information technology for csec® examinations · pp32(b), 46(fig 2), getty/marek mnich p31(lc),...

Information Technologyfor CSEC® Examinations 2nd Edition

Howard Campbell

CSEC® is a registered trade mark of the Caribbean Examination Council (CXC). INFORMATION TECHNOLOGY for CSEC® EXAMINATIONS SECOND EDITION is an independent publication and has not been authorized, sponsored, or otherwise approved by CXC.

ISBN 978-0-230-48336-1 AER

Macmillan Education4 Crinan Street, London, N1 9XWA division of Macmillan Publishers Limited

Companies and representatives throughout the world.

www.macmillan-caribbean.com

ISBN: 978-0-230-42694-8 AER

Text © Howard Campbell 2014Design and illustration © Macmillan Publishers Limited 2014The author has asserted his rights to be identified as the author of this work in accordance with the Copyright, Design and Patents Act 1988.

First published 2010 This edition published 2014

All rights reserved; no part of this publication may be reproduced, stored in a retrieval system, transmitted in any form, or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publishers.

Typeset by E Clicks Enterprise, MalaysiaDesigned by Macmillan EducationIllustrated by TechTypeCover design by Clare WebberCover image by Corbis/JGI/Jamie Grill/Blend Images and Devon ShawPicture research by Catherine Dunn

The author and publishers would like to thank the following consultants and education professionals for their contribution to this edition:Consultants: Keith Burkette (St. Mary’s College, Trinidad and Tobago), Gareth Byrne (UK) and Alan Wood (UK)Teachers: Jamaica: Huntley Anderson, Shawnette Dewar, Kesha Fraser, Meleseia Hawthorne, Janice Jones, Haidie Morant, Aggrie Osbourne; St. Vincent: Sherricea Burgin, Soyini Clarke-Palmer, Sheddie Conliff, Veneisha Daniel, Suzanna Leigertwood Ollivierre, Michael ScottSpecial thanks to Channyatt Bullock-Ramsamooj, Ministry of Education, St. Vincent and the Grenadines, for facilitating a team review.

The author and publishers would like to thank the following for permission to reproduce their photographs:

Alamy/Art Directors & TRIP p41(b), Alamy/Pashkov Andrey p22(br), Alamy/Art Directors & TRIP p23, Alamy/Ted Foxx p39(a), Alamy/David Hancock p115(tcl), Alamy/Jiri Hera p8, Alamy/ D. Hurst p116(cl), Alamy/Brian Jackson p116(cr), Alamy/ Konstantin Iliev p49(l), Alamy/ Image Source p116(tl), Alamy/Indigo Photo Agency p31(brc), Alamy/Christopher King p27(i), Alamy/ Christopher King p17, Alamy/Marek Kosmal p31(blc), Alamy/ Ilene MacDonald p115(tl), Alamy/ Oleksiy Maksymenko p38, Alamy/Nenov Brothers Photography p50(bc), Alamy/Niels Poulsen p39(c), Alamy/NUAGE p50(a), Alamy/Guy Primo p115(bc), Alamy/Jeremy Sutton-Hibbert p115(tcr), Alamy/Aleksandr Ugorenkov p31(bll), Alamy/Finnbarr Webster p22(bl), Alamy/Westend61 GmbH p27(iv), Alamy/Shaun Wilkinson p49(r), Alamy/ ZUMA Press, Inc. p37(bl); Art Directors/Helene Rogers p129(bl); Howard Campbell p30(a); Corbis/Chris Collins p3(desktop), Corbis/ JLP/Jose L. Pelaez p232(c), Corbis/Ocean p46(fig1), Corbis/Edward Rozzo p37(cl), Corbis/ Gonçalo Silva/Demotix p41(c), Corbis/ Wavebreak Media LTD p35; Getty Images pp86, 232(b), Getty/AtomA p3(phone), Getty/Pawea Bartkowski p32(tl), Getty/Michael Bodmann p20, Getty/Keith Brofsky p116(c), Getty/Peter Dazeley pp34(blt), Getty/Felbert+Eickenberg/STOCK4B p115(br), Getty/Maciej Frolow p3(tablet), Getty/Halfdark p33(bl), Getty/Jetta Productions p33(tl), Getty/Howard Kingsnorth p3(laptop), Getty/Stephen Krow p27(ii), Getty/Ryan McVay p31(bl), Getty/Edgaras Marozas pp32(b), 46(fig 2), Getty/Marek Mnich p31(lc), Getty/Greg Nicholas p39(b), Getty/Neustockimages p130(tl), Getty/nullplus p34(blb), Getty/Oktaydegirmenci p33(b), Getty/George Pchemyan p27(iii), Getty/Chris Pritchard p95, Getty/Rouzes p39(t), Getty/Baris Simsek p48, Getty/Thinkstock Images p115(tr), Getty/Tsuji p31(br); Macmillan Education pp36(t), p115 (bl); NPG- a division of Macmillan Publishers Ltd p58(cr); Science Photo Library p51, Science Photo Library/CHASSENET p37(blt), Science Photo Library/DAVID PARKER p129, Science Photo Library/MARTIN RIEDL p232(a); Superstock/Corbis p36(bl), SuperStock/Cusp pp33(a), 46(fig3), 128(tl); Thinkstock p108; Theyummytruth.com – a great combination of eye-grabbing imagery and easy-to-navigate functionality p58(cl).

