Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

1 Types and components of computer systems

Answers to exercises
1a For example: hi-fi, television, microwave ovens, ovens, toaster, fridge/freezer, washing
machine, dish washer, and so on.
Advantages:
• They can operate remotely
• They can operate some devices while doing something else.
Disadvantages:
• hacking
• viruses.
Answers to exam-style questions
Answers to questions 1, 2, 3, and 4 in this section are example answers for past paper questions. The details
of the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a PC or desktop
b laptop
c tablet
d smartphone
2 CLI GUI
() ()
Instructions have to be typed in 
Applications are represented by icons 
Options are chosen from a menu 
Many instructions have to be memorised 

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

3 • PCs/laptops are needed for applications which require high speed processing.
• PCs/laptops are needed for applications which require greater internal memory capacity.
• PCs/laptops are needed for applications which require greater backing storage capacity.
• PCs/laptops are needed for applications which require larger screens.
• PCs/laptops are needed for applications which require more manageable keyboards.
• PCs/laptops are needed for applications which require easy navigation from screen
to screen.
• PCs/laptops are have access to a wider range of application software.
• PCs/laptops are still needed to carry out complex mathematical functions.
• It is easier to monitor the use of PCs/laptops.

4 • Post-WIMP GUI allows use of pinching, scrolling, expanding.

• Post-WIMP allows use of touch screen but CLI does not allow for this.
• GUI Icons speed up finding instructions; with CLI you have to type out commands in full.
• It is difficult to edit CLI.
• If a mistake is made in CLI it could have major consequences, whereas GUI has
less impact.
• Due to graphics, GUI uses a lot of memory/CLI is a smaller program.
• Loss of memory in GUI slows down computer performance.
• GUI cannot operate properly if memory is low.
• Loss of memory affects the kinds of applications that can be run (using GUI).
• GUI is more user-friendly; with CLI user needs to remember commands.
• GUI has more varied use on other devices, not just on computers.
• In a CLI, several commands have to be typed in rather than one single command as in GUI.
• CLI commands have to be typed in every time the same command/operation is run.
• GUI sometimes has a CLI embedded in it.
• CLI and GUI both carry out file management.
• CLI and GUI use similar utility programs.
• Both CLI and GUI use operating systems.
• Both CLI and GUI control the hardware and software.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 2

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

5 RAM ROM
() ()

Data on a chip is stored permanently and cannot be deleted 

It is not possible to alter or delete the data stored on the chip 

Data on the chip is stored temporarily and can be deleted by the user 

Data is retained even when the computer is powered down 

Stores data, files or part of the operating system which is currently in use 

Data is lost when power to the computer is turned off 

It contains the basic input/output system used to boot up the computer


when it is first powered up

It is a form of volatile memory 

It is a form of non-volatile memory 

6 a AR:
• The user experiences the relationship between the virtual and the real world.
• Virtual information and objects are overlaid onto a real-world situation.
• The user can experience the AR world through goggles or smartphone screens.
VR:
• It has the ability to take the user out of the real world and into the virtual world.
• The user is fully immersed into a simulated digital world.
• The user must wear a VR headset/head-mounted display.

b • military: training and operations

• education: for example, looking inside a pyramid
• healthcare: diagnostic tool
• entertainment: enhance by giving realism and interaction
• fashion: see how you look using AR and the camera in a smartphone
• business: training and role-playing scenarios
• engineering: how a building will look before it is built
• sport: for example, a golfer perfecting their swing.

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

Cambridge IGCSE Information and Communication Technology Teacher's Guide 4

© Graham Brown and David Watson 2021
Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

2 Input and output devices

Answers to exercises
2a For example:
Industrial process (sensor input, control/monitor output)
Advantages:
• better/faster control than humans
• do not forget to take readings
• safer.
Disadvantages:
• more expensive
• deskilling
• security issues.
Game console (controls by gamer, sound/screen outputs)
Advantages:
• more realistic
• more interesting games
• can save status.
Disadvantages:
• people can become ‘hooked’
• online games pose problems for teenagers.
Word processor (keyboard input, printer or monitor output)
Advantages:
• easier to make corrections
• can save/alter/paste/etc.
Disadvantages:
• skills, such as spelling, are lost.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 1

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

Answers to exam-style questions

Answers to questions 2, 8 and 9 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a inkjet printer, one from:

• small number of high-quality documents
• photographs.
3D printer, one from:
• physical prototypes (CAD/CAM)
• physical models (from blueprints)
• medical applications (prosthetics, drugs, etc.).
b EITHER laser printer, plus one from:
• uses toner/powdered ink
• uses positive/negative charged drums
• no moving head
• faster printing
• high volume possible.
OR dot matrix printer, plus one from:
• impact printer
• head (matrix of pins) strikes a coloured or black ribbon
• very slow and low-quality printing
• cannot print quality graphics or photos
• can use continuous stationery
• can make carbon copies
• capable of working in damp, dusty or dirty atmospheres.
2 Three from:
• cards can be read accidentally
• only small amounts (up to around $50) can be withdrawn at a time
• more chance of fraud if a card is lost or stolen
• not everyone will have a contactless card
• devices can read cards wirelessly and steal money.

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

3 a (c) keyboard
b (d) scanner
c (a) reading barcodes
d (e) dot matrix printer
e (a) (graph) plotter
f (b) laser printer
g (c) heat
h (a) CRT monitor
i (e) mouse
j (e) (graph) plotter
4

5 a QR code
b OMR
c sensor
d microphone
e scanner
f remote control
g RFID reader
h laser printer
i dot matrix printer
j mouse

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6 a i • The camera in a smartphone or tablet is used to capture an image of the QR code.

• An app in a smartphone/tablet interprets the QR code.
• If it is a web address, browser software automatically reads data generated by
the app.
ii • advertising (email addresses, website addresses, phone numbers, etc.)
• links to apps to allow easy downloads
• Wi-Fi authentication
• augmented reality (position and objects in VR world)
• virtual online stores.
b Advantages, two from:
• holds more information than barcodes
• fewer errors than with barcodes (QR codes have built-in error-checking systems)
• easier to read (do not need expensive laser or LED scanners, unlike barcodes)
• easier to transmit QR codes as text or image
• can encrypt QR codes.
Disadvantages, two from:
• more than one QR format is available
• can be used to transmit malicious codes (known as attagging)
• anyone can generate QR codes using many free apps.
c When an item from the screen is selected by touching it, this is the touch screen acting
as an input device. The result of selection can produce another page which is shown on the
screen, therefore it is now acting as an output device.
7 a Keyboard – input data into a spreadsheet or word processor
b Driving wheel – used in simulators; joystick – used in video/computer games
c QR code reader – advertising websites or a company website
d Barcode reader – used in supermarkets to hold details of items
e Microphone – intruder alarm system; voice activation (for example, in cars)
f Touch screen – selections from a menu
g 3D printer – for example, producing solid objects during development, prosthetics and for
medical uses
h Dot matrix printer – in pay slips where continuous stationery and carbon copies are needed
i RFID – for example, livestock or packet tracking, passports or admission passes at
a theme park
j Chip and PIN reader – payments at a restaurant (for example, where PIN needs to be typed
in to match the one stored on the chip in the card)

