BS 240 INTRODUCTION TO DATA PROCESSING … · BS 240 - INTRODUCTION TO DATA PROCESSING/MANGEMENT OF...

PREPARED BY O. NDHLOVU – 2009 BS240

BS 240 - INTRODUCTION TO DATA PROCESSING/MANGEMENT OF INFORMATION TECHNOLOGY

Objectives To give a thorough and up-to-date grounding in the realities of commercial

applications of Information and Communication Technologies (ICT’s).

To Examine the roles of data, information and knowledge within modern business

organisations, and the roles that information and communication technologies (ICT’s) play in supporting people and groups within organisations.

To provide students with a thorough understanding of how the various information

and communication technologies work, the basic principles on which they are built

and their role in computer based systems in the business community.

To give an insight into the historic development of computer technology and its

impact on business management.

Syllabus 1. DATA AND INFORMATION

Introductory concepts of Data and Information (definition, representation, storage).

General characteristics or attributes that add value to information. Value of information in the modern business enterprise.

Role of data and information in business. Information uses and flows in management.

The Information and Communication Technology (ICT) Paradigm. Integration of ICT’s into modern business practices.

The Data processing cycle.

2. COMPUTERS AND ASSOCIATED PERIPHERALS

Introduction to key ICT technologies. Brief history of the computer.

Computer systems: Types and general categories (micro-computer, supercomputer, minicomputer, mainframe). Other categories and mobile business productivity.

(PDA’s, Palmtops, Handhelds, Smart phones etc..)

Architecture and structure of computer systems. Computer data representation. Data,

fields, records, files and databases. Data and Information handling Importance (Entry,

validation, verification)

Input Devices: General Categories, VDU (touch and non touch sensitive), keyboard, Mouse, Optical Character Recognition (OCR), Image Recognition Systems, Magnetic

Ink Character Recognition (MICR), card and badge readers, Radio Frequency

Identification (RFID), Point-Of Sale (POS) system, voice and sound data input,

motion sensor input, Optical/Image Scanners etc. Computer Data Storage Devices: Magnetic tape, Magnetic disks, Optical Disks, USB

Drives, Memory cards, Hard Drives, Floppy Disks etc..

Output Devices: Printers types and usage (Dot Matrix, daisy wheel, laser printer,

Thermal printers, ink-jet printers, graph plotter, computer output on microfilm

(COM), fax, VDU, voice data output.

Computer Memory: RAM, Processor Registers, Cache Memory, Virtual Processing and the execution cycle. Batch, On-line, Real-time processing.


3. COMMUNICATIONS SYSTEMS

The Communications Model: General Layout, Need for communication, the business

enterprise and communication. Distributed and centralised processing. Data Transmission: Data transmission systems, Data Switching; Simplex, Duplex and

Half Duplex transmission; data transmission equipment (Modems, Acoustre couplers,

multiplexers).

Computer Networks: Role of networks, distributed and centralised networks (and examples), Network topologies, their characteristics and advantages (Ring, Star,

Hierarchical, multi-drop, etc). Computer Network Types: wired and non-wired.

Network protocols PANs, LANs (Intranet, Ethernet, Extranet), WANs, LHNs, the Internet.

4. SOFTWARE

Definition of software. Need for software. Software types: Systems Software (Operating systems, Communications software) Utility Software (Database

Management Systems) Application Software (General purpose, Specialised

Software).

Shareware, Open Source Software (OSS), Freeware.

Webware, Groupware. Productivity and Software.

Operating Systems (OS): OS enabled functions. OS Features. Choosing an OS

(advantages, specifications, purpose). Applications Software: Spreadsheet applications, Word Processors and other

productivity applications).

Acquisition of software (Off the Shelf, Tailored software, in-house developed, outsourced development).

Licensing, Purchase and Use of Software, End User Licensing Agreement (EULA).

Copyright, Trade Marks, Intellectual Property.

5. COMPUTER APPRECIATION

Practical Orientation to applications software: Basic Computer Operation and File

management, Word Processors, spreadsheets, Presentation tools, Accounting

packages, Database Management Systems, Internet Browsers.

6. THE ORGANISATIONS AND INFORMATION TECHNOLOGY

The digital firm: Organisation structure and IT departments. Roles of an IT department in the organisation.

IT department organisation structure: Staff Specialisations, Staff roles and

responsibilities in an IT department.

Control & Security in IT Departments (physical access, programmed access, backup).

Safeguarding organisational data.

7. INTRODUCTION TO SYSTEMS CONCEPTS AND SYSTEMS ANALYSIS

Definition of Systems. Introduction to Information Systems. IT and IS.

Systems Analysis, Systems Design, Implementation of Design.

8. INTRODUCTION TO E-COMMERCE

Business conversion to electronic device usage (advances ICT). Channels of

eCommerce. Types of eCommerce.

The Internet and eCommerce. Business process transformation effects of eNetworks.

The emergence of new business models and evolution of traditional ones.

9. PROFESSIONAL ISSUES Acquisition of Software, hardware considerations and ICT performance. Ethics and

the use of ICT’s. Piracy, Fraud and Computer Misuse.


Reading list: Information Technology: Inside and Outside by David Cyganski, John A. Orr, and Richard F. Vaz. Schaum's Outline of Introduction to Computer Science by Pauline Cushman and Ramon Mata-Toledo

Computer Science Made Simple: Learn how hardware and software work-- and how to make them work for you! (Made Simple) by V. Anton Spraul. Business Information: Technology, Systems and Management by Paul Bocij, Dave Chaffey, Andrew Greasley, and Simon Hickie. Computer Science: An Overview by J. Glenn Brookshear. Computer Science by Carl French.

Using Information Technology by Brian K. Williams and Stacey Sawyer. Management Information Systems by Kenneth C Laudon and Jane P Laudon. Business Information Systems by Dave Chaffey.

Assessment

Examination : 60% Course work : 40%

Assignment Due Date

Submit Assignments 1, 2 and 3 Before 4th October 2008.

Hand written assignments will not be accepted.


Detailed Contents

Contents

Objectives .............................................................................................................................. 1

Syllabus ................................................................................................................................. 1

Reading list: ........................................................................................................................... 3

Assessment ............................................................................................................................. 3

Assignment Due Date ............................................................................................................. 3

Detailed Contents ................................................................................................................... 4

UNIT 1: Information ............................................................................................................ 11

1.1 Data and Information .................................................................................................. 11

1.1.1. DATA PROCESSING (DP) ................................................................................ 11

1.1.2. GENERAL CHARACTERISTICS OF INFORMATION .................................... 12

1.1.3. VALUE OF INFORMATION ............................................................................. 12

1.1.4. ROLE OF INFORMATION IN BUSINESS ........................................................ 13

UNIT 2: Management ........................................................................................................... 13

2.1 Introduction ................................................................................................................ 13

2.2 Levels Of Management ............................................................................................... 13

2.2.1. TOP OR STRATEGIC LEVEL ........................................................................... 13

2.2.2. MIDDLE/TACTICAL MANAGEMENT ............................................................ 14

2.2.3. OPERATIONAL MANAGEMENT .................................................................... 14

2.2.4. INTERRELATIONSHIP OF LEVELS ................................................................ 15

2.3 Functions Of Management .......................................................................................... 15

UNIT 3: Hardware................................................................................................................ 16

3.1 The Computer ............................................................................................................. 16

3.1.1. ANALOGUE COMPUTERS .............................................................................. 16

3.1.2. DIGITAL COMPUTERS .................................................................................... 16

3.2 History Of Computers ................................................................................................. 16

3.3 Types Of Computers ................................................................................................... 17

3.4 General categories of computer systems ...................................................................... 17

3.5 Productivity and Business on the Go ........................................................................... 18

3.6 Architecture Of Computer Systems ............................................................................. 18

3.6.1. COMPUTER REPRESENTATION OF DATA ................................................... 19

3.6.3. THE CPU AND PRIMARY STORAGE ............................................................. 20


3.6.4. MICROPROCESSORS AND PROCESSING POWER ....................................... 21

3.6.5. MULTIPLE &PARALLEL PROCESSING ......................................................... 22

UNIT 4: Input Devices ......................................................................................................... 22

4.1 Human Computer Interaction ...................................................................................... 22

4.2 Data Capture and Entry ............................................................................................... 24