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iii

ContentsPage Finder v

About this book vi

Part 1: Theory1 The computer system 2

What is a computer? 3

Categories of computer systems 4

Components of a typical computer system 6

Interpreting computer specifications 8

2 Primary and secondary storage 13

How do primary and secondary storage differ? 14

How is storage capacity measured? 14

Types of primary storage devices 16

Secondary storage media 18

Comparing secondary storage media 23

3 Input and output devices 28

Data collection basics 29

Input, input devices and input media 29

Input devices in the home 31

Input devices in the retail trade 32

Output devices 37

4 The Internet and communications technology 47

Data communication and networks 48

The World Wide Web (WWW) 55

Communicating globally using network-based tools 57

5 Data storage and manipulation 62

Number systems 63

Binary addition 67

Binary subtraction 69

Representing integers 69

Storing text data 73

6 System programs and application programs 77

The difference between system programs and applications programs 78

System software 78

Functions of an operating system 79

Processing modes 83

Application programs 84

7 Information processing 91

Data, information and information processing 92

Data: Sources, verification and validation 95

File organisation and access 100

8 Data security 107

Introduction to data security 107

Common vulnerabilities and threats 109

Data misuse 111

Protecting your computer system 114

Operational procedures 118

9 The impact of ICT on jobs, skills and careers 124

The impact of Information Technology on jobs 124

Computer-related professions 125

Career opportunities for hardware support professionals 125

Career opportunities related to the Internet 127

Career opportunities in IT-related industries 127

Computer applications in business and industry 127

Computer-aided design 128

Computers in science and technology 129

Computers in education 130

Computer applications in recreation and entertainment 131

Telework – telecommuting and telemarketing 131

Part 2: Problem-solving and programming

10 Problem-solving and program design 135

Introduction to problem-solving 136

BVI Boat Hire 137

Problem partitioning (Creating an I-P-O chart) 137

Constants and variables 138

Data types 140

The concept of an algorithm 140

Ways of representing algorithms 141

Developing algorithms to solve simple problems 145

11 Program implementation 168

Generations of programming languages 169

Levels of programming languages 170

Implementing a program: The five steps 171

Writing programs in Pascal 173

Testing and debugging techniques 183

Arrays 185

iv

Part 3: Productivity tools

12 Mastering word processing 195

Introduction to word processing 196

Creating a document 199

Columns and tables 203

Working with graphics 206

Document editing 208

Formatting 216

13 Mastering presentations 231

Presentations 232

Creating a presentation 235

14 Mastering web page design 243

Introduction to web page design 244

Creating simple web pages 244

Creating and hosting your own website 248

15 Mastering spreadsheets 250

Introduction to spreadsheets 251

Features of spreadsheets 252

Creating and setting up your workbook 254

Data extraction 279

16 Mastering database management 292

Introduction to databases 293

Creating and populating a database 295

17 Information integration 336

Using data from Microsoft Access in Microsoft Excel 336

Using data from Microsoft Excel in Microsoft PowerPoint 338

Perform a mail merge using an external data source 338

The School-Based Assessment

18 Mastering the School-Based Assessment 345

Requirements of the School-Based Assessment 345