Cambridge IGCSE Information and Communication Technology Teacher's Guide 4

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

8 ()
Pressure sensor 
Oxygen level sensor
Wind speed sensor
Sound sensor 
Body sensor
Moisture sensor
Infrared sensor 
Touch sensor

9 a Device

Data from the starting pistol is read by this device sound sensor
This device detects that the athlete has left the starting block pressure sensor
When the light beam is broken the data is read by this device infrared sensor
b Digital camera (or camera card reader) connected to the computer as an input, to transfer
the camera's image files to the computer for storage and use. Printed photographs put
through a scanner that is connected to computer as an input device, to create digital image
files to be stored and used.
10 True False
() ()
Answers to multiple-choice examination papers can be read

using an optical mark reader (OMR)

The PIN is stored on the magnetic stripe on a credit card 

The chip on a credit card is read by a PIN reader 

An RFID chip can be used to track stock 

Cambridge IGCSE Information and Communication Technology Teacher's Guide 5

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

3 Storage devices and media

Answers to exercises
3a a CD-ROM, DVD-ROM, Blu-ray
b CD-RW, DVD-RW, Blu-ray
c Blu-ray
d CD-R, DVD-R
e CD-RW, DVD-RW, Blu-ray

Answers to exam-style questions

Answers to question 1 in this section are example answers for past paper questions. The details of the
relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 CD DVD Blu-ray
() () ()

Stores lower quality audio files 

Has the highest storage capacity 

The RAM version of this medium is used to record and


play recorded images at the same time

Stores high definition movies 

2 Optical Magnetic Solid state

() () ()

SSD 

Blu-ray 

Pen Drive 

Portable hard disk drive 

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3 a Optical media:
• relies on optical/light properties of laser light
• laser is used to read/write data on disk
• data is stored in lands and pits
• uses red or blue laser light.
b Four from:
• SSD more reliable since there are no moving parts
• SSD considerably lighter in weight
• SSD does not need to ‘get up to speed’ to work
• SSD lower power consumption therefore it runs cooler
• SSD very thin because there are no moving parts
• SSD data access time is 100 times faster
• SSD data read speed is much faster.
4

Cambridge IGCSE Information and Communication Technology Teacher's Guide 2

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5 • direct access
• media
• platters
• latency
• data transfer rate
• data access time
• Blu-ray discs
• three-year period
• SSD endurance
• memory sticks

6 True False
Statements
() ()

Both DVDs and Blu-ray discs can make use of dual-layering technology 

CD-RW can act as the same as a ROM chip 

Solid state drives wear out very quickly due to rapid electron movements

in the transistors that make up the memory matrix
Cloud storage makes use of Blu-ray discs to store customers' music and

photo files

Platters on an HDD can be recorded on both the bottom and top surface 

HDDs suffers from latency due to the time taken for a specific block of

data on a data track to rotate around to the read-write head

Magnetic tapes make use of serial data access 

The data transfer rate is the time taken to locate data on an HDD platter 

The areas on a DVD where 1s and 0s are stored are called pits and lands 

A memory stick is another name for a flash drive 

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7 a i Three from:
• Blu-ray uses blue laser light/DVD uses red laser light
• Blu-ray has a much larger storage capacity
• Blu-ray has a secure encryption system built in
• Blu-ray track pitch 0.3 µm compared to 0.74 µm.
ii Blu-ray – high definition movies/back-up hard devices, DVD – CCTV
systems/recording TV programmes.
b i Three from:
• SSDs have no moving parts
• SSDs have low power consumption
• SSDs have limited endurance
• SSDs are lightweight and thin
• HDDs use rotating disks and read/write heads
• HDD have high power consumption
• HDDs suffer from latency
• HDDs can undertake a greater number of read/write operations.
ii HDDs are used as cloud severs and back-up devices. SSDs are used in smartphones
and tablets as the main memory.
8 a • use of cloud storage replacing users' own HDDs and SSDs
• SSD is more reliable (no moving parts)
• SSDs have lower power consumption (less heat generated) than HDDs
• SSDs are much lighter and thinner (allowed development of laptops, tablets
and smartphones)
• SSDs have a much faster data access time than HDDs
b • Technologies which do not need to get up to speed allow instant access
• use of MP3 format replacing audio CDs
• streaming is replacing the need for CDs/DVDs/Blu-ray disks
• development of memory sticks replacing CDs and DVDs.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 4

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

4 Networks and the effects of using them

Answers to exercises
4a Student needs to print out result of running ‘tracert’.
4b i 25-May-2020 – weak; dates are not good passwords
ii Pas5word – weak; one of the top ten passwords used
iii ChapTer@15 – strong; upper and lower case + numbers + other characters
iv AbC*N55! – strong; upper and lower case + numbers + other characters
v 12345X – weak: easy to guess password

Answers to exam-style questions

Answers to question 1 in this section are example answers for past paper questions. The details of the
relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a Three from:
• video camera/webcam
• microphone
• keyboard
• large screen/monitor/data projector
• speakers/headphones.
b A web conference:
• is held over the internet using TCP/IP connection/in real time, for example,
webinar/webcasts/VoIP
• can be point to point (VoIP) or multicast (i.e. source data is sent from one computer to
many different receiving computers)
• allows text communication
• allows video communication
• uses web browsers.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 1

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2 Bluetooth – data transfer rate of 3.1 Mbytes/second

WiFi – data transfer rate of 31 Mbytes/second
Bluetooth – effective range of ~30m
WiFi – effective range of ~100m
Bluetooth – maximum number of connected devices is 7
WiFi – infinite (depends on router used)
Bluetooth – key matching encryption security
WiFi – WEP and WPA security
3 a • hub and switch both used to connect devices to form a LAN
• both use data packets
• switch is a type of hub
• both check/read data packets
• in a hub, data packet sent to every device on a LAN
• in a switch, data packet sent to a specific device
• security is lower in a hub as all data is broadcast
• in a switch, the destination address is looked up before data is sent
• in a hub, all data packets are sent to all devices
• a switch uses a MAC address to locate the destination device.
b a bridge:
• connects LANs together
• scans for a device’s MAC address
• sends data out using data packets
• connects networks together that use the same protocols
• does not make use of routing tables
• only has two ports.

c • data packets are sent from the computer in network ‘A’ to the nearest router
• the router checks IP address and notes the data packets that aren’t intended for any
devices on network ‘A’
• data packets are forwarded to other routers in network
• data packets are forwarded to the router linked to network ‘B’ using its IP address
• the router recognises the IP addresses of data packets referred to network ‘B’
• data packets are forwarded to the destination computer on network ‘B’.

d • bridges only connect LANs using the same protocols

• routers can connect networks using different protocols
• routers can join LANs over the internet
• bridges only have two ports but routers have more than two.