4.2.1. POINT-OF SALE (POS) SYSTEM ..................................................................... 24

4.2.2. BAR-CODED AND MAGNETIC STRIPS ......................................................... 24

4.2.3. TAGS ................................................................................................................. 25

4.2.4. DIRECT INPUT DEVICES ................................................................................ 25

4.2.5. ON-LINE SYSTEMS .......................................................................................... 25

4.2.6. KEYBOARD ENTRY......................................................................................... 25

4.2.7. KEY-TO-DISK/ TAPE SYSTEM ....................................................................... 25

UNIT 5: Storage Devices ...................................................................................................... 25

5.1.1. MAGNETIC DISK ............................................................................................. 25

5.1.2. MAGNETIC TAPE ............................................................................................. 26

5.1.3. FLASH DRIVES AND MEMORY CARDS........................................................ 26

5.1.4. OPTICAL DISK ................................................................................................. 26

5.2 New Storage Alternatives:........................................................................................... 26

5.2.1. SAN: ................................................................................................................... 26

5.2.2. SSP: .................................................................................................................... 26

5.3 Output Devices ........................................................................................................... 26

5.3.1. PRINTERS ......................................................................................................... 27

5.3.2. MICROFORM RECORDERS ............................................................................. 27

5.3.3. GRAPH PLOTTERS ........................................................................................... 27

EXERCISE 1 .................................................................................................................... 27

UNIT 6: Communications..................................................................................................... 28

6.1 Data Transmission ...................................................................................................... 29

6.1.1. DATA TRANSMISSION SYSTEMS ................................................................. 29

6.1.2. SIMPLEX, DUPLEX AND HALF DUPLEX TRANSMISSION ......................... 29

6.1.3. INTERFACE DEVICES ..................................................................................... 29

6.2 Network architectures: layers, protocols ...................................................................... 29

6.2.1. COMPUTER NETWORK STANDARDS ........................................................... 29

6.2.2. TCP/IP PROTOCOL ARCHITECTURE ............................................................. 30

UNIT 7: Network topology ................................................................................................... 32


7.1 Introduction ................................................................................................................ 32

7.1.1. CENTRALISATION........................................................................................... 33

7.1.2. DECENTRALISATION ..................................................................................... 33

7.1.3. HYBRIDS ........................................................................................................... 33

7.2 A Detailed look at specific network topologies ............................................................ 34

7.2.1. BUS NETWORK ................................................................................................ 34

7.2.2. RING NETWORK .............................................................................................. 34

7.2.3. STAR NETWORK .............................................................................................. 35

7.3 What is Ethernet? ........................................................................................................ 36

UNIT 8: Network Types & Span .......................................................................................... 36

8.1 Other Network Terminologies ..................................................................................... 37

8.2 Data Communications Rates and Capability ................................................................ 37

EXERCISE 2 .................................................................................................................... 40

UNIT 9: Software ................................................................................................................. 40

9.1 Introduction ................................................................................................................ 40

9.2 Evolution of Computer Software ................................................................................. 41

9.2.1. FIRST AND SECOND GENERATION LANGUAGES (1GL&2GL) ................. 41

9.2.2. THIRD AND FOURTH GENERATION LANGUAGE (3GL&4GL) .................. 41

9.3 General types of Software ........................................................................................... 41

9.3.1. SYSTEMS SOFTWARE ..................................................................................... 41

9.3.2. UTILITY SOFTWARE ....................................................................................... 41

9.3.3. APPLICATION SOFTWARE ............................................................................. 42

9.4 More on Systems Software .......................................................................................... 42

9.4.1. OPERATING SYSTEMS .................................................................................... 42

9.4.2. UTILITY SOFTWARE ....................................................................................... 43

9.4.3. COMMUNICATION SOFTWARE..................................................................... 43

9.4.4. DATABASE MANAGEMENT SYSTEMS (DBMS) .......................................... 43

9.5 Operating System Enabled Functions .......................................................................... 44

9.5.1. MULTIPROGRAMMING .................................................................................. 44

9.5.2. TIME SHARING ................................................................................................ 44

9.5.3. MULTIPROCESSING ........................................................................................ 44

9.5.4. VIRTUAL STORAGE ........................................................................................ 44

UNIT 10: Acquisition of Software ........................................................................................ 44

10.1 In-House Developed Software ................................................................................... 45


10.2 Off-The-Shelf Software:............................................................................................ 45

10.3 Out-Sourced Software Development ......................................................................... 45

10.4 FOSS (Free and Open Source Software) .................................................................... 46

10.4.1. FREEWARE: .................................................................................................... 46

10.4.2. OPEN SOURCE SOFTWARE: ......................................................................... 46

10.4.3. WEBWARE: ..................................................................................................... 46

10.4.4. SHAREWARE: ................................................................................................. 46

10.4.5. GROUPWARE: ................................................................................................ 46

10.5 Acquisition Method Factors ...................................................................................... 46

EXERCISE 3 .................................................................................................................... 47

UNIT 11: Licensing, Purchase and Use of Software ...................................................... 48

11.1 Introduction ............................................................................................................ 48

11.2 Intellectual Property............................................................................................... 48

11.3 Copyright ................................................................................................................ 48

11.4 Trade Marks ........................................................................................................... 48

11.5 Licensing ................................................................................................................ 48

11.6 Acquisition and Use of Software .......................................................................... 48

11.7 End User Licensing Agreement (EULA) .............................................................. 49

UNIT 12: Computer Appreciation ..................................................................................... 49

12.1 Computer Applications .......................................................................................... 49

12.2 Basic file handling and Management ................................................................... 51

12.2.1. KEY TERMS AND CONCEPTS ................................................................... 51

12.2.2. THE IMPORTANCE OF FILE ORGANISATION ........................................ 52

12.3 Creating folders ..................................................................................................... 52

UNIT 13: Word Processor Application ............................................................................. 53

13.1 Introduction to Microsoft Word ............................................................................. 53

UNIT 14: Spreadsheet Application ................................................................................... 57

14.1 Introduction to Office Excel ................................................................................... 57

14.2 Exercise 1: Working with Workbooks and Worksheets. ..................................... 58

14.3 Exercise 2: Editing Existing Data ......................................................................... 58

14.4 Exercise 3: Formula Creation ............................................................................... 59

14.5 Exercise 4: Using Predefined Formulae .............................................................. 59

UNIT 15: Database Systems ............................................................................................ 60

15.1 Introduction ............................................................................................................ 60


15.2 Purpose of Database Systems ............................................................................. 61

15.3 Types of Databases .............................................................................................. 62

15.4 Database Management Systems Composition ................................................... 63

15.4.1. DATA DEFINITION LANGUAGE (DDL) ...................................................... 63

15.4.2. DATA MANIPULATION LANGUAGE (DML) .............................................. 63

15.4.3. DATA DICTIONARY ..................................................................................... 63

15.5 Database Administration ....................................................................................... 63

UNIT 16: The Organisation and Information Technology............................................... 64

16.1 Introduction ............................................................................................................ 64

16.2 The Digital Firm ..................................................................................................... 64

16.2.1. WHY USE COMPUTERS ............................................................................. 64

16.2.2. COMMON DATA APPLICATIONS: ............................................................. 65

16.3 The Digital Firm & Computing Applications......................................................... 65

16.4 Integrated Appliances & New Business Models ................................................. 66

UNIT 17: Organisation structure and IT departments..................................................... 66

17.1 Roles of IT Departments in the organisation ....................................................... 66

17.2 IT department Staff Specialisations ..................................................................... 66

UNIT 18: Control & Security in IT Departments .............................................................. 67

18.1 Introduction ............................................................................................................ 67

18.2 The Organisation & Control .................................................................................. 68

18.3 Other types of control ............................................................................................ 69

18.4 Application Controls .............................................................................................. 71

18.5 Security Risks and Threats to Information Systems........................................... 71

UNIT 19: Classification of Files ........................................................................................ 71

19.1 Introduction ............................................................................................................ 71

19.2 File Classifications ................................................................................................. 72

19.3 Master Files and Transaction files ....................................................................... 72

19.4 File Organisation ................................................................................................... 72

UNIT 20: Introduction to Systems Concepts ................................................................... 73

20.1 Definition of Systems. ........................................................................................... 73

20.2 Types Information Systems .................................................................................. 74

20.3 Components of an information system ................................................................ 74

UNIT 21: Systems Analysis & Design .............................................................................. 75

21.1 Introduction to systems Development ................................................................. 75


21.2 Systems Development Life Cycle (SDLC) .......................................................... 76

21.3 Systems Analysis .................................................................................................. 76

