- 4
How long does a 12 megabyte file take over a 4 megabit per second link?
Model answer
12 megabytes is 96 megabits, so 96 divided by 4 gives 24 seconds.
- 5
Why must the byte figure be converted to bits first?
Model answer
Transfer rates are quoted in bits per second and file sizes in bytes, so dividing without converting understates the time eightfold.
- 6
A 500 megabyte backup must complete in 200 seconds. What rate is needed?
Model answer
500 megabytes is 4,000 megabits, so 4,000 divided by 200 gives 20 megabits per second.
What is inside Levo
Six ways to work the same material.
Communication Networks and File Organisation revision questions
- What does Communication Networks and File Organisation cover in WJEC A-Level Computer Science?
- 7 subtopics: calculating data transfer rates, lowest-cost routing, the internet as a global infrastructure, creating, organising and processing files, hashing algorithms, overflow and file reorganisation and choosing an organisation and a route. Each one has its own page with questions and model answers.
- How is Communication Networks and File Organisation organised?
- By the WJEC 601-5345-3 specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Communication Networks and File Organisation, on a schedule.
Attempt a question from memory, write the correct version, then attempt it again. Levo records the jump between your first attempt and your last, and brings each question back on the day you are due to forget it.
Or £46 a year, about £3.83 a month. Cancel anytime.