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4 a Zero login:
• allows users to log into a computer system without the need to type in a password
• relies on biometrics …
• … and on behavioural patterns …
• biometrics: fingerprints, facial recognition
• behavioural: typing speed, location, how the user swipes the screen
• the systems use the above information to build up complex user profiles.
b Physical token:
• a type of hardware security device
• form of authentication …
• … to prove user has possession of the token
• when the PIN is entered into token, a one-time password (OTP) is created and shown
on screen
• the code changes every 30 sec or so
• the OTP is typed into another device as part of a security authentication process
• can be connected or disconnected (for example, through USB).
c Electronic token:
• software installed on user's device as an app
• used to authenticate a user
• the user opens the app on a device which generates random numbers (OTP) …
• … which is valid for a limited amount of time
• the user enters the OTP onto the website using this type of authentication; often
includes a PIN, touch ID or face ID in addition
• the website server runs the same app
• both the user and the website use synchronised clocks and therefore generate the
same OTP.

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5 Router Switch Hub

Feature
() () ()
Used to connect devices together to form a local area
 
network (LAN)
The destination MAC address is looked up before the data

packet is sent to the correct device

Used to connect LANs to other, external networks 

Uses both MAC and IP addresses to enable data packets to


be sent to the correct device on another network

All data packets are sent to all the devices on the network 

Data packets are sent only to a specific device on the same


network

6 a Virus – a program which replicates; the intention is to delete, corrupt or alter files/data to
prevent normal running of a computer.
b Three from:
• checks software or files before they are run or loaded onto a computer
• compares a potential virus against database of known viruses
• carries out heuristic checking (checking on behaviour of a program/file that could
indicate it is a virus)
• puts infected files or programs into quarantine
• automatically deletes the virus or allows the user to make the decision
• runs in the background

7 a • a magnetic stripe card is swiped through a reader.

• data, such as name, ID, sex, date of birth will be read
• might also request other authentication such as PIN, finger ID, face ID
• scanned data matched with data stored on a database
• if they match, entry is permitted.

b • require use of PIN, for example

• include a chip making them contactless, a chip can contain data such as PIN or
biometric data
• use holographic image on cards to stop photocopying
• photographic image of user printed on cards; this could also be stored on the chip to
prevent fraudulent use.

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9 a Cloud computing:
• computing resources that can be accessed on separate and remote servers
• cloud computing can refer to storage or applications
• may be hundreds of servers in several locations
• the same data is stored on more than one database in case of maintenance and/or repair
(data redundancy)
• three types of cloud storage: public, private, hybrid.
b Three from:
• files can be accessed at any time, in any location, on any device
• there is no need to carry external storage with you; not even necessary to take a
computer containing files with you
• the cloud provides users with remote, automatic back-up
• the cloud allows recovery of data if the customer’s hard drive fails on their
own computer
• it offers unlimited storage capacity.

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c Three from:
• it is not always secure
• if there is a poor internet connection, or none, the cloud cannot be used
• it can be expensive if large amounts of storage needed
• the potential failure of cloud storage companies is always possible; poses risk of losing
all back-up data.
10 a "A" = hub
b "B" = hub/switch, "C" = hub/switch, "D" = bridge
c "E" = hub/switch, "F" = router

Cambridge IGCSE Information and Communication Technology Teacher's Guide 6

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

5 The effects of using IT

Answers to exam-style questions
Answers to questions 1 and 2 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a Three from:
• people do not have to do manual tasks anymore
• gives people more time for leisure, hobbies or socialising
• no need to stay at home to do cooking, washing clothes
• devices can be controlled from a smartphone or tablet remotely
• automated burglar alarms give a sense of security
• smart fridges/freezers lead to a healthier lifestyle
• devices are more energy efficient
• easier to ‘program’ devices to do a number of tasks.
b Three from:
• can lead to unhealthy lifestyles due to reliance on ready-made meals
• tend to make people lazy due to machine dependence
• people become less fit since devices do all the work
• loss of household skills
• cybersecurity risks
• wasteful since devices are thrown away when it breaks down
• can be more complex to operate
• leaving devices on stand-by is wasteful of energy.

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2 Neck/back strain:
• use fully adjustable chairs and tilting screens
• can be difficult to get a comfortable position if there are too many adjustments.
RSI:
• correct posture using adjustable chairs
• take regular breaks and exercise
• use voice-activated software and ergonomic keyboards
• voice-activated software can annoy others
• voice-activated software is expensive but can remove many RSI risks
• regular breaks do not cost money, but exercise needs to be the correct type.
Eyestrain:
• take regular breaks and exercise
• use anti-glare screens
• have eyes tested on regular basis
• anti-glare screens only work if other factors are correct (for example, correct lighting)
• glasses on their own will not be totally effective
• eye tests can also help with neck strain since it is easier to read the screen.
Headaches: see notes above on eyestrain
Ozone irritation:
• poor ventilation in the room
• need for a dedicated printer room
• use inkjet printers instead
• only works if the printer room is properly ventilated
• using a dedicated room avoids the need to change the printers.
3 a Potential security issues:
• potential virus risks
• hacking into devices which are remotely controlled
• if not password-protected this might allow a criminal to gain personal data
(for example, a central heating system might contain holiday dates)
• if a fridge/freezer automatically orders food, it is possible to gain credit card details
• important to password protect every device if possible.