21.3.1. INITIAL INVESTIGATION ............................................................................. 76

21.3.2. SYSTEMS SURVEY ..................................................................................... 76

21.3.3. FEASIBILITY STUDY.................................................................................... 77

21.3.4. INFORMATION NEEDS IDENTIFICATION AND SYSTEM

REQUIREMENTS ...................................................................................................... 77

21.4 Systems Design ..................................................................................................... 77

21.5 Implementation of Design. .................................................................................... 77

UNIT 22: Introduction to E‐Commerce............................................................................. 78

22.1 Introduction ............................................................................................................ 78

22.2 E‐Business ............................................................................................................. 78

22.3 E‐Commerce .......................................................................................................... 79

22.4 Types of E‐Commerce .......................................................................................... 79

22.5 Growth of E‐Commerce ........................................................................................ 79

UNIT 23: Benefits and limitations of E‐Commerce ......................................................... 80

23.1 Benefits to Organisations ...................................................................................... 80

23.2 Benefits to consumers........................................................................................... 81

23.3 Benefits to society ................................................................................................. 81

23.4 Limitations of E‐commerce ................................................................................... 82

23.5 Future of E‐commerce .......................................................................................... 83

EXERCISE 4 .................................................................................................................. 83

ASSIGNMENTS ...................................................................................................................... 84

ASSIGNMENT 1 ................................................................................................................. 84

ASSIGNMENT 2 ................................................................................................................. 85

ASSIGNMENT 3 ...................................................................... Error! Bookmark not defined.







List of Tables TABLE 1: Examples Of ASCII & EBCDIC Codes ............................................................... 20

TABLE 2: Data Capacity Standard Units .............................................................................. 20

TABLE 3: Examples of Microprocessors .............................................................................. 21

TABLE 4: Device and Descriptions ...................................................................................... 22

TABLE 5: Network Type & Transmission Rate .................................................................... 39

TABLE 6: Common Software Applications ...................................................................... 49

TABLE 7.Specific Types of Control .................................................................................. 69

List of Figures FIG. 1: Data and information. ............................................................................................... 11

FIG. 2 Decision Type and Detail........................................................................................... 14

FIG. 3 Management Function and information usage ............................................................ 14

FIG. 4 A Summary of the Computer Generations .................................................................. 17

FIG. 5 Computer Systems Illustrative Diagram ..................................................................... 19

FIG. 6 The communications model ....................................................................................... 29

FIG. 7 The OSI Reference Model ......................................................................................... 30

FIG. 8 Layers in the TCP/IP protocol architecture ................................................................. 31

FIG. 9 Data encapsulation..................................................................................................... 32

FIG. 10 Network topologies ................................................................................................. 32

FIG. 11 Bus network ............................................................................................................ 34

FIG. 12 Ring Network .......................................................................................................... 34

FIG. 13 Star Network ........................................................................................................... 35

FIG. 14 Network Card .......................................................................................................... 36

FIG. 15 Modern Network Illustration .................................................................................... 37

FIG. 16 Device Management ................................................................................................ 43

FIG. 17 A typical desktop setup........................................................................................ 52

FIG. 18 Visual Illustration of the GUI in Microsoft Office 2007 ...................................... 53

FIG. 19. Exercise 1: Editing Text ...................................................................................... 53

FIG. 20. Sample layout of text .......................................................................................... 54

FIG. 21. Exercise 2: Applying Styles ................................................................................ 54

FIG. 22. Layout for Exercise 2 .......................................................................................... 55

FIG. 23 . Exercise 3 Editing Styles ................................................................................... 56

FIG. 24. Exercise 4: Auto Section Numbering ................................................................ 56

FIG. 25. Layout for Auto Numbering ................................................................................ 56

FIG. 26. Exercise 5: Table of Contents Generation ........................................................ 57

FIG. 27. Illustration of a database .................................................................................... 62


UNIT 1: Information Data and Information. Role in business, general characteristics, value of

information, information flow in the business, levels and categories of

management.

1.1 Data and Information

Data contrast, are streams of raw facts representing events occurring in organizations or the physical environment. These are facts describing an entity or event by providing

the basic description of the characteristics of the entity or event. Information on the

other hand is the resultant of creation of meaning and context to data. That is data that has been shaped into a form that is meaningful and promoting understanding in a given

context. A brief example contrasting information to data may prove useful.

Supermarket checkout counters generate millions of pieces of data, such as product

identification numbers or the cost of each item sold. Such pieces of data can be totalled and analyzed to provide meaningful information such as the total number of bottles of

dish detergent sold at a particular store, which brands of dish detergent were selling the

most rapidly at that store or sales territory, or the total amount spent on that brand of dish detergent at that store or sales region (see below)

FIG. 1: Data and information.

1.1.1. DATA PROCESSING (DP)

Data Processing is the process of producing meaningful information by collecting all

items of data together and performing operations on them to extract the required information from them. See illustration below: -

The methods of Data Processing vary from those that are almost entirely manual to

that rely largely on the use of electronic computers. Current large scale data processing methods incorporate computers and are generally referred to as

computerised commercial data processing. In the modern world the potential of


computers is fully understood and thus most of today’s data processing is undertaken

primarily with the aid of computers.

1.1.2. GENERAL CHARACTERISTICS OF INFORMATION

For information to be useful, it must possess several characteristic attributes. These

attributes invariably add value to a piece of information or a potential increase in

desired attributes also increases the value or perceived value of that piece of

information. The following are a few attributes that when associated with information adds value or worth to that information:-

i) Reliability: must accurately represent the events or activities of an

organization, ii) Relevant: make a difference to the decision maker by reducing uncertainty

or by adding increased knowledge or value to the decision maker.

iii) Timely: provided in good time to affect decision-making process. iv) Complete: includes all relevant data or aspects of the data that are required.

v) Concise: Must be able to depict the required scenario without presenting un-

required information.

vi) Understandable: when information is presented in a form that is useful and

intelligible to the user.

vii) Presentable: Similar to understandable but includes an element of projecting

the precise representation in an orderly fashion.

INFORMATION = DATA + PROCESSING

viii) Verifiable: Independently generated information of the same process must

be the same or within reasonable variance. This could also be a function of

the source reliability. ix) Error free: data sets must contain a minimum number of errors. Also

referred to as precise when a single data element is considered.

There are several other attributes not mentioned above that can be added to this list.

However care is to be taken before inclusion to reflect beneficial attributes to a

manager or decision maker in the context of the course and the use of information

for business purposes.

1.1.3. VALUE OF INFORMATION

The value of information can be assessed in a number of ways: -

i) ATTRIBUTE CONSIDERATION: The number of desirable attributes a

piece of information has. ii) SUBJECTIVELY: This implies that perception is used to assess the value

of information. For instance current affairs maybe less valuable information

to an astronomer than to a political scientist. iii) QUANTITATIVELY: Using the cost benefit analysis. The value of

information is the difference between the benefit produced by the

information This can be expressed by the following formula:

Value = Benefits of the Information – Cost of Acquiring that Information

The value of information can also be derived quantitatively by assessing the benefits

of having the information in a decision making scenario versus making the decision in the same scenario without the information. An illustration is presented as follows:

Value = Dwith- Dwithout

[Where: Dwith = Decision Making Scenario Benefits with the information available

Dwithout =Decision Making Scenario without the information available]


1.1.4. ROLE OF INFORMATION IN BUSINESS

i) The decision-making process: one important role of information is to support decision making by decision makers in an organization.

ii) The other role of information is to generate knowledge for organizations.

We define knowledge as information plus know-how.

UNIT 2: Management

2.1 Introduction

What is management? Management is a social process entailing responsibility for the

effective and economical planning and regulation of the operations of the organization

in the fulfilment of a given purpose or task involving, judgement and decision making in determining plans and in using data to control performance and progress against

plans and, Management is also the guidance, integration, motivation and supervision of

personnel comprising the enterprise and carrying out its operations. To manage, in summary is:

o To plan for something to take place;

o To make and issue decisions to execute the plan;

o To direct and coordinate activities to ensure that the plan is fulfilled; o To monitor the results of the executed plan so as to control events by making

them conform to the plan or, if necessary, by modifying the plan.