Mark allocation 346

Some tips to help you master the SBA 346

Practice your way to a high SBA score 346

Key skills and mark allocation 353

Answers to multiple-choice questions 356

Glossary 357

Index 363

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Syllabus sections

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Objective 1 3 137 170 48 92 196 251 293

Objective 2 6 138 169 53 93 208 252 293

Objective 3 16 139 171 53 95 216 267 293

Objective 4 15 140 184 107 97 221 270 295

Objective 5 23 140 173 109 99 201 261 295

Objective 6 18 141 174 127 100 210 262 298

Objective 7 29 145 175 128 100 203 266 319

Objective 8 37 157 180 126 216 267 302

Objective 9 63 159 185 125 215 259 313

Objective 10 8 183 338 262 313

Objective 11 78 172 213 274 321

Objective 12 80 201 279

Objective 13 83 232 276

Objective 14 84 233 282

Objective 15 80 235 282

Objective 16 236

Objective 17 236

Objective 18 236

Objective 19 239

Objective 20 237

Objective 21 237

Objective 22 239

Objective 23 239

Objective 24 244

Objective 25 244

Objective 26 246

Objective 27 247

Objective 28 247

Page finderThis page finder gives you the page number for all the objectives from each section in the new CSEC® Information Technology syllabus at your fingertips.

vi

About this bookThis book isn’t just words on a page.

This book contains a range of different features to introduce, teach and highlight key information throughout the course. These pages explain how to use them. The larger column contains the main text and diagrams; you can read straight down it without interruption.

The smaller column contains other useful facts, so make sure you use it to check your understanding. You should remember to spend time studying the fi gures and diagrams as well as the text.

✓ defi ne what a computer is

✓ describe a general-purpose computer system

✓ identify the major components that make up a typical computer system

✓ explain the function of the central processing unit

✓ explain the function of memory

✓ explain the function of storage

✓ explain the function of input and output devices

✓ interpret the hardware specifi cations of a computer system.

By the end ofthis chapteryou should be able to:

1

Instructions.indd 1 1/21/14 11:17 AM

4 • The Internet and communications technology

Answers to ITQs ITQ1 (a) A telecommunications technology providing wireless data, voice and video over long distances; (b) Digicel; (c) (i) facilitates more commercial activities as e-commerce facilities can be made available in places not served by wired telephone service or wired network; (ii) provides opportunities for the development of more innovative products/services.

ITQ2 (a) A hub is a passive device, switch is intelligent; (b) switch forwards data packets between computers on one network, router forwards data packets between computer networks.

ITQ3 (a) Fibre optic; (b) fibre optic; (c) twisted pair.

ITQ4 To download multimedia content such as music and movies.

ITQ5 Any THREE of: (a) to communicate using electronic data interchange (b) to publish catalogues for wholesalers and trade partners (c) to share training programmes (d) to provide team collaboration environments.

ITQ6 Any THREE of:.biz.com,.info.name,.net.org,.pro

IT portfolio1 This activity will explore the concepts related to data communications and networking.

a Check out the computer lab at school (make sure to get permission from your teacher before you do so); ask the following questions: i Are the computers networked? ii What types of cabling are used? iii Is there a server? iv Is the central connecting device a hub, switch or router? v Is there Internet access?

b Record your findings in your portfolio.