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b True False
() ()
Using microprocessors has increased the longevity of devices in

the home, therefore reducing waste

Microprocessor-controlled devices are far more energy efficient 

Smart televisions are an example of a labour-saving device 

Microprocessor-controlled devices in the home are not vulnerable


to attack by viruses or hackers
Microprocessor-controlled devices, such as smartphones, have no

impact on social interactions

5 a Advantages:
• if there is accident or traffic congestion, smart signs can keep traffic moving …
• … or warn traffic to leave the road
• improved safety since traffic can be warned in advance of adverse weather or an
accident
• can give helpful information such as time to next junction.
b Risks:
• hacking or virus
• if system is ‘taken over’ then there are potential safety risks.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 3

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

6 ICT applications
Answers to exercises
6a Answers with student explanation of how the feature is to be used:
• search and replace
• margins
• cut and paste
• import
• spellchecker
• drawing
• type fonts/size
• tables.
6b Posters printed out by the student.
6c Advantages with student explanation:
• no need to buy physical copies of books
• no need for customers to carry heavy books around with them
• can read anywhere
• easy to page mark
• easier to use text in customers' documents.
Disadvantages with student explanation:
• sometimes harder to read than a book
• devices are not cheap to buy
• no physical object to own.
6d Spreadsheet produced and printed out; makes use of graphics.
6e Pilot training – Easier/safer to make changes to a model
Environmental modelling – Takes too long to get results back from the real thing
Simulating bridge loading – Cost of building the real thing is too expensive
Nuclear reactor model – Some situations are too dangerous for humans
Space exploration – It is almost impossible to do the tasks for real

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6f Examples:
• bottling plant
• canning plant
• car production
• television production
• clothing manufacturing.
Look for functions such as:
• filling bottles/filling cans
• labelling
• fitting caps/welding cans
• spraying bodies/panels
• fitting windscreens
• weld body shell
• fit screen into surroundings
• fit electronic components
• control linking of fibres and so on.
Look for advantages such as:
• faster operations
• greater productivity (the production can run 24 hours a day, every day)
• greater consistency
• built-in quality control
• reduced cost to the consumer.
Look for disadvantages such as:
• deskilled workforce
• expensive to set up
• any changes to designs or process need human to intervene, reprogram, etc.
6g • days selected
• flight lines selected
• destination + departure airports selected
• number of passengers input
• credit/debit card details input
• passenger information provided
• one seat allocated, removed (flagged) on database to stop double-booking
• ticket sent as QR code.

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6h 1 Advantages:
• most efficient route
• more deliveries per day
• faster way/service.
2 Disadvantages:
• cannot always take roadworks into account
• expensive software
• sometimes the most logical route is not the fastest.
6i Sequence: A, D, C, E, G, J, distance: 49 km
6j 1 For example: a Identification of chemical
• gather identification techniques from chemists and sources such as the internet/books
• this data is entered into a knowledge base …
• … in the form of objects and attributes
• … for example, object: sodium chloride
• attribute: yellow flame test
• attribute: white precipitate with silver chloride
• rules base is also created containing inference rules
• for example, if flame test = yellow THEN it contains sodium, etc.
• develop the user interface as a series of Yes/No questions
• for example, is the chemical white in colour? Yes/No
• finally, the system is tested with data with a known outcome so that the performance of
the expert system can be judged.
2 For example: 2b identify an 'unknown' chemical compound

Object Flame Add silver Add barium Solution

Test nitrate nitrate colour

Sodium chloride Yellow White ppt No change Colourless

Copper sulphate Blue No change White ppt Blue
Potassium chromate Lilac Blood red ppt Yellow ppt Yellow/orange

• Is the colour change yellow? NO

• Is the flame test yellow? NO
• Is there a precipitate with silver nitrate? NO
• Is there a precipitate with barium nitrate? YES
• Is the precipitate colour white? YES
• Conclusion: The chemical found is copper sulphate

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6k 1 knowledge base
2 explanation system
3 expert system shell
4 rules base
6l 1 Article printed out showing pros and cons of shopping online.
2 Examples: supermarkets, libraries, luggage handling at airport. Could use RFID tags in
some applications. Barcodes are still widely used because they are simple, widespread and
cheaper than other systems such as RFID.
6m • car number plate read by camera
• OCR software identifies characters on number plate
• allows speeding cars to be identified
• allows car routes to be monitored
• allows lanes to be closed or opened to improve traffic flow.
Answers to exam-style questions
Answers to questions 2, 4, 5 and 7 in this section are example answers for past paper questions. The details
of the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a • cameras take an image of number plate/front of vehicle

• the image is saved
• software determines where on the image the number plate is
• converts number plate to text …
• … conversion by OCR to produce text file
• sends a text file
• compares the text with data stored on a database
• confirms that the driver is authorised.

b • both use direct data entry systems

• both are used to communicate with a reader
• RFID chips can be read from a greater distance than barcodes
• barcodes need to be in line of sight with the reader
• RFID chips can be uploaded more easily
• RFID chips can be read at a faster rate
• RFID chips are more robust
• RFID chips are more secure/harder to forge.

c • point a smartphone or tablet camera at the QR code

• use a QR app to access the camera on the phone/tablet
• a QR image is taken and software (in app) interprets the QR code
• the information in the QR code then displays on the device, or sends user to a website
containing more data.

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d i NFC = near field communication:

• uses RFID technology
• chips are passive (no power).
ii this is peer-to-peer; the mobile phone is held close to a reading device
• NFC reader (up to 5 cm)
• when payment has been initiated, NFC device and smartphone pass encrypted data
back and forth to each other
• all communications are encrypted
• encrypting is dynamic (changes with every transaction)
• makes use of tokenisation.
2 a • open a word processor
• take photos/search for images
• upload images from a camera/HDD/CD-ROM/memory card
• scan the photos from archive material
• save the photos to file
• open the text files
• import the photos into the document
• copy/edit/resize the photos
• import previously saved text
• position/place the photos
• wrap the text
• proofread the document
• save the completed document.

b • the language/dialect used in checking spelling could be different (for example,

English – UK/USA)
• names/proper nouns might be highlighted in error but are acceptable if no suggestion is
given (for example, where, were, wear)
• a spell checker may not understand the word if it is badly spelt
• the word may not exist in the spell checker dictionary/dictionary may not be up to date.
3 a Three from:
• safer, as humans could be injured by rock falls
• easier to replace a robot rather than trained miner
• robots do not require wages so they can be cheaper over time
• robots can work continuously
• robots can work in hazardous conditions
• robots may be more productive.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 5

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b Two from:
• any changes needed to mining equipment/rock type requires reprogramming of
the system
• reprogramming takes time
• reprogramming can increase the cost
• setting up the robot in the mine will be dangerous for humans
• expensive to maintain/repair
• the initial cost of a robot is high.
4 a • the washing machine sends out a radio signal to read the data from the RFID
• RFIDs act as passive transponders
• clothing has a battery attached to the RFID
• a radio signal given out by the chip is read by the receiver using its antenna.