2.2 Levels Of Management

In the typical and fairly large organisation, management is organised in the traditional

hierarchical manner. Implying the existence of several levels of management with increasing or decreasing orders of seniority and responsibility. The following are the

levels of management in a typically large organisation using the traditional hierarchical

management structure: 1) Strategic Management e.g. Chief Executive, Board of Directors

2) Tactical Management e.g. all types of middle management, departmental

managers, functional managers such as the personnel manager, accountant, salesmanager.

3) Operational Management e.g. foreman, supervisor, chief clerk

A major factor in deciding the categories of management is the planning horizon. This

ranges

from long term at the highest level to short term, almost day-to-day, at the lowest level.

Another factor is the scope of influence. This is the jurisdiction to which the influence a

manager can exert lies. Other distinguishing factors include complexity of decisions

made, type of information handled and methods used to arrive at decisions.

2.2.1. TOP OR STRATEGIC LEVEL

Responsible for the overall setting of objectives and formulation of policy. Typical tasks include; corporate and term range planning, investment appraisal, middle

management

appointments, unstructured decision making. They are also responsible for monitoring


performance of middle management and are accountable to council members,

shareholders etc.

2.2.2. MIDDLE/TACTICAL MANAGEMENT

Responsible for the implementation of top management policy, which is often

expressed in the corporate plan. Responsible for setting sub objectives and for

functional planning, heavily involved with monitoring and control procedures.

Usually have clearly defined functional roles. Responsible to top management and responsible for operational management.

2.2.3. OPERATIONAL MANAGEMENT

Responsible for the day to day processes of supervision and direction of the routine, but

essential activities of the organisation e.g. rating, invoicing, despatch etc. Roles are

clearly defined and usually closely monitored. Decision making is involved but of a

structured,

programmed nature. Exceptional items would be referred to their superior at middle

management level. FIG. 2 Decision Type and Detail

FIG. 3 Management Function and information usage


Figures 1 and 2 depict the increasing and decreasing levels of information type and

usage

across the management levels. They also provide a summary on how information is

used, in

what form and for what purpose. The diagrams also depict The levels of

responsibility and

other functions performed by management to an appropriate degree.

2.2.4. INTERRELATIONSHIP OF LEVELS

The activities of the three levels are interrelated and must not be thought of as self-

contained and separate bands. Information flows in both directions, discussions, instructions, advice, results and so on continually flow between the levels in order to

achieve co-ordinated activities and better decision making. As an example, consider

the activities and interrelationships which are necessary in just one area - materials and inventory control: at the operational level Materials/inventory control is

dependent on; physical movement and storage, clear parts/material identification,

prompt and accurate recording of transactions, clear guidelines on stock levels, order quantities and so on. At the tactical level materials/inventory control is dependent

on; accurate summarisation of all operational matters affecting materials and

inventory, the setting of key decision values (stock levels, reorder quantities etc.), setting of materials budgets within policy guidelines, ordering, price negotiations

and so on. At the strategic level materials/inventory control is dependent on; correct

summarisation of activities at the tactical and operational levels, gathering and

analysis of environmental information (price trends, competitors' actions, political factors and so on), setting of long term policies on materials and inventory, long

term price agreements and contracts perhaps involving exchange deals or barter. I

2.3 Functions Of Management

A useful way of grouping the functions of management is into the following

categories:

o PLANNING:- all activities leading to the formulation of objectives or goals and deciding upon the means of meeting them, behavioural processes where a


manager influences others in a group to contribute voluntarily to the

achievement of objectives by gaining their commitment.

o MOTIVATION & LEADERSHIP: - behavioural process where a manager influences others in a group to contribute voluntarily to the achievement of

objectives by gaining their commitment.

o ORGANISING & CO-ORDINATING: - determining the necessary

activities, structures and responsibilities and the synchronising and synthesising of activities, responsibilities and structures to achieve the plans.

o CONTROL: - a monitoring process whereby actual results are compared with

planned results in order to bring activities in line with plans or to amend the plans.

o DECISION MAKING:- This brings together all the other functions

mentioned above. This is the use of information in determining progression or resolution of problems or resolution of bottlenecks in business operation.

Decision making takes place within each of the above categories.

UNIT 3: Hardware

3.1 The Computer

Computer hardware technology constitutes the underlying foundation for the firm’s Information Technology (IT) infrastructure

Other components of IT infrastructure – software, data and networks – require

computer hardware for their storage or operation. We begin with discussing the pivotal

hardware device; the computer.

3.1.1. ANALOGUE COMPUTERS

An analogue computer is an electronic device that accepts physical quantity

inputs and processes that input as data. Examples of physical forms treated as data for processing include movement, hydraulic pressure, light, voltage

fluctuations and sound. Analogue computers take up the inputs and convert them

to a continuous representation for display or conversion to another form.

3.1.2. DIGITAL COMPUTERS

Digital computers refer to a type of computer that converts physical

representations of an electromagnetic state to a pre-agreed standard discrete number representation. (usually 1 and 0). Therefore a high/low or on/off state or

an open/closed state of particular circuits and devices are used to represent the

data to be processed. Digital electronic computers for the vast majority of

computers used for modern commercial data processing and information generation tools. Digital computers are designed to make the interpretation of the

on and off states rapidly providing the basis for potential to process large sets of

data in very small time intervals.

3.2 History Of Computers

"Who invented the computer?" is not a question with a simple answer. The real answer is that many inventors contributed to the history of computers and that a computer is a

complex piece of machinery made up of many parts, each of which can be considered

a separate invention. From the earliest simple devices that were developed to perform mathematical calculations to the programmable computers which are a matter of


private study and will not be mentioned here. However, mentioned here is the recent

history of computers leading to the current form of digital electronic computers.

A generation refers to the state of improvement in the development of a product. This term is also used in the different advancements of computer technology. With each

new generation, the circuitry has gotten smaller and more advanced than the previous

generation before it. As a result the miniaturization, speed, power, and memory of

computers have proportionally increased. New discoveries are constantly being developed that affect the way we live, work and play increasing productivity and

arguably a higher quality of life. After all who would claim to have a better wellbeing

if they had more strenuous activities to perform to earn their living. FIG. 4 A Summary of the Computer Generations

3.3 Types Of Computers

Types Of Computer Systems, Structure Of Computer Systems, Central Processing

Unit

(CPU), Data Representation.

3.4 General categories of computer systems

i) Supercomputer: These are the most powerful computers. Have enormous

storage capabilities and are several times faster and more powerful than

mainframes. Achieve high performance levels by using parallel

processing/multiprocessing (multiple processors work on the same problem at the same time by breaking the problem into pieces. Uses include high speed,

number-crunching military and scientific tasks, genetics research, weather

forecast, astrological simulations large time-sharing networks and very complex engineering application.

ii) Mainframe: have huge data storage capacities, very fast processors and are

powerful. They also have very large memory capacities. Process hundreds of different programs, handle massive amounts of data, respond to hundreds of


different users, and coordinate hundreds of peripheral all at the same time.

Used to solve engineering problems requiring many calculation in aircraft

manufacturing and petroleum engineering, by banks to process checks, deposits and other account information

iii) Midrange/Minicomputer Computer: middle-size computer capable of

supporting the computing needs of small organizations or of managing

networks of other computers. Used In systems for university, factories, or research laboratories. A new type of minicomputer also referred to as servers

are designed to enable and facilitate communications in local are networks and

file sharing. iv) Personal Computer (PC)/Microcomputer : come in a wide assortment of

sizes and have a variety of uses. Classified according to size and use: pocket,

hand-held/palmtop, personal digital assistants (PDA), smart phones, notebook, laptop, portable, transportable, desktop and floor standing. They are also

classified according to where and how they are used: home, personal,

professional, workstations, and multi-user, the latter being very powerful and

designed to support several users at a time.

v) Wearable: smallest computers. Used in watches, tiny electronic pagers and

some innovative clothing etc. The above stated categories of computer systems

types based on capacity are hard to identify in practice. With the miniaturisation and compacting of powerful processors in smaller devices it is

not uncommon to have dual categories of computer type to avoid confusion.

The primary focus however is where and how these computers are put to use.

3.5 Productivity and Business on the Go

Portable microcomputers such as PDA’s, Palmtops, Handhelds, Smart phones and even laptops have enable the creation of new business models and the re-engineering

of existing ones. The ability of these devices to integrate mobile communications and

data networks raise interesting levels of task accomplishment and productivity. Emergent from these technological advancements have been new business models or

modes of business information delivery.

