Year 11 · ICT · Summer 1 · Final revision and the exams

Last Paper 1 practice

Exam practicePresent ▶

What this lesson covers

4.2 Network issues and communication

Cambridge IGCSE ICT 0417 · Topic 4: Networks and the effects of using them · Paper 1

6.10 Recognition systems

Cambridge IGCSE ICT 0417 · Topic 6: ICT applications · Paper 1

7.4 Implementation

Cambridge IGCSE ICT 0417 · Topic 7: The systems life cycle · Paper 1

You will learn to

Complete a Paper 1 practice in 1 hour 30 minutes.
Correct every lost mark using the mark scheme.
Describe what to bring and what to do on the day of each paper.

Success criteria

I can finish the paper and check it in the time given.
I can write a full-mark correction for every question where I lost marks.
I can list my exam-day routine for the theory paper and for the practical papers.

The syllabus points for these sections

Explain why data transfer on networks must be kept secure.
Compare strong and weak passwords.
Describe authentication methods: passwords, biometrics, magnetic stripe cards, smart cards, physical tokens, electronic tokens and zero login.
Explain how anti-malware protects a network.
Describe video, audio and web conferencing with advantages and disadvantages.
Describe how OMR and OCR are used, and their advantages and disadvantages.
Explain how ANPR works.
Describe uses of RFID and NFC.
Describe biometric recognition systems.
Describe direct changeover, parallel running, pilot running and phased implementation.
Give advantages and disadvantages of each method.
Choose the most suitable method for a given scenario and justify it.

Key words

Say each word, then read what it means. Every one is in the glossary too.

Network: Two or more devices connected so they can share data and resources.
NIC: Network interface card: hardware that connects a device to a network.
IP address: An address that identifies a device on a network or the internet.
Switch: Connects devices on a LAN and sends data only to the right device, using MAC addresses.
LAN: Local area network: covers one building or site.
Authentication: Proving a user is who they say they are.
Biometrics: Using unique body features such as fingerprints for authentication.
One-time password: A code that works only once, made by a token.
Zero login: Authentication without typing, using biometrics and behaviour.
Anti-malware: Software that detects, quarantines and removes malicious software.
Computer model: A program that uses rules and formulas to act like a real system.
What if: Changing a model's inputs to see what would happen.
NFC: Near field communication: very short-range radio used for phone payments.
ANPR: Automatic number plate recognition: reading number plates from camera images.
GIS: Geographic information system: location data shown as layers on a map.
Systems life cycle: The stages used to create a new system: analysis, design, development and testing, implementation, documentation, evaluation.
Systems analyst: The person who studies the current system and plans the new one.
Questionnaire: A set of written questions given to many people to collect their views.
System specification: A list of the hardware and software the new system needs.
Check digit: An extra digit calculated from the other digits, used to detect input errors.
Data capture form: A paper or on-screen form used to collect data.
Test plan: A table listing each test, its data, the expected and actual outcomes and any remedial action.
Live data: Real data from the organisation, used to test the system with known results.
Direct changeover: The old system stops and the new one starts immediately.
Parallel running: Old and new systems run together until the new one is trusted.
Pilot running: The new system is tried in one branch before the rest.
Phased implementation: The new system is introduced one part at a time across the organisation.

The explanation

Read it here, or open the study page below to go one step at a time with things to try.

The day before

Check the date, the time and the room of each paper.

Two black or dark blue pens for Paper 1.
A simple watch. Smartwatches are not allowed.
Your centre number and candidate number written down, for the practical papers.

★Remember

Sleep is part of revision. A tired brain recalls less. Stop revising early and go to bed.

In the exam room

Paper 1 (theory):

Write your clock times on the front page.
Underline the command word. Circle the marks.
Answer every question. A blank always scores zero.
Use the last 10 minutes to check.

Papers 2 and 3 (practical):

Read the whole paper first.
Put your name, centre number and candidate number on every printout and in the evidence document.
Save and name files exactly as asked.
Use the last 15 minutes for the final check routine.

!Watch out

Phones and smartwatches must be handed in before you enter the room. Having one on you can lead to disqualification.

4.2 Network issues and communication

Security of data transfer

Data on a network can be intercepted, changed or stolen. Networks also spread malware quickly.

Authentication means proving that a user is who they say they are, before they get access.

Common protections: user IDs and passwords, firewalls, encryption of data being sent, and anti-malware software.

Strong and weak passwords

A weak password is short or easy to guess: a name, a birthday, a word from the dictionary, `123456` or `password`.

A strong password is long and mixes upper-case letters, lower-case letters, numbers and symbols. It is not a real word and is not linked to the user.