b • stops material being incorrectly washed

• stops coloured items of clothing being in the wrong wash
• stops clothing of different material being washed with others
• allows the wash cycle to be set automatically
• washing machine will know the amount of water to use, so will not waste water.
5 a Three from:
• cheaper than building the real thing
• quicker to see results rather than physically building it
• safer than building the real thing
• easier to change variables in a model
• can use ‘what if’ scenarios.
b • sensors out in the bay initiate a faster response to flooding
• safer as flood watchers are not put in danger from rising water
• data collected is more accurate – data collection is continuous
• data readings can be taken more frequently
• people in the city can be alerted faster to danger
• predictions can be made from data more easily.
c • microprocessor reads data from sensors
• microprocessor has a set of pre-stored values
• microprocessor compares readings from sensors with pre-set values
• … if higher, the microprocessor sends signals to the actuator to close the barrier
• … if lower, the microprocessor sends signals to the actuator to open the barrier.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 6

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6 Four from:
• speeds up booking process
• no need for customer to travel to theatre, saving them travelling time
• no queuing
• reduces postage cost
• can amend booking at any time
• can book several shows
• no double-booking
• can book from anywhere, at any time.
7 Advantages:
• can ‘bank on the move’ therefore no need to visit a bank
• less physical money therefore safer
• available 24/7
• available anywhere in the world
• no need to go to the bank therefore saves money
• no need to go to the bank therefore saves time.
Disadvantages:
• fewer branches are available to customers
• non-IT literate users, or those that do not have internet access, are left out
• need to buy a computer
• chance of bank fraud
• physical money cannot be withdrawn/deposited
• easier to mismanage account.
• It is easier to make errors with online banking and transfer money incorrectly to
different accounts.
8 Advantages of internet shopping:
• There is no longer a need to travel into the town centre, thus reducing costs (money for
fuel, bus fares, etc.) and saving time; it also helps to reduce town centre congestion and
pollution.
• Users now have access to a worldwide market and can thus look for products that are
cheaper; this is obviously less expensive and less time consuming than having to shop
around by the more conventional methods; they will also have access to a much wider
choice of goods.
• Elderly people and people with disabilities can now access shops without the need to leave
home, which can be of great benefit.
• Because it is online, shopping can be done at any time on any day of the week (i.e. 24/7,
which is the term now used) – this is particularly helpful to people who work during the
day, as the shops may normally be closed when they finished work.

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• People can spend more time doing other things, for example, going shopping to the
supermarket probably took up a lot of time; by doing this online (for example, setting up
repeat items) people are now free to do more leisure activities.
• There are often long queues at checkouts at the shops, so internet shopping saves time.
• The shops save money by not having as many staff working for them (reduced wage bill)
or hiring of high-street premises (reduction in rental costs) – these savings are often passed
on to the customer in the form of cheaper goods.
Disadvantages of internet shopping:
• There is the possibility of isolation and lack of socialisation if people stay at home to do all
their shopping.
• There are possible health risks associated with internet shopping because of lack of
exercise; if people physically go shopping then they are getting some exercise.
• Security issues are a major concern (for example, hacking, stealing credit card details, etc.)
as are viruses and other malware (for example, phishing, pharming and so on).
• Accidentally using fraudulent shopping websites is always a risk and this is linked to
security issues.
• It is necessary to have a computer and to pay for the internet to take part in online
shopping.
• Unlike high-street shopping, it is only possible to see a picture of the goods, which might
not portray the exact colour; you cannot try on an item of clothing to see if it fits before
buying it; you also have to wait several days for the goods to arrive; returning goods can
also be expensive.
• High-street shops are closing because of the increase in internet shopping and this is
leading to 'ghost towns' forming.
Effects on companies due to the spread of internet shopping:
Advantages
• Companies can save costs here because fewer staff need to be paid and it is not necessary
to have as many shops in high streets to deal with potential customers.
• Because the internet is global, the potential customer base is increased.
Disadvantages
• There will be some increased costs, however, because of the need to retrain staff and the
need to employ more staff in despatch departments.
• There are also costs due to the setting up and maintaining of websites to enable internet
shopping.
• Because there is very little or no customer-employee interaction, this could lead to a drop
in customer loyalty, which could lead to loss of customers (this could also be brought about
by the lack of personal service associated with internet shopping).

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10 a

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b i Explanation system:
• informs users of reasoning behind expert system conclusions and recommended
actions
• gives the percentage probability of accuracy of conclusions.
ii Inference engine:
• the main processing element of expert system
• acts as a search engine examining the knowledge base for information that matches
the queries
• the problem-solving part of expert system which uses inference rules from a
rules base
• the inference engine attempts to use the gathered information from the user to find
an object that matches.
iii Knowledge base:
• repository of facts
• stores all knowledge about an area of expertise obtained from a number of experts
• collection of objects and their attributes.
iv Rules base:
• set of interface rules
• … which are used by an inference engine to draw conclusions
• follows logical thinking, such as IF … THEN.
v User interface:
• expert system interacts with the user through dialogue boxes or command prompts
• usually has Yes/No answers and is based on responses from previous answers.
c • an interactive screen is presented to the user
• the system asks a series of questions about the fault found in the computer
• the user answers the questions asked
• a further series of questions are asked based on the user’s previous responses
• the inference engine compares faults entered with those in the knowledge base looking
for “known faults and their causes”
• once a match is found, the system suggests a remedy for the fault
• the system will give reasons for its recommendations including the probability that the
recommendations given will cure the fault
• the output will be in the form of text or a series of drawings showing internal
components and how to repair/replace them
• the user can request further information from the expert system.

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11 True False
Statement
() ()

NFC can work up to 50 metres away 

The RFID chip consists of a tag and an antenna 

GIS systems require complex command language interfaces 

Satellite signals are unaffected by bad weather and physical


obstructions, such as tree branches

Building a computer model is much cheaper than building the real thing 

One advantage of CAL is the ability of the student to stop at any point

and resume from where they left off at a later date

The first step in processing a cheque by taking an electronic image is


called 'out clearing'

Electronic funds transfer is a very insecure payment method 

3D printing uses five different coloured bio-ink cartridges (black, bio-


grade black, cyan, yellow and magenta)

Strategic games, such as chess, can be run on an expert system 

Cambridge IGCSE Information and Communication Technology Teacher's Guide 11

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

7 The systems life cycle

Answers to exercises
7a i alphanumeric/text
ii character
iii text
iv Boolean
v alphanumeric
vi numeric: integer
vii numeric: currency
viii numeric: real/decimal
ix numeric: date
x numeric: time
7b 1 a presence, length, format
b for example: aybs34ab
c for example:
153416135 would fail length and format check
<blank field> would fail presence check
[Note: use of alphanumeric is NOT a good validation check since any number-letter
combination would pass the validation check]