3.6 Architecture Of Computer Systems

The computer system consists of six major components:

1) The Central Processing Unit (CPU): manipulates data and controls the other parts of the computer system

2) Primary storage: temporarily stores data and program instructions during

processing (RAM – Random Access Memory)

3) Secondary storage: stores data and instructions when they are not used in

processing 4) Input devices convert data and instructions for processing in the computer e.g.

keyboard, computer mouse, touch screen etc.

5) Output devices present data in a form that people can understand e.g. printers,

audio output video display monitors etc. 6) Communication devices control the passing of information to and from

communication networks.


FIG. 5 Computer Systems Illustrative Diagram

3.6.1. COMPUTER REPRESENTATION OF DATA

A representation is a form used to express a particular object, character, entity etc.

In order for information to flow through a computer system and be in a form suitable for

processing, all symbols, pictures or words must be reduced to a string of binary

digits (BIT)

Bit: an acronym for binary digit represents the smallest unit of data in a computer system. Can only have one of two states, representing 0 or 1. The location of the

stored Bit is called the CELL.

Byte: a string of bits, usually 8, used to store a character in a computer system.

The computer representation in ASCII for

the name Alice is as follows: -


Computer hardware manufacturers have developed standard binary codes to represent data in

the computer. Two common codes are Extended Binary Coded Decimal interchange Code

(EBCDIC) and American Standard Code for Information Interchange (ASCII): o Extended Binary Coded Decimal interchange Code (EBCDIC): binary code

representing every number, alphabetic character or special character with eight

bits, used primarily in IBM and other mainframe computers.

o American Standard Code for Information Interchange (ASCII): a seven- or eight-bit binary code used in data transmission, PCs and some large computers.

How then can a computer represent a picture? The computer stores a picture by creating a

grid overlay of the picture. Each single point in this grid or matrix is called a pixel (picture

element) and consists of a number of bits. The computer then stores this information on

each

pixel. TABLE 1: Examples Of ASCII & EBCDIC Codes

3.6.2. COMPUTER STORAGE CAPACITY

Data stored in computer systems or computer data storage devices follows the

following

units of storage. These allow the quantification of storage location magnitudes and

capacity. TABLE 2: Data Capacity Standard Units

Byte 8 bits (ASCII)

3.6.3. THE CPU AND PRIMARY STORAGE

Central Processing Unit (CPU): manipulates data and controls the other parts of

the computer system. The CPU contains an arithmetic-logic unit and a control unit.


a) Arithmetic & Logic Unit: component of the CPU performs the computer’s

principle logic and arithmetic operations.

b) Control unit: component of the CPU that controls and coordinates the other parts of the computer system. Reads a stored program, one instruction at a

time, and directs other components of the computer system to perform the

required tasks. Machine cycle: series of operations required to process a

single machine instruction, measured in microsecond (one-millionth of a second) or nanosecond (one-billionth of a second). Another measurement of

machine cycle time is by MIPS (millions of instructions per second)

c) Primary storage: part of the computer that temporary stores program instructions and data being used by instructions. Random Access Memory

(RAM) is primary storage of data/program instructions that can access any

randomly chosen location in the same amount of time. RAM is volatile (its contents will be lost when the computer’s electric supply is disrupted by a

power outage or when the computer is turned off.

i) RAM composed of semiconductors – integrated circuit made of printing

thousands and often millions of tiny transistors on a small silicon chip.

ii) Read Only Memory (ROM) : semiconductor memory chips that contain

program instructions; can only be read from; can not be written to.

3.6.4. MICROPROCESSORS AND PROCESSING POWER

Microprocessor: very large-scale integrated circuit technology that integrates the computer’s memory, logic and control circuits for an entire CPU onto a single chip.

Computer processing power depends, in part, on the speed of the processors.

Microprocessor capabilities can be gauged by the following factors:

i) Word length: the number of bits that a computer can process at one time.

The larger the word length, the greater the computer’s speed.

ii) data bus width: the number of bits that can be moved at one time between

the CPU, primary storage and the other devices of a computer iii) Cycle speed: the sequencing of events/steps in a computer so that events

logically follow each other. The control unit sets a beat to the chip and this

beat is established by an internal clock and measured in megahertz (MHz = 1 million cycles per second) – a measure of cycle speed or the pacing events

in a computer. TABLE 3: Examples of Microprocessors


3.6.5. MULTIPLE &PARALLEL PROCESSING

Multi-Processing: Many computers use multiple processors to perform their

processing work. For example, PCs often use a co-processor to speed processing by

performing specific tasks such as mathematical calculations or graphics processing so that the CPU is free to do other processing . Processing can also be speeded by

parallel processing and massively parallel computers.

Parallel Processing: Type of processing in which more than one instruction can be processed at a time by breaking down a problem into smaller parts and processing

them simultaneously with multiple processors massively parallel computers:

computers that use hundred or thousands of processing chips to attack large

computing problems simultaneously

UNIT 4: Input Devices Input Devices: VDU and keyboards, WIMP-Windows, Icons, Mouse, Pointer,

Optical

Character Recognition (OCR), Magnetic Ink Character Recognition (MICR), Bar

coding, Point-Of Sale (POS) system, Kimball tags, key-to-Disk/ Tape system, voice

data input.

4.1 Human Computer Interaction

Humans interact with computers largely through input and output devices. Input and output devices are analogues to the human senses meant and adapted to assimilating

stimulus from the environment. They are a means but which data and information are

supplied to the CPU and conversely feedback relayed. . Input devices gather data and

convert them into electronic form suitable for use by the computer. Whereas output

devices display data after they have been processed. TABLE 4: Device and Descriptions


4.2 Data Capture and Entry

4.2.1. POINT-OF SALE (POS) SYSTEM

POS: essentially an electronic cash register which is linked to a computer or

which records data onto a cartridge. In its simplest form, it may simply transmit

the details of a transaction to the computer for processing but the more complex

terminals can communicate with the computer for such purposes as checking the

credit position of a customer, obtain prices from file and ascertain the availability of stock.

4.2.2. BAR-CODED AND MAGNETIC STRIPS

Data can be recorded on small strips which are read optically or magnetically.


Optical reading is done by using printed bar codes i.e. alternating lines and spaces

which represent data in binary (used in supermarkets such as SHOPRITE).

Magnetic reading depends on a stripe of magnetic tape on which data has been encoded. The data is read by a “light pen” which is passed on the strip (e.g. ATM

cards, visas).

4.2.3. TAGS

The use of tags as a data collection technique is usually associated with clothing retailing applications although they are also used to some extent in other

applications. Uses a special code and data such as price of garment, type and size,

branch/dept are recorded on the tag.

4.2.4. DIRECT INPUT DEVICES

Voice Data Entry Devices: data can be spoken into these devices through

receptors such as microphones and other audible sound sensors and relayed to the CPU for

processing.

4.2.5. ON-LINE SYSTEMS

On-Line Systems: data collection in which the computer is directly linked to the source of the data

4.2.6. KEYBOARD ENTRY

One typical keyboard input device is the VDU (Visual Display Unit). The VDU is really a two devices in one; one for input, one for output. The VDU can receive

and display messages from the computer.

4.2.7. KEY-TO-DISK/ TAPE SYSTEM

This is a popular alternative to on-line systems in some organizations. key-to-

Disk/

Tape system are microcomputer-based systems which take in data from the VDU and store it on disk/tape.

UNIT 5: Storage Devices Secondary Storage Devices, Magnetic Tape, Magnetic Disks, CD-Roms,

Optical Disks

5.1 Secondary Storage Technology Relatively long term storage and non-volatile (retains data even when the computer is turned

off).

This type of storage is used to back up or store files and software for use at a later point in

time. This is the source of input for the memory (primary storage) during processing. This type

of storage is usually inexpensive and large amounts of data can be stored on these devices. The

following are examples of typical storage devices commonly used for bulk information storage

and back-up.

5.1.1. MAGNETIC DISK

A secondary storage medium in which data are stored by means of magnetized

spots on a hard or floppy disk.

i) Hard Disk Drive (HDD): magnetic disk resembling a metallic platter;

used in large computer system and in most PCs.


ii) Floppy disk: Removable and portable magnetic disk storage primarily

used with PCs. Disk technology is useful for systems requiring rapid

and direct access to data. iii) RAID (Redundant Array of Inexpensive Disks): disk storage

technology to boost performance by packaging more than 100 smaller

disk drives with a control chip and specialized software in a single large

unit to deliver data over multiple paths simultaneously.