2 In this activity you will explore concepts related to Wi-Fi and the Internet. Conduct research (read books, use search engines on the Web and interview people) and record your findings in your portfolio:

a What is the name of the organisation that owns the Wi-Fi trademark?b When was the term ‘Wi-Fi’ first used commercially?c What wireless networking standard is used by Wi-Fi?d Describe the THREE most recent variations of the Wi-Fi standard. Ensure that you make mention of distance

limitations.e What does the logo look like? Have you ever seen the logo on a product or its packaging? Paste an image of the

logo in your portfolio.f Visit your local Internet café and find out if they offer VoIP telephone calls. What hardware and software

components are required?g Download Skype and make a VoIP telephone call. How does the cost and call quality compare with a call made

via a fixed line or mobile telephone?

59

IT portfolio1 In this activity you will explore printers.

a Interview at least five persons and find out the make and model of the printer they use. For example, if you interviewed me, I would tell you I use a Samsung ML-2165W).

b Conduct research to get more details about each of the printers based on the make and model supplied.c Copy the following table in your portfolio and complete it. Note that I have completed the first row based on

research done about my printer.

Make & Model Impact or Non-Impact Type Print Speed Print Resolution (dpi)Samsung ML-2165W Non-Impact Laser 21 PPM 1200

d Paste a picture of each of the printers.

2 In this activity you will explore input and output devices.

a Visit the web site of an online computer store (www.cdw.com, www.provantage.com or www.newegg.com).b Download at least TWO pictures of EACH of the following devices.

i barcode reader iv optical mouse ii electronic signature capture device v wireless keyboard iii optical mark reader (OMR)

c Print all the images and paste them into your portfolio, complete with a brief description (make, model, price and key features).

d Compare your pictures with at least two other people in your class. Note the similarities and differences.

Group activities1 This is a small-group activity for 3–4 people.

a Each group member should collect at least TWO source documents generated in each of the following scenarios:• a classroom environment• a home• a micro or small business (ask the Principles of Business teacher at your school what this is)• a meeting of a sports team or co-curricular activity (Cadet, Key Club, etc.)

b Compare the documents collected from each area. Note their similarities and differences.c Classify all the documents as either human-readable or machine- readable.d Suggest which device(s) are ideal for reading the documents categorised as machine-readable.e Paste the documents in your portfolio and record your findings next to each of them.

2 Your local police station has just received a donation of a digital camera and US$800 to purchase a printer suitable for printing crime-scene photos. The officer in charge of the station has sought your help to select a suitable printer. You have to co-opt two of your classmates to undertake this task. You are required to:

a Assess the needs of the police station and make a list of the TWO types of printers that the group believe are most suitable.

b For EACH type, identify TWO named printers available for sale at a local computer store or online retailer. Complete the table below.

Type 1 Type 2Printer 1 Printer 2 Printer 3 Printer 4

BrandModelResolutionPrint speedMemory capacityPrice

c Based on your findings, make a recommendation to the officer in charge.Place a copy of the recommendation in your portfolio.

3 • Input and output devices

44

A list of objectives at the beginning of each chapter tells you what topics you will be covering. They will help you to plan and measure your learning.

11

1 • The computer system

Examination-style questionsMultiple-choice questionsInstructions: Each of the following questions has four suggested responses labelled (A), (B), (C) or (D). Read each question carefully then select the most suitable response.

1 ____________ is an area of a computer that temporarily holds data that is waiting to be processed, stored, or output.

(A) Memory (B) Storage (C) Input (D) Output

2 The microprocessor’s ____________ unit fetches each instruction.

(A) instruction(B) integrated(C) circuit(D) control

3 Which of the following is likely to have the LEAST processing power?

(A) game consoles(B) mobile computers(C) mobile devices(D) servers

4 In what order do ICT systems deal with data?

(A) process, input, output (B) input, output, process (C) input, process, output (D) input, process, save.