Cambridge IGCSE Information and Communication Technology Teacher's Guide 1

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2 Name: text
Date of birth: format check
Telephone number: alphanumeric check
Order ref number: length check
Sex: presence check
Primary key field: order ref number (should be unique)
7c

Cambridge IGCSE Information and Communication Technology Teacher's Guide 2

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7d 1 Data item Field Normal Abnormal Extreme

15 month 

12 month  

07 month 

1.6 month 

1 month  

0 month 

13 month 

March month 

1 day  

31 day   ()

18 day 

Tuesday day 

45 day 

0 day 

30 day   ()

0001 year  ()

2021 year 

90.55 year 

-25 year 

1854 year 

2 presence check
Using drop down boxes would avoid errors.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 3

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3 Name of resort: Bognor Regis (normal)

(presence check): A41322FF (abnormal)
Daily temp (average): 21 (normal)
(range check):
35 (normal)
5.6 (abnormal)
twenty-one (abnormal)
−15 (normal)
−18.6 (abnormal)
Hours of sunshine: 0 (extreme)
(range check):
24 (extreme)
12 (normal)
11.5 (abnormal)
−2 (abnormal)
twenty-one (abnormal)
32 (abnormal)
Answers to exam-style questions
Answers to questions 2 and 3 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a (d) Format check

b (c) Range check
c (b) Presence check
d (a) Length check
e (c) 30th May 2024
f (e) Validation can check that data entered is correct
g (c) 20 and 80
h (d) Abnormal
i (a) Serial changeover
j (d) Observing workers doing the tasks

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2 a Tick ()
Inputs to the current system
Data capture forms 
Report layouts 
Limitations of the system
Observation methods
Improvements to the system
User and information requirements
Validation routines 
Problems with the current system
File structures 

b this is data that has been used with current system/data not created for test purposes …
… therefore expected results are known
c Three from:
• program listing
• program language used
• program flowchart/algorithms
• system flowchart
• minimum memory requirements
• known 'bugs'
• file structures
• list of variables
• sample runs (and results)
• validation rules.
3 a Field name Data type
Breed_of_cow Text
Date_of_birth Date
Weight_of_cow Numeric: decimal/real
Average_milk_yield Numeric: decimal/real
Animal_passport_number Text

b Animal_passport_number
c format check
data in format: 3 digits/4 digits
length check
length of EXACTLY eight characters

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4 Technical User
Description of component documentation documentation
() ()

How to sort the data 

Hardware requirements 

How to load and run the software 

Program flowcharts/algorithms 

Troubleshooting guide/FAQs 

Validation rules/routines 

Purpose of the system  

Program listing/coding 

Glossary of terms 

Meaning of error messages  

5 Analysis
Design
Development and testing
Implementation
Documentation
Evaluation
6 a Direct implementation
b Pilot implementation
c Length check
d Design stage
e Modules (modular design)
7 a • compare the final solution with the original task
• identify any limitations of the system
• identify any necessary improvements that need to be made
• evaluate the user’s responses to using the new system
• compare test results from the new system with results from the old system
• compare performance of the new system with performance of the old system
• observe users performing set tasks (compare old with new)
• measure the time taken to complete tasks (compare old with new)
• interview users to gather responses about how well the new system works
• give out questionnaires to gather responses about the ease of use of the new system.

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b feedback from end-users, two from:

• newer, more modern equipment
• obsolescence
• changes in the company that require updating of the hardware.
c feedback from end-users, two from:
• changes in company structure/how the company works
• no longer supported
• changes in legislation that require software modifications.
8 a range check – numbers must be between 1 and 100 (inclusively)
type check – data needs to be numeric only
b Normal:
• data which is acceptable/valid …
• … with an expected/known outcome
• for example, month can be in range 1-12
Abnormal:
• data outside the limits of acceptability/validity
• should therefore be rejected/cause an error message
• for example, month: <1 or >12 or non-numeric value or non-integer values
Extreme:
• data at the limits of acceptability/validity
• for example, month can be 1 or 12 only
c Normal () Abnormal () Extreme ()
52 
1 
104 
100 
twenty-five 
99 

d This is data that has been used with current system/data not created for test purposes
… therefore expected results are known.
Live data is used to test a new system, to make sure that the results of the new system
match the results from the old system.

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9 a Three from:
• obsolescence of existing equipment
• changes to requirements or changes in law (for example, safety requirements or
environmental issues)
• old equipment cannot operate at the required levels
• there is no longer hardware and/or software support
• newer, more efficient and cleaner equipment
• the need to keep pace with competitors.
b Two from:
observation:
• possible to get better overall view of the current system
• results/data obtained are more reliable
• a relatively inexpensive method
• all inputs and outputs of the current system can be reviewed.
interviews:
• an analyst can probe more deeply how to get information needed
• can modify questions depending on previous responses
• body language and facial expression are key to truthful comments
• first-hand information from users.
questionnaires:
• very quick method of gaining data
• relatively inexpensive method
• individuals can be anonymous therefore there may be more truthful answers
• quick analysis is possible
• can be filled in at an interviewee's convenience.
existing paperwork:
• information could be obtained which may not be possible by the other methods
• an analyst can see for themselves how the paper system operates.
c Direct changeover:
• the company cannot go offline for more than eight hours
• therefore, none of the other phasing in methods will work
• the system needs to be changed overnight.

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10

Cambridge IGCSE Information and Communication Technology Teacher's Guide 9

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

8 Safety and security

Answers to exercises
8a Print out of the student's assessment, checked against criteria in the textbook.
8b Print out of the student’s article using section 8.2 of the textbook as the basis.
8c Print of the student’s findings/checked against criteria in the textbook.
8d i 25-Apr-2005 – weak – date (possibly a birthday)
ii Password1 – weak – easy to guess
iii ChapTer@06 – strong – mixture of characters
iv rX!3&tp% – strong – mixture of characters
v 111111" – weak – easy to guess

Answers to exam-style questions

Answers to questions 2 and 3 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 a Three from:
• electrocution
• fire hazard
• tripping hazard
• personal injury.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 1

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b Electrocution Fire hazard Tripping hazard Personal injury

• no drinks in the • do not overload • use cable ducts • use desks strong
room sockets to make wires enough to take
• check wires on • do not cover on the floor safe the weight of
a regular basis cooling vents on • cover exposed the equipment
and replace if equipment wires under • use desks large
worn • do not let dust desks etc. enough so that
• all equipment accumulate in • use wireless/ equipment is not
must be equipment Bluetooth too near the
regularly connectivity edge (and can
• good ventilation
checked wherever fall off)
• use low voltage
• use of an RCB possible
equipment
• have CO2/dry
powder fire
extinguishers