5.1.2. MAGNETIC TAPE

Inexpensive, order secondary storage medium in which large volumes of

information are stored sequentially by means of magnetized spots on tape. They are also referred to as sequential access storage devices (SASD) as in order to

find an individual record stored on magnetic tape, the tape must be read from

beginning up to the location of the desired record.

5.1.3. FLASH DRIVES AND MEMORY CARDS

A flash drive, related to a solid state drive, is a storage device that uses flash

memory rather than conventional spinning platters to store data. Flash drives

tend to physically imitate conventional hard drives in size, shape, and interface

so that they may act as a replacement for hard drives. A memory card or flash

memory card is a solid-state electronic flash memory data storage device used

with digital cameras, handheld and laptop computers, mobile phones, music players, video game consoles, and other electronics. They are very portable

hence their application with portable device data storage.

5.1.4. OPTICAL DISK

These use laser technology to store massive quantities of data in a highly

compact form by burning grooves in an electrostatic plastic. Examples of

optical disks are CD-ROM, CD-R,CD-RW, DVD, DVD-R, DVD-RW,

BLUE-RAY, HD-DVD

5.2 New Storage Alternatives:

Storage Area Networks (SANs) and On-Line Storage Service Providers (SSPs)

5.2.1. SAN:

A high speed network dedicated to storage, which connects different kinds of storage device, such as tape libraries and disk arrays. Can be expensive and

difficult to manage.

5.2.2. SSP:

third-party provider that rents out storage space to subscribers over the Internet, allowing customers to store and access their data without having to purchase and

maintain their own storage technology physically.

5.3 Output Devices

Impact Printers, (Dot Matrix, daisy wheel), Xerographic printer (laser printer),

Thermal printer, liquid ink printers, graph plotter, computer output on microfilm

(COM), fax, VDU, voice data output.

Humans interact with computers largely through input and output devices. Input

devices gather data and convert them into electronic form for use by the computer whereas output devices display data after they have been processed.


5.3.1. PRINTERS

Printers produce a printed hard copy of information output. They include impact printers (such as dot matrix printers) and non impact printers (laser, inkjet and

thermal transfer printers) Print speeds tend to be expressed in terms of

cps(character per second) or lpm (lines perminute) or ppm (page per minute) Low Speed Printers (print speed 10cps to approx. 300lpm)

Impact or non-impact Printers: impact printers hit inked ribbons against paper

whereas nonimpact printers use other methods of printing e.g. thermal or

electrostatic. Most impact printers are noisy. 1) Dot Matrix impact characters printers:

2) Daisywheel printers:

3) Thermal printers: 4) Inkjet printers:

High-Speed Printers ( print speed typically 300 lpm – 3000 lpm)

Page printers: the printers print an “image” of a whole page at a time. The image

may consist of conventional print, diagrams, pictures, or a combination of these.

These printers are also known as optical printer, Laser printers or Xerographic

printers

5.3.2. MICROFORM RECORDERS

Microforms are photographically reduced documents on films. There are two

types:

1) Microfilm – 16mm roll film

2) Microfiche – sheet film 105mm x 148mm

Both types are produced in the same manner.

Output is written onto magnetic tape, which is often fed into a machine called a microfilm recorder which reads the magnetic tape and copies the data onto

microforms. The information can subsequently be inspected by using a viewer

which projects onto a screen. Full-size copies can be printed if required. This technique is useful when large volumes of information are used internally, since

economies can be made in stationery cost and storage

space. It is usually referred to as a COM (Computer Output on

Microfilm/Microfiche).

Storage Capacity : a typical 16mm roll will hold the equivalent of 3000 A4

pages

5.3.3. GRAPH PLOTTERS

These devices provide a completely different form of output and have a variety

of

applications. Two basic types are: 1) Flat bed type: the pen moves up, down, across or side to side

2) Drum type: the pen moves up, down and across. The paper provides the

sideways movement.

EXERCISE 1 1. What are the distinguishing factors of the present, or fourth generation, computers? 2. Explain in detail how the control unit, of the central processing unit (CPU)

functions.

3. List the building blocks that make up digital computers, and describe fully the data and instruction flows that occur between them.


4. Distinguish between the contents of a memory cell and the address of a memory

cell.

5. Distinguish between a byte and a word. Distinguish between a byte and a bit. 6. How many bits are in the following : -

a) 61Bytes

b) 62KBytes

c) 63Mbytes 1 Byte = 8 Bits

1 KByte = 210 Bytes

1 Mbyte = 1000 Kbytes

7. Convert the following decimal numbers to (a) Binary (b) Octal

a) 456

b) 34 c) 78

8. Convert the following binary numbers to (a) Decimal (b) Octal.

a) 100101011

b) 11001 c) 1111111

9. Formulate a coding system for the first ten letters of the alphabet using binary

representation in ascending order. 10. Using odd parity give the new complete representation of your characters in (9)

above.

11. Give four methods of data/ instruction input to a computer, which incorporates the use a visual display unit (VDU). Explain in detail how each of your methods

achieves data input.

12. Mention three commercial applications of optical character recognition (OCR) as a means of data/information input associated with computerized systems.

13. What is a Computer peripheral device?

14. Printers are widely used computer output devices. Mention five types of printers

describing:- a) How printing is achieved.

b) Usual application of the printer type.

c) Relative cost d) Advantages or disadvantages of the type of printer or printing mechanism.

15. An organisation with a large data set of particularly paper document type wishes to

store these data sources in a more compact and easy to access data storage media or format. Discuss the possible considerations of at least three alternatives citing

the pro’s and con’s of each alternative.

16. What is microfilm and what organisations make use of microfilm technology?

Give examples.

UNIT 6: Communications Data Transmission: Data transmission systems, Data Switching; Simplex,

Duplex and

Half Duplex transmission; data transmission equipment (Modems, Acoustre

couplers,

multiplexers), protocol.


6.1 Data Transmission

Data transmission is the process of moving data from one location to another. It is also

the movement of data from one entity to another. The entities being the communicating devices.

6.1.1. DATA TRANSMISSION SYSTEMS

A data transmission systems consists of five major components: the sending

device (computers, terminals, microcomputers, mainframe), the sending/receiving communications interface device (modem, multiplexer, front-

end processor, fax) , the communications channel (phone cables, coaxial cables,

fibre optic cables, satellites, microwaves systems), the receiving device(computers) and communications software. The data transmission system

is also referred to as the communications model. FIG. 6 The communications model

6.1.2. SIMPLEX, DUPLEX AND HALF DUPLEX TRANSMISSION

Transmission is possible in three modes:

a) Simplex: transmission is possible in only one direction. b) Half Duplex: transmission is possible in both directions, but not

simultaneously.

c) Duplex: transmission is possible in both directions simultaneously

6.1.3. INTERFACE DEVICES

Transmission Interface devices are responsible for the conversion of

transmission signals to a form that can be transmitted over a communications

channel. They form a sort of bridge between the transmitting device and the channel of transmission.

i) Modem (Modulator-Demodulator) : coverts digital signals to analogue

signals suitable for transmission through the cables (primarily telephone lines) at the sending point and from analogue signals to digital signals at

the receiving point.

ii) Acoustic couplers: cheaper alternative to modem, which makes it possible to use an ordinary telephone handset for transmission. This is

suitable only for low speed transmission.

iii) Multiplexers: deals with the routine work of handling incoming and outgoing messages when a number of terminals/computers are linked to

a central computer. This is order to facilitate the use of one transmission

line by several transmitting computers. The multiplexer bundles several

signals and sends them at once.

6.2 Network architectures: layers, protocols

6.2.1. COMPUTER NETWORK STANDARDS

A computer network is an interconnection set of two or more computers.

Complexity in computer networks is reduced by organizing the network as a


number of layers, each layer being built upon its processor. Associated with each

layer is one major function or possibly several related functions but complexity

is reduced by separating essentially different functions into different layers. An architectural model developed by the International Standards Organization

(ISO) is frequently used to describe the structure and function of data

communications protocols. This architectural model, which is called the Open

Systems Interconnect Reference Model (OSI), provides a common reference for discussing communications. The terms defined by this model are well

understood and widely used in the data communications community - so widely

used, in fact, that it is difficult to discuss data communications without using OSI's terminology. The OSI Reference Model contains seven layers that define

the functions of data communications protocols. Each layer of the OSI model

represents a function performed when data is transferred between cooperating applications across an intervening network. Figure 5 identifies each layer by

name and provides a short functional description for it.