5 The ____________ is dedicated to perform arithmetic operations, such as addition and subtraction.

(A) CPU (B) CU (C) ALU (D) ATA

6 What is a computer’s main internal backing store?

(A) CD-ROM (B) ROM (C) hard disk (D) processor

TEST BANK

7 The component that stores the program and data currently being executed is:

(A) arithmetic logic unit(B) floppy diskette(C) main memory(D) secondary storage

8 Which of the rows in the following table does NOT contain the correct information?

Computer specification

Hardware component

I 2.4 GHz Clock speed II 2 GB DDR Memory speed and type III 500 GB Hard drive capacity IV 5,400 RPM Hard drive speed

(A) I and II(B) II ONLY(C) II and III(D) IV ONLY

9 Specialised computer hardware can be used for home entertainment. Which one of the following is NOT specialised gaming hardware?

(A) Wii(C) Xbox(B) PlayStation(D) Super Mario Cart

10 Carefully consider the following statements about printed books and netbook-type computers. Which of these statements are UNTRUE?

I A computer and a netbook both store information.

II Books are portable, netbooks are not. III Computers are programmable, books are not. IV Computers only store small amounts of

information whereas books store a large amount of information.

(A) I and III ONLY(B) II and III ONLY(C) II and IV ONLY(D) I, II and IV ONLY

9780230426948_01_1_12.indd 11 8/7/14 4:33 PM

This is the style of question you may come across in your exam. Your teacher will suggest how you can use them, but they will measure what you have learnt and help to identify any gaps in your knowledge so you can revisit the relevant sections of the book.

The concept maps represent knowledge organisation visually to help you learn more meaningfully and enhance your knowledge integration. You can use them as tools to help connect prior knowledge with new information.

The expanded IT Portfolio now provides more opportunities for you to extend and reinforce the knowledge and skills introduced throughout the chapter. Most of the activities involve fi eld or web-based investigations.

A wide assortment of game-based and real-world problems is presented for small groups to complete. You and your classmates can improve on ideas as you share in fi nding solutions in an environment where the group evaluates its own success.

2

✓ defi ne what a computer is

✓ describe a general-purpose computer system

✓ identify the major components that make up a typical computer system

✓ explain the function of the central processing unit

✓ explain the function of memory

✓ explain the function of storage

✓ explain the function of input and output devices

✓ interpret the hardware specifi cations of a computer system.


1 The computer system

Concept mapConcept map

General-purposeComputer Systems

CPU:control unit

ALU

primary memory:ROMRAM

PROM

output devices:printersmonitorsspeakers

multimedia projectors

input devices:keyboardmouse

microphonescanner

bar code readers

general-purpose:desktopslaptops

notebooksnetbooks

smartphones

secondary storage:CD-ROM

DVDhard disk

flash drivesmemory cards

include major componentsperform major functions

processing input storage output

examples

such as

input/outputdevices

vii

Each image has a caption and a fi gure number to help with cross-referencing.

Suggested answers to the In-Text Questions will allow you to assess yourself.

The smaller column cancontain key facts. It isgood practice to spendtime reading this columnas well as the main text sothat you don’t miss anyimportant information.

The fi rst time an important new word appears in the text, it is highlighted at the side. Sometimes a short defi nition is given in the main text. An in-depth explanation is provided in the glossary at the back of the book.

There are a wide variety of activities to complete so that you can reinforce and extend your knowledge and skills that are covered in each chapter.

Summaries of the key facts from each module will help you check your understanding.

Where you see this icon, you will fi nd an In-Text Question (ITQ). These are spread throughout each chapter and will help you to check your progress. If you can’t answer the ITQ, you should refresh your knowledge by re-reading the relevant paragraphs in the main text. Answers to the ITQs are found at the end of each chapter.

ITQ1

118

8 • Data security

Operational proceduresBacking up dataIt is unwise to rely on a single storage device for storing important data. The device and the data it contains may fall prey to one of the accidental or deliberate actions or events mentioned earlier. To safeguard data, it is good practice to copy data to another storage device or media.