2 Three from:
• encrypt passwords
• change passwords on a regular basis
• only being asked for, or providing, a limited number of characters in a password
• two-factor authentication
3

Cambridge IGCSE Information and Communication Technology Teacher's Guide 2

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4 a • Giving out personal information to people you do not know could be used to carry out
identity theft.
• Sending out photos of yourself to people you do not know could lead to identity theft
or somebody impersonating you.
• Privacy settings may allow strangers to see photos of yourself on social media sites.
• Photos you post can link you to a place or an address (for example, if they show the
number plate on a car because it is possible to find your address from this information,
or if they show some form of school uniform this gives somebody information about
where they can find you).
• Always maintain privacy settings to stop 'non-friends' from contacting you and also
make sure you control who has access to your profile.
• Making friends with people you do not know is very risky as people may not be who
they say they are (many of the photos on social media sites are false).
• It is very dangerous to use your real name in public social networking sites, instant
messaging or chat rooms.
• It is very dangerous to enter private chat rooms with strangers.
• A user should never arrange to meet anyone for the first time on their own and should
always tell an adult first.
b Personal, two from:
• name
• address or email address
• ID card number/passport number
• IP address
• cookie ID
• advertising identifier on mobile phone
• date of birth
• banking details
• personal photographs.
Sensitive, two from:
• ethnicity/racial origin
• political views
• member of a political party
• member of a trade union
• religion/philosophical beliefs
• sexual orientation/gender
• non-serious criminal records
• medical history
• genetic data/DNA
• biometric data.

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5 Health Safety
Description of risk
() ()

Tripping over a loose wire on the floor 

Headaches caused by the glare from a computer screen 

Risk of electrocution caused from damaged insulation on


an electric cable

Broken leg injury caused by falling equipment 

Irritation of the eyes caused by ozone gas coming from


a laser printer

Repetitive strain injury caused by repeated use of a keyboard 

Neck strain from sitting in a prolonged position in front of a


computer monitor

Cambridge IGCSE Information and Communication Technology Teacher's Guide 4

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7 • e-safety
• sensitive data
• privacy settings
• hacking
• phishing
• link
• smishing
• encrypted
• secure sockets layer
• digital certificate
• authenticity.
8 a Software or hardware which sits between computer and external network and filters
incoming and outgoing network traffic. Any traffic not meeting certain criteria is blocked
and gives a warning to the user.
b Four from:
• to examine the 'traffic' between user’s computer (or internal network) and a public
network (for example, the internet)
• to check whether incoming or outgoing data meets a given set of criteria
• if the data fails the criteria, the firewall will block the 'traffic' and give the user (or
network manager) a warning that there may be a security issue
• the firewall can be used to log all incoming and outgoing 'traffic' to allow later
interrogation by the user (or network manager)
• criteria can be set so that the firewall prevents access to certain undesirable sites; the
firewall can keep a list of all undesirable IP addresses
• it is possible for firewalls to help prevent viruses or hackers entering the user’s
computer (or internal network)
• the user is warned if some software on their system is trying to access an external data
source (for example, automatic software upgrade); the user is given the option of
allowing it to go ahead or request that such access is denied.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 5

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9 a copying of credit/debit card …

• … using a skimmer …
• which copies all the data on the magnetic stripe
• this data is copied to magnetic stripe on a fake card
• if the card has a chip, a shimmer is used
• this copies chip and magnetic stripe data to produce a fake card
• it does not clone the chip, so the card can only be used for online purchases.
b fingerprint patterns are scanned …
• … and saved on a database
• the system compares patterns of ridges and valleys
• when scanned, the fingerprint is compared to one stored on a database.
c a pair of files on a user’s computer …
• … used to secure data sent over the internet
• files are divided into public key and private key
• these are shared between user and website to authenticate both parties
• made up of six parts (email of sender, digital certificate owner, serial number, expiry
date, public key, certificate authority digital signature).
d altering characters in data using an encrypted key …
• … so that data intercepted is unreadable without access to the same key
• when data undergoes encryption it is called cypher text; original data is called
plain text.
e voicemail phishing
• uses voicemail messages to trick a user into calling a phone number contained in
the message
• the user, on calling the number, will be tricked into supplying personal data thinking
the number is legitimate.
10 a Three from:
• fingerprint/thumbprint scans
• signature recognition
• retina scans
• iris recognition
• face recognition
• voice recognition.

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b Biometric
technique Advantages Disadvantages

• very high accuracy • for some people it is very intrusive,

• one of the most developed since it is still related to criminal
biometric techniques identification
Fingerprint • it can make mistakes if the skin is
• very easy to use
scans dirty or damaged (for example,
• relatively small storage
cuts to the finger)
requirements for the
biometric data created
• non-intrusive • if individuals do not sign their
• requires very little time to names in a consistent manner there
Signature verify (about five seconds) may be problems with signature
recognition verification
• relatively low-cost
technology • high error rate of 1 in 50
• very high accuracy • it is very intrusive
Retina • there is no known way to • it can be relatively slow to verify
scans replicate a person’s retina retina scan with stored scans
pattern • very expensive to install and set up
• very high accuracy • very intrusive
Iris • verification time is • uses a lot of memory for the data to
recognition generally less than be stored
5 seconds • very expensive to install and set up
• non-intrusive method • it is affected by changes in lighting,
Face the person’s hair, their age and if
• relatively inexpensive
recognition the person is wearing spectacles
technology
• non-intrusive method • a person’s voice can be easily
• verification takes less than recorded and used for unauthorised
5 seconds access
Voice • relatively inexpensive • low accuracy
recognition technology • an illness, such as a cold, can
change a person’s voice, making
absolute identification difficult or
impossible

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11 a the ability of a user to prove who they are – three common factors:
• something you know (for example, PIN)
• something you have (for example, mobile phone)
• something unique to you (for example, biometrics).
b a form of verification which requires two methods of authentication to verify who user is,
for example:
• an 8-digit PIN is sent to somebody’s smartphone (known as on-time password/code
or OTP)
• this is layered into, for example, a website which then authorises the user
• the number is valid for a limited time period.