Looking at this figure, the protocols are like a pile of building blocks stacked one

upon another. Because of this appearance, the structure is often called a stack or

protocol stack.

FIG. 7 The OSI Reference Model

Every protocol communicates with its peer. A peer is an implementation of the

same protocol in the equivalent layer on a remote system; i.e., the local file transfer protocol is the peer of a remote file transfer protocol. Peer-level

communications must be standardized for successful communications to take

place. In the abstract, each protocol is concerned only with communicating to its peer; it does not care about the layer above or below it. Although the OSI model

is useful, the TCP/IP protocols don't match its structure exactly. Therefore, in our

discussions of TCP/IP, we use the layers of the OSI model in the following way:

6.2.2. TCP/IP PROTOCOL ARCHITECTURE

While there is no universal agreement about how to describe TCP/IP with a layered

model, it is generally viewed as being composed of fewer layers than the seven used

in the OSI model. Most descriptions of TCP/IP define three to five functional levels in the protocol architecture as follows.


FIG. 8 Layers in the TCP/IP protocol architecture

As in the OSI model, data is passed down the stack when it is being sent to the network, and up the stack when it is being received from the network. The four-

layered structure of

TCP/IP is seen in the way data is handled as it passes down the protocol stack from the Application Layer to the underlying physical network. Each layer in the stack

adds control information to ensure proper delivery. This control information is called

a header because it is placed in front of the data to be transmitted. Each layer treats all of the information

it receives from the layer above as data and places its own header in front of that

information. The addition of delivery information at every layer is called encapsulation. (See

Figure 6)

When data is received, the opposite happens. Each layer strips off its header before

passing the data on to the layer above. As information flows back up the stack, information received from a lower layer is interpreted as both a header and data.


FIG. 9 Data encapsulation

Each layer has its own independent data structures. Conceptually, a layer is unaware of the data structures used by the layers above and below it. In reality, the data

structures of a layer are designed to be compatible with the structures used by the

surrounding layers for the sake of more efficient data transmission. Still, each layer has its own data structure and its own terminology to describe that structure.

UNIT 7: Network topology

7.1 Introduction

A network topology is the pattern of links connecting pairs of nodes of a network. A

given node (Computer or Interface Message Processor) has one or more links to others, and the links can appear in a variety of different shapes. The simplest connection is a

one-way link between two devices. A second return link can be added for two-way

communication. Modern communications cables usually include more than one wire in order to

facilitate this, although very simple bus-based networks have two-way communication

on a single wire.

Network topology is determined only by the configuration of connections between nodes; it is therefore a part of graph theory. Distances between nodes, physical

interconnections, transmission rates, and/or signal types are not a matter of network

topology, although they may be affected by it in an actual physical network. FIG. 10 Network topologies


There are two main types of processing set ups. Centralised, decentralised and hybrid

processing. All of which are illustrated in FIG. 10.

7.1.1. CENTRALISATION

The star topology reduces the chance of network failure by connecting all of the

systems to a central node. When applied to a bus-based network, this central hub

rebroadcasts all transmissions received from any peripheral node to all peripheral nodes on the network, sometimes including the originating node. All peripheral

nodes may thus communicate with all others by transmitting to, and receiving from,

the central node only. The failure of a transmission line linking any peripheral node to the central node will result in the isolation of that peripheral node from all others,

but the rest of the systems will be unaffected.

A tree topology can be viewed as a collection of star networks arranged in a hierarchy. This tree has individual peripheral nodes (i.e. leaves) which are required

to transmit to and receive from one other node only and are not required to act as

repeaters or regenerators. Unlike the star network, the function of the central node

may be distributed. As in the conventional star network, individual nodes may thus still be isolated from the network by a single-point failure of a transmission path to

the node. If a link connecting a leaf fails, that leaf is isolated; if a connection to a

non-leaf node fails, an entire section of the network becomes isolated from the rest.

7.1.2. DECENTRALISATION

In a mesh topology, there are at least two nodes with two or more paths between

them. A special kind of mesh, limiting the number of hops between two nodes, is a

hypercube. The number of arbitrary forks in mesh networks makes them more

difficult to design and implement, but their decentralized nature makes them very

useful. This is similar in some ways to a grid network. A fully connected, complete topology or full mesh topology is a network topology

in which there is a direct link between all pairs of nodes. In a fully connected

network with n nodes, there are n(n-1)/2 direct links. Networks designed with this

topology are usually very expensive to set up, but have a high amount of reliability due to multiple paths data can travel on. This topology is mostly seen in military

applications.

7.1.3. HYBRIDS

Hybrid networks use a combination of any two or more topologies in such a way

that the

resulting network does not have one of the standard forms. For example, a tree network


connected to a tree network is still a tree network, but two star networks

connected together (known as extended star) exhibit hybrid network topologies. A

hybrid topology is always produced when two different basic network topologies are connected. Two common examples for Hybrid network are: star ring network

and star bus network

7.2 A Detailed look at specific network topologies

7.2.1. BUS NETWORK

A bus network is a network architecture in which a set of clients are connected

via a shared communications line, called a bus. FIG. 11 Bus network

There are several common instances of the bus architecture, including one in the motherboard of most computers, and those in some versions of Ethernet networks.

Advantages Bus Networks

o Easy to implement and extend o Well suited for temporary networks (quick setup)

o Typically the cheapest topology to implement

o Failure of one station does not affect others

Disadvantages Bus Networks

o Difficult to administer/troubleshoot

o Limited cable length and number of stations

o A cable break can disable the entire network o Maintenance costs may be higher in the long run

o Performance degrades as additional computers are added or on heavy

traffic o Low security (all computers on the bus can see all data transmissions on

the bus)

o One virus in the network will affect all of them (but not as badly as a star or ring network)

o Proper termination is required.(loop must be in closed path)

7.2.2. RING NETWORK

A ring network is a topology of computer networks where each node is connected to two other nodes, so as to create a ring. The most popular example is a token ring network. Ring

networks tend to be inefficient when compared to star networks because data must travel

through more points before reaching its destination. For example, if a given ring network has eight computers on it, to get from computer one to computer four, data must travel

from computer one, through computers two and three, and to its destination at computer

four. FIG. 12 Ring Network


It could also go from computer one through eight, seven, six, and five until reaching four,

but this method is slower because it travels through more computers.

Advantages of Ring Networks o All stations have equal access

o Each node on the ring acts as a repeater, allowing ring networks to span

greater distances than other physical topologies.

o Because data travels in one direction high speeds of transmission of data are possible

o When using a coaxial cable to create a ring network the service becomes

much faster.

Disadvantages of Ring Networks

o Often the most expensive topology

o If one node fails, the rest of the network could also fail o Damage to the ring will affect the whole network

o Often quite difficult to install

7.2.3. STAR NETWORK

Star networks are one of the most common computer network topologies. In its

simplest form, a star network consists of one central switch, or hub computer which

acts as a router to transmit messages. FIG. 13 Star Network

When applied to a bus-based network, this central hub rebroadcasts all transmissions

received from any peripheral node to all peripheral nodes on the network, sometimes

including the originating node. All peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the central node only. The failure of a

transmission line linking any peripheral node to the central node will result in the

isolation of that peripheral node from all others, but the rest of the systems will be unaffected.

Advantages of star networks

o Easy to implement and extend, even in large networks o Well suited for temporary networks (quick setup)

o The failure of a non-central node will not have major effects on the

functionality of the network.

o Reliable market proven system o No problems with collisions of Data since each station has its own cable to

the server/hub.

o Security can be implemented in the hub/switch.

Disadvantages star networks

o Limited cable length and number of stations

o Maintenance costs may be higher in the long run o Failure of the central node can disable the entire network.

o One virus in the network can affect them all.

o Depending on the transmission media, length limitations may be imposed from the central location used.


7.3 What is Ethernet?

Ethernet is a frame-based computer networking technology for local area networks

(LANs). The name comes from the physical concept of ether. It defines wiring and signalling

for the physical layer, and frame formats and protocols for the Media Access Control

(MAC)/data link layer of the OSI model. It has become the most widespread LAN

technology in use during the 1990s to the present, and has largely replaced all other LAN standards. FIG 13 below shows an interface device that is usually installed in the

CPU housing of a computer. FIG. 14 Network Card

UNIT 8: Network Types & Span Networks can also be categorised by the expanse, reach or span that they cover.