Each extra character multiplies the number of possible passwords. So length matters most. Type passwords into the checker and watch the time to crack change.

e.g.Example

Assume an attacker's computer tries 10 billion guesses a second. 8 lower-case letters: 26^8 = about 209 billion options. Cracked in about 21 seconds. 8 characters from all 95 keyboard characters (including the space): 95^8 = about 6.6 × 10^15. About 8 days. 12 characters from all 95: 95^12 = about 5.4 × 10^23. About 1.7 million years.

!Watch out

A strong password is still unsafe if it is reused on many sites, written on a sticky note, or never changed after a data breach.

There is something to try for this step in the IGCSE library.

Passwords and biometrics

Passwords are the most common method. They are cheap and easy, but can be guessed, forgotten, seen by shoulder surfing or stolen by spyware.

Biometrics use a unique part of a person's body or behaviour: fingerprint, face, iris or retina, voice or handwriting.

Biometric	Advantage	Disadvantage
Fingerprint	Quick and cheap; unique to each person	Dirty or cut fingers may not be recognised
Face recognition	No contact needed	Lighting, glasses, beards or ageing can cause errors
Iris / retina scan	Very accurate and very hard to fake	Expensive; retina scanning is intrusive
Voice recognition	Works over the phone; no extra hardware on a phone	Colds and background noise cause errors; can be recorded and replayed

?Why?

Biometrics are more secure than passwords because a body feature cannot be forgotten, shared or easily guessed.

Cards and tokens

A magnetic stripe card holds data such as a staff ID on its stripe. It is swiped to open doors. Cheap, but easy to copy and damaged by magnets.

A smart card has a chip that stores and processes data, often with an RFID antenna. It is harder to copy and can hold more data. Often used with a PIN.

A physical token is a small device that shows a one-time password (OTP). Some need the user's PIN first. Banks use them for online banking.

An electronic token is software, usually an app on a phone, that creates a one-time code or approves a log-in. Codes change every 30 to 60 seconds, so a stolen code is soon useless.

e.g.Example

Logging in to online banking: 1. Type user ID and password (something you know). 2. Open the bank's app, which shows a 6-digit code that changes every 30 seconds (something you have). 3. Type the code. Two different factors make it much harder for a hacker.

!Watch out

A token's code is a one-time password. Say why it helps: even if it is intercepted, it cannot be used again.

Zero login

Zero login is a way of authenticating without typing anything. The system recognises the user from biometrics and behaviour, such as how they hold the phone, how they type and where they usually are.

Advantage: very convenient, and nothing to forget.

Disadvantage: the system collects lots of personal data, users may not know they are being tracked, and it is harder to tell how secure it is.

Anti-malware

Malware is software designed to harm a computer or steal data, such as viruses, spyware and ransomware.

Anti-malware software (including anti-virus) scans files and emails, compares them with a database of known malware signatures, and watches for suspicious behaviour.

Infected files are quarantined (isolated so they cannot run) or deleted. The software must be updated regularly so it knows about new malware.

?Why?

On a network, one infected computer can infect all the others, so every device needs up-to-date anti-malware.

Electronic conferencing

Video conferencing uses webcams, microphones, speakers and screens so people in different places can see and hear each other live.

Audio conferencing uses only sound: a phone call with three or more people, or an internet call with no video. Participants often dial a number and type a PIN.

Web conferencing (webinars) runs in a browser or app. As well as video and audio, users can share screens, chat by text, use a whiteboard and vote.

Advantages (all types)	Disadvantages (all types)
No travel, so saves time, money and fuel	Needs a reliable, fast internet connection; lag and dropped calls
Meetings can be set up at short notice	Time zones make scheduling hard for international meetings
People can join from anywhere, including when ill or abroad	Less personal: body language is harder to read
Safer: no travel risks	Equipment costs (webcams, headsets, software licences); security risk if calls are hacked

e.g.Example

Audio conferencing is cheaper and needs less bandwidth than video, but people cannot see slides or faces. Web conferencing lets a teacher share a presentation and run a poll, which audio-only cannot do.

6.10 Recognition systems

Automatic number plate recognition (ANPR)

ANPR reads car number plates from camera images. It is used in car parks, speed and average-speed cameras, toll roads and low-emission zones.

Advantages	Disadvantages
No tickets to lose; barriers open automatically	Dirty, damaged or fake plates are misread
Helps police find stolen cars and enforce traffic laws	Privacy worries: cars and people can be tracked
Fewer staff needed in car parks	Expensive cameras and software

e.g.Example

Entering a car park: 1. A sensor detects the car and triggers the camera. 2. The camera takes a photo of the front of the car (infrared light is used at night). 3. Software finds the number plate in the image. 4. Each character is separated and read using OCR. 5. The plate number is stored with the date and time. 6. On leaving, the plate is read again and the fee is calculated from the time difference.

OMR, OCR, RFID, NFC and biometrics

OMR reads marks in set positions: multiple-choice exam sheets, school registers, lottery tickets, questionnaires. OCR turns scanned text into editable text: passports at airport gates, digitising books, scanning forms.