12 a • protects email contents which may be sensitive in nature

• encrypted emails are useless without decrypting key
• three aspects of email to encrypt:
• the connection with the email provider (therefore if intercepted in transit,
encryption makes email unreadable)
• encrypt the actual message (in case the mailbox is hacked and then emails cannot
be understood)
• encrypt archived emails (stored emails should also be encrypted; if a hacker gains
access to the archive server, any emails are vulnerable unless encrypted)
b • key logging detects user activity on a computer
• key presses, such as PINs or credit card numbers, can be sent back to a cybercriminal
• cybercriminal can then use data to make purchases
• they are primarily designed to monitor and capture web browser activity to obtain
personal data
• they are a form of spyware
• they gather information by monitoring key strokes and storing them in a small file
which is automatically emailed to a cybercriminal.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 8

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

9 Audiences
Answers to exercises
9a Print out of the student’s presentations or on-screen slide show.
9b • sign a statement that you agree to privacy rules
• use a product key before software is actually downloaded
• software can record the MAC address therefore only allowing one device to
download software
• keep important files on a website which needs to be accessed when the software is run,
therefore only genuine software downloads would work since the product code could be
stored in the system and used as a passcode.

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

Answers to exam-style questions

Answers to question 6 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

2 • age range
• income levels
• interests
• impairments
• location of students (which might affect language used).

3 ()

Use of a product key 

Use of ethics in software

Click on a check box agreeing to licence agreement 

Use of holographic images 

Make the software cheaper to develop

Supply software on CD-ROM or DVD-ROM

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4 a software piracy – illegal copies of software (which are often distributed free of charge or
for a small fee)
b product key – a unique (for example, 4a3c0efab5aba8le) reference number which needs to
be keyed in before software can be installed on a user’s computer
• this checks whether the user downloading software has bought an original or they are
attempting to make multiple downloads
• the product key only works for a finite numbers of copies, which is part of the
purchase fee.
c copyright infringement – this is where copyright laws have been broken – for example,
illegal copying, illegal use of part of the software in another product, etc., using the name
of copyrighted software on another product and so on
5 a • If the user group is made up of older people, or even disabled people, who have visual
impairments, then it is important to make sure the kiosk has clear-to-read fonts
• Complex language can be a real turn off to people where, for example, English is their
second language; the text needs to be clear and easy to read for these reasons
• It is necessary to hold the attention of the users, otherwise they will give up using
the kiosk
• Good, attractive screen designs will attract users to the kiosk
• Keeping interfaces clear and easy to use attracts people; lots of typing can be very
frustrating, as can badly designed kiosk interfaces where the user seems to go 'round in
a big circle', unable to find what they want
b

c • interviewing a cross section of the target group to find out how to engage the audience
(if this involves a major ICT solution, then this may have to involve many of the
techniques that were described in Chapter 7)
• giving out questionnaires to people in the target group to find out their background,
interests, age range and so on, so that the final solution can be tailored to meet the full
range of the target audience
• carrying out market research – this could involve the two techniques described above,
but would certainly involve a more sophisticated and in-depth analysis of the data
received (it would depend on how large the target audience is likely to be).

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6 a • the audience could be young

• the audience may be teenagers
• the audience may be adults/older
• software must match the age of the audience
• more images, sounds, interactive for younger audience
• more words/facts for older/adult audience
• the experience of the audience may be variable
• more visual content is needed for younger people than for older people
• expectations of the audience may be different
• an audience of experts would expect more from a solution
• more explanation needed if audience members are not experts.

b • a unique product key needs to be entered when the product is first installed
• the system will check for duplicated numbers
• the system only runs with CD-ROM/memory stick attached
• parts of software are stored on a memory stick/CD-ROM
• a dongle needs to be attached.

Cambridge IGCSE Information and Communication Technology Teacher's Guide 5

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Cambridge IGCSE™ Information and Communication Technology

Student's Book answers

Exam-style questions and sample answers have been written by the authors. In examinations,
the way marks are awarded may be different. References to assessment and/or assessment
preparation are the publisher’s interpretation of the syllabus requirements and may not fully
reflect the approach of Cambridge Assessment International Education.
Cambridge Assessment International Education bears no responsibility for the example answers to
questions taken from its past question papers which are contained in this publication.

10 Communication
Answers to exercises
10a 1 John, Mary, Karl; Tim, Ahmed, Dimitri
2 John, Mary, Karl; Tim, Ahmed, Dimitri
3 Themselves plus John, Mary, Karl; Tim, Ahmed, Dimitri
4 Only the sender can see this.
10b A good, balanced argument from students. Each group should produce a poster showing the
reasons why it should be policed and reasons why it should not.

Answers to exam-style questions

Answers to questions 2, 3, and 4 in this section are example answers for past paper questions. The details of
the relevant past paper can be found with the corresponding exam-style question in the Student’s Book.

1 True False
Statement
() ()

The internet is part of the World Wide Web (WWW) 

All recipients of emails can see all the recipients in the Bcc and Cc lists 

Extranets allow intranets to be extended outside the normal organisation 

Forwarding of emails is always good practice to keep everyone in the


organisation or family informed

Using email groups increases the risk of identity theft 

Netiquette refers to the need to respect other users on the internet 

It is not always illegal to copy or forward email attachments 

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

2 a short for web log:

• a personal online diary/journal
• owner’s opinions/single author
• others can post comments
• frequently updated by owner
• postings tend to be in reverse chronological order
• a blog is a website.
b allows users to create/edit webpages using a browser
• many people can contribute/edit/update entries
• members of the group can contribute
• it holds information on many topics
• posting not in chronological order
• the structure is determined by users/contents
• Wiki is a website or software
• Wiki is usually objective.
3 • an intranet has restricted access/the internet is worldwide
• an intranet is used only within a company/organisation
• an intranet access has more control of data whereas internet access is public and has
no control
• an intranet is policed/moderated/managed
• an intranet has reduced unauthorised access to material whereas the internet has general
material
• an intranet can restrict access to some websites/the internet has no restrictions on websites
• data on an intranet is more likely to be reliable/relevant – anyone can add material on
the internet
• an intranet sits behind a firewall
• an intranet is protected by passwords/extra security layer – more chance of hacking on
the internet
• an intranet used to give information relating to company whereas the internet is general
information
• the internet has much more information.

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

4 Blog Microblog Wiki

() () ()

Very restricted in the size of the post 

Allows readers to edit posts 

Entries are not usually in chronological order 

Very difficult to customise 

5 Intranet Internet
() ()
Information on the network is specific to a particular company or

organisation

Requires a password and user ID to gain access to the network 

Allows public access to all information available 

The network is always behind a firewall giving some hacking and


virus protection
It is possible to access the network from anywhere in the world

using an ISP account

The network is owned by a private company or organisation 

The network gives access to unlimited amounts of data on many


topics

There is an unlimited amount of traffic on this network 

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 Cambridge IGCSE Information and Communication Technology Student's Book answers

7 a (b) ISP
b (a) Uniform resource locator
c (e) Secured
d (b) HTTP
e (e) name@website.info
f (d) Browsing
g (d) FTP
h (c) Allows a user to view webpages
i (c) Extranet
j (a) Spam

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