Adopting a regular backup system such as the Grandfather-Father-Son System means that if disaster should strike the organisation can recover almost all of its data quickly and business can continue as usual. It is important to keep each generation of backup separate from the rest. The son can be kept in the computer room, the father in a fireproof cabinet and the grandfather in another building. For a fast-moving business backups may be taken every day rather than every week. If a hard disk drive fails the most recent backup, the son, can be used to restore the data. In the event of a fire in the computer room destroying the son backup and the computer system, the father backup can be used to restore the company data. In the worst case, a whole building may be flooded but the grandfather backup can still be used to restore the data.

List THREE potential threats to a backup media?

ITQ15

A backup is a safety copy of files that can be used to recover data in case of an event that causes data damage or loss.

Figure 8.12 Passwords are a sequence of letters, numbers and special characters that must be supplied to access a resource. Passwords and usernames can be used so that only authorised users can log on to the system. In a secure system each individual user or group of users will be allocated privilege to access only the files and resources they need to perform their jobs.

Sign in to Online Banking

User ID:Password:

Sign In >

Figure 8.11 Windows Firewall is implemented as a software-only file security mechanism and is a component of the operating system.

Activity 8.4 Log on to FirstCaribbean International bank’s website at www.cibcfcib.com, then search for ‘Improving your own security’. Read some of the important steps that you can take to protect yourself online.

Figure 8.13 (a) The Backup or Restore tool is one of the Windows operating system accessories. (b) A user may choose what to back up and also what device to store the data on.

(a) (b)

119

8 • Data security

Grandfather, father and son.Grandfather: backup of the system from 2 weeks agoFather: last week’s backupSon: this week’s backup. Next week all the backups are older so the father becomes the grandfather, the son becomes the father, and a new son backup is created.

Archiving dataAn archive comprises the files created or received by an institution or organisation during the course of routine business that are stored because of their value.

Depending on the nature of the data, some companies may archive data monthly, others quarterly or annually. These files are usually stored on removable media such as DVDs or magnetic tapes and kept in a secure location. Files in an archive will be kept for a period of time and then destroyed.

archive ❯

Summary• Data security is all about identifying and assessing computer security risks.

• A computer security risk is any event, action or situation – intentional or not – that could lead to the loss of computer systems and the data they contain.

• Data integrity is concerned with ensuring the accuracy, completeness and internal consistency of the data stored in a database.

• Physical access restrictions can prevent unauthorised personnel from damaging the computer hardware.

• Access to IT systems can be restricted by requiring all legitimate users to input a valid username and password before being able to gain access to the system.

• A firewall acts as a barrier between a computer system and an external network.

• Encryption, overwrite protection, password, and making a file read-only access are mechanisms that may be used to help maintain file integrity.

• Individual files can be protected using encryption techniques that require the reader to have a correct password to decrypt the file.

• Viruses, Trojans and worms are malicious program that may infect and do harm to a computer system and its data; up-to-date antivirus software can protect computer systems from virus attacks.

• Computer fraud involves the use of computers to illegally obtain money, goods or services. There are many types of computer fraud including identity theft, credit card fraud, electronic eavesdropping and surveillance.

• Backups are copies of files that can be restored in the event that the original files are lost through hardware failure, accidental deletion or computer fraud whereas an archive comprises the files created, received and accumulated over time and retained for historical use.

Answers to ITQs ITQ1 The following are SOME possible situations: (a) hard disk failure caused by intermittent power outages causes partial data loss; (b) hard disk failure caused by a power surge causes total data loss; (c) laptop containing the data is stolen from a parked motor vehicle; (d) the file with the data is copied by an unauthorised person without the knowledge of the owner; (e) an employee copies data from the file for his/her personal use.