RFID uses radio waves to read tags without contact or line of sight. Uses: tracking parcels and stock, livestock tags, library books, metro cards, contactless cards, passports. Passive tags have no battery and are powered by the reader. Active tags have a battery and can be read from far away.

NFC is a short-range type of RFID (under about 4 cm). Uses: phone payments, sharing data between two phones, tapping a tag for information.

Biometric recognition identifies people by fingerprints, face, iris, retina or voice. Uses: unlocking phones, airport e-gates, school registers, entry to secure rooms.

System	Advantage	Disadvantage
OMR	Thousands of forms read fast and accurately	Forms must be printed precisely; unclear marks are misread
OCR	Saves retyping; text becomes editable and searchable	Errors with handwriting or damaged print, so output must be checked
RFID	Reads many tags at once, through packaging, very fast	Tags can be read or copied by others; more expensive than barcodes
NFC	Very short range makes accidental reading unlikely; built into phones	Range is tiny; phone battery must have charge
Biometrics	Unique to the person; cannot be forgotten or lent	Expensive; errors from injuries or lighting; privacy concerns about storing body data

7.4 Implementation

Four ways to change over

Implementation means putting the new system into use. Staff are trained and data from the old system is transferred.

Direct changeover: the old system stops and the new one starts at once, for example over a weekend.

Parallel running: the old and new systems both run at the same time, until the new one is trusted.

Pilot running: the new system is used in one branch or department first. Once it works, it goes to the rest.

Phased implementation: the new system is brought in one part at a time, across the whole organisation.

e.g.Example

A chain of 40 supermarkets gets a new till system. Direct: all 40 shops switch on Monday morning. Parallel: every shop runs old and new tills side by side for a month. Pilot: one shop in Getafe uses it first, then the other 39. Phased: all shops get the new payments part first, then stock control a month later.

!Watch out

Pilot and phased are easy to mix up. Pilot = one place, whole system. Phased = whole organisation, one part at a time.

Advantages and disadvantages

Each method trades cost and speed against risk.

The key question: what happens if the new system fails?

Method	Advantages	Disadvantages
Direct	Cheapest: only one system runs and staff do the work once. Benefits are immediate. Fastest.	Highest risk: if the new system fails, there is no backup and work stops. Data could be lost. Staff must be fully trained before the switch.
Parallel	Lowest risk: if the new system fails, the old one is still working. Results can be compared to check the new system.	Most expensive: staff do every job twice, so extra staff or overtime are needed. Takes longest. Data entered twice can lead to errors.
Pilot	If it fails, only one branch is affected. Staff in the pilot branch can train others. Cheaper than parallel.	Slow to reach the whole organisation. If the pilot branch fails, it suffers on its own. The pilot branch may not be typical of the others.
Phased	If one part fails, only that part is affected and it can be fixed. Staff learn one part at a time.	Slow: takes a long time to fully implement. Parts of old and new systems must work together, which is hard. Costly to evaluate each phase.

?Why?

There is no best method. The right one depends on how bad a failure would be, how much money there is, and whether the system can be split into branches or parts.

Choosing the right method

Use direct when the system is small, simple, or the old system has already stopped working. Also when two systems cannot run side by side.

Use parallel when failure would be serious, such as payroll, banking or hospital records.

Use pilot when the organisation has many similar branches, such as shops or banks.

Use phased when the system splits into separate parts, such as a school system with attendance, marks and timetable modules.

e.g.Example

Try the toy. For each scenario, pick a method and read why. Scenario: a hospital moves patient records to a new system. Best answer: parallel running. A failure could put patients at risk, so the old system must keep working until the new one is proven.

!Watch out

In a 'choose and justify' question, the justification must link to the scenario. 'Parallel is safest' is weak. 'Parallel, because if the new payroll fails, 300 staff still get paid by the old system' is strong.

There is something to try for this step in the IGCSE library.

Study it

Open the study page and go one step at a time.

ICT topic 1

Check yourself

One question at a time. The reason shows after each answer.

Saved on this device.

Last Paper 1 practice

You will learn to

Success criteria

The day before

In the exam room

Security of data transfer

Strong and weak passwords

Passwords and biometrics

Cards and tokens

Zero login

Anti-malware

Electronic conferencing

Automatic number plate recognition (ANPR)

OMR, OCR, RFID, NFC and biometrics

Four ways to change over

Advantages and disadvantages

Choosing the right method

Types and components of computer systems

Input and output devices

Storage devices and media

Networks and the effects of using them

The effects of using IT

ICT applications

The systems life cycle

Safety and security

Audience

Communication

File management

Images

Layout

Styles

Proofing

Graphs and charts

Document production

Databases

Presentations

Spreadsheets

Website authoring