ITQ2 (a) The file containing the credit card details OR the file containing the student’s assignment. (b) The file with credit card details may have been accidentally selected and copied to the USB drive; the file with the assignment may have been intentionally copied to the USB flash drive by the accounting clerk. (c) Any reasonable explanation consistent with the answer in (b).

✓ identify common threats to the security of data

✓ identify common threats to the integrity of data

✓ outline ways by which information can be misused

✓ describe measures to secure data

✓ describe measures to maintain data integrity.


8 Data security

Concept map

may be protected usingsubject to

misuse:computer fraudcredit card fraud

electronic eavesdroppingidentity theft

industrial espionagepropaganda

software piracystorage of inaccurate information

surveillanceviolation of privacy

software restrictions:encryption

firewalloverwrite protection

passwordsread-only accessrestricted accessvirus protection

hardware access restrictions:

biometric systemsguardslocks

fire/waterproof cabinets

procedures:archiving

backup and recoverydisaster recovery mechanisms

laws

Data

Introduction to data securityWhy is there a need for data security?Existing manual systems are often computerised to improve the effi ciency of an organisation. As the system becomes operational, data is captured, processed, stored and disseminated. Organisations and their customers – other organisations and individuals – become dependent on computer systems and the information they provide. There are some drawbacks to computerisation. These include:

• data theft or loss

• loss of data integrity

• increased exposure of data and information to misuse

Data security is all about identifying and assessing computer security risks.data security ❯

108

8 • Data security

A computer security risk is any event, action or situation – intentional or not – that could lead to the loss of computer systems and the data they contain.

Data security allows individuals and organisations to assess the risks to which their computer systems and data is exposed, and determine and implement suitable countermeasures. It is important that an organisation protects its data adequately. Data that is damaged, lost, stolen or misused can cost the business money, its reputation or even the life of the business itself. The business may eventually have to close!

What are the main elements of data security?

computer security risk ❯

Element Meaning Example # 1 ABC Pharmacy

Example # 2Customer Jan Doyle

Vulnerability Exposure to the possibility of being attacked or harmed

Computer system is connected to a wide area network. It is also used to access their insurance company’s extranet.

Customer fills prescriptions at the pharmacy and makes payments using credit and debit cards.

Threat A statement of an intention to inflict damage

Data may be intercepted as it transmitted from the pharmacy to the insurance company.

Credit card data and personal data may be accessed by an unauthorised person.

Attack Actual action that causes damage Credit card data stolen over a period of weeks by an eavesdropper.

Unauthorised purchases made with credit card.

Countermeasure An action taken to prevent an attack or minimise its effect

Encrypt data before transmission. Use a credit or debit card with chip-and-pin technology.

What kind of data is at risk?Data in every format and at every stage of the processing cycle is vulnerable.

• Data being captured

• Data collected and awaiting processing

• Data being processed

• Data stored on removable media

• Data stored on networks

• Data in file libraries

• Data being transmitted over a communications network

• Data that has been backed up

• Data that has been archived

How are data security and integrity related?Data security and data integrity are two different concepts. Whereas data security is concerned with identifying and assessing risk, data integrity is concerned with ensuring the accuracy, completeness and internal consistency of the data stored in a database.

Data security plays a key role in maintaining data integrity as it provides the mechanism to safeguard files from corruption and unauthorised access.

Consider the following scenario.An accountant creates an electronic spreadsheet containing the credit card

details of 500 customers and saves this file on the desktop of his computer. He leaves his desk for a few hours to attend to company business. In his absence, an accounting clerk seizes the opportunity to use the computer to complete a school assignment. She creates a few files in the process and saves them on the desktop. When she is finished, she copies the assignment files, and

ITQ1Briefly describe THREE situations that may result in the damage, loss, theft or misuse of data that is stored on the hard disk of a computer system.

ITQ1

data integrity ❯

Table 8.1 Main elements of data security.

Figure 8.1 A credit card with a microchip may help to prevent credit card fraud.

information technology for csec® examinations · pp32(b), 46(fig 2), getty/marek mnich p31(lc),...

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