This is a significant categorisation as this enables relate to the unique technologies in use and other network characteristics.

PAN: Personal Area Network (PAN) refers to the short range of connectivity

associated with devices that only spans very short distances. In the wireless arena examples of PAN networks are Infra Red systems and Bluetooth. Examples of

Bluetooth and Infra Red can be experience inmost mobile phone devices.

LAN: Local Area Network (LAN); These are networks that span a fairly small

central area, building or a site. Offering more connectivity than a PAN and broader ranges and higher transfer capabilities. A typical example of LAN

systems would be Ethernet and WiFi . A WiFi hotspot is a wireless LAN i.e.

enables devices to connect to the network wirelessly. SAN: Storage area network (SAN) is a network designed to attach computer

storage devices such as disk array controllers and tape libraries to servers. A

network of storage disks. In large enterprises, a SAN connects multiple servers to a centralized pool of disk storage. Compared to managing hundreds of servers,

each with their own disks, SANs improve system administration. By treating all

the company's storage as a single resource, disk maintenance and routine backups

are easier to schedule and control WAN: Wide Area Network (WAN); Refers to the interconnected LANs that may

span a larger area than a site or building. A WAN is a geographically dispersed

telecommunications network. The term distinguishes a broader telecommunication structure from a local area network. WANs may even link

LANs in different towns.

MAN: Metropolitan Area Network (MAN); Synonymous with larger spanned

wireless networks that may cover an area of several kilometres in town to provide

a wireless network or access to the Internet. WiMAX is the wireless solution for

the next step up in scale, the metropolitan area network (MAN). A MAN allows areas the size of cities to be connected.


LHN: Long-haul networks carry a lot more data than any type of network, and

over much greater distances. allows the regeneration-site spacing to be extended

from 500 km to 2000 km. This ultra-long-haul application, therefore, introduces significant cost savings and reduces the per-kilometre cost of transmission

capacity.

8.1 Other Network Terminologies

FIG. 15 Modern Network Illustration

8.2 Data Communications Rates and Capability

Bandwidth, in computer science, amount of data that can be sent through a data-transmitting medium, such as a computer network, telephone line, or coaxial cable, in


a given amount of time. Bandwidth is usually expressed either as a transmission rate

called baud or in bits per second (bps). Standard telephone lines are analogue and

have a low bandwidth. They can only transmit data at a maximum speed equivalent to about 14,400 bps. All of the interconnected data transmission systems operated by

various telephone companies are known collectively as the Public Switched Telephone

Network (PSTN) or the Plain Old

Gateway: A device that allows for the translation and management of communication between networks that use different protocols or designs.

Router: A network device that connects two similar networks having the same network protocol. It also chooses the best path between two networks when there are multiple paths.

Packet Switching: Refers to protocols in which messages are divided into packets before they are sent. Each packet is then transmitted individually and can even follow different routes to its destination. Once all the packets forming a message arrive at the destination, they are

recompiled into the original message Telephone System (POTS). The PSTN is now updating the old network from analogue to digital. In addition, older copper telephone

wires that once made up the PSTN are being steadily replaced by fibre-optic cables.

Fibre-optic cable uses infrared and visible light pulses to transmit data down thin glass

or plastic fibres. This medium has several benefits including its high bandwidth, low susceptibility to interference, and relatively low cost.

Another comparatively fast medium with a larger bandwidth than PSTN is the

Integrated Services Digital Network, or ISDN. ISDN is a combination of fibre-optic technology and special phone service provided by telephone companies that allows for

digital audio and video transmission. Other data transmission media, such as the

coaxial cable used by commercial cable companies, can transmit data at more than 500,000 bps.


TABLE 5: Network Type & Transmission Rate

It is worth noting how much data can be transmitted using various technologies for better

management and business decision making. Availability of the technology and the consideration of the costs and benefits of their use are a crucial aspect of modern

management in any enterprise. More competitive and productive businesses have shown

that the massive infusion of communications and data transfer technologies into their mainstream operations has not only enabled their organisations to grow faster but also be

more competitive.


EXERCISE 2 1. What is the communications model and mention all it’s

components.

2. What are the roles of each of the component of the Data

communications model? 3. What are the primary reasons for networking among

computers and computer related devices? Giving real

applications relate your answers to justify the networks or type of networking achieved.

4. List the seven layers of the OSI reference model, and give a

description of the role of each layer in a single sentence. 5. Approximately how many minutes does it take to download

a 4Mbyte mp3 file on a fully enabled and connected mobile

device using a GPRS network to access the internet. Assuming there are no server delays and dropped packets

during transmission

6. Explain the meaning of these terms, in relation to

communications networks. i. Bandwidth.

ii. Multiplexing

iii. Broadband 7. Distinguish between Data Streaming and Downloading

and mention which technical terms are used to describe

them. 8. Mention five issues associated with wireless networking

and LAN Security.

9. What is meant by ‘connectivity’ in computer systems specifications?

10. List 5 ways a PDA can be used to access the Internet.

UNIT 9: Software Systems Software, Application Software, Utility Software, Acquisition of

software,

programming languages, basic programming principles.

9.1 Introduction

In Units 3 & 4 we dealt with or learnt about the physical components of a computer

system. At the core of these physical components are the instructions that are used to carryout

the processing. Basically, the hardware is controlled by a stored program, (in a form

that the computer has been built to understand) of what the computer is to do. Such a stored program is an example of computer software.

Software is defined as the set of programs (made up of instructions) that control the

operations of the computer system. The hardware is the “physical machine” behind

the operations of the computer and the software the “virtual machine”.

The software defines the character of the hardware (computer) and determines what

the computer as a whole is able to achieve. The software also determines what can be

achieved by the computer system. Software thus defines purpose, functionality and determines productivity computer utilisation.


9.2 Evolution of Computer Software

9.2.1. FIRST AND SECOND GENERATION LANGUAGES (1GL&2GL)

Initially all software was written in machine language. This is the form in which any instruction has to be in before actual execution takes place. Each instruction

in a machine language program must be expressed in the precise form that the

particular computer has been built to understand. No further translation is carried

out beyond this stage. The machine language version of instructions is thus referred to as the first generation language. Computer software developers

quickly created assembly languages that used the computer itself to perform

many of the tedious aspects of programming in machine language. This level of programming is known as the second-generation language. An assembler is

software coded in 2GL to convert 2GL Programs to their equivalent machine

version (1GL). The computer will thus under the control of the assembler convert source code into object code. (2GL to 1GL).

9.2.2. THIRD AND FOURTH GENERATION LANGUAGE (3GL&4GL)

Both the machine and assembly language programming requires the programmer to think like the computer in terms of individual instructions. With 3 GL’s and

4GL’s, the programmer uses a language that is relatively easy for humans to

learn and use. However the subsequent conversions will result in more code. As Illustrated in the example below: -

10 machine language instructions per 2 GL instruction.

100 machine language instructions per 3 GL instruction. 1000 machine language instructions per 4 GL instruction. Note: The gravity of the implications of the illustration will be apparent when we write our own 3 GL code!

The 3 GL and 4 GL are hardware independent. Implying that programs

developed does not necessarily take into consideration the subsequent translation in a lower platform. This allows different programs to run on different lower

platforms.

4GL’s are also called procedural languages because they express program logic by a step-bystep procedure devised by the programmer to accomplish a task or

solve a problem.

FORTRAN, COBOL, BASIC, PASCAN, C, ADA are examples of 4 GL’s

9.3 General types of Software

There are three main categories of software, SYSTEMS, UTILITY and APPLICATION

SOFTWARE.

9.3.1. SYSTEMS SOFTWARE

These are also referred to as support software and are meant to carry out computer device management tasks. They also enable the effective and efficient

use of computer system or hardware resources. Systems Software is also

responsible for managing all the other Software running on the computer system.

They are meant to be the linking software between application software and the

hardware. Examples OS, Communication software.

9.3.2. UTILITY SOFTWARE

Utility Software can also be referred to as specialised systems software. They mostly deal with data and file management tasks. Examples of utility software

are media converters and database management systems. It must be pointed out

that some of this functionality is actually bundled with operating systems.


9.3.3. APPLICATION SOFTWARE

These software directly interact with the user to carry out user defined or designed tasks. All activities of processing data are carried out in conjunction

with application software. The application software is the actual interface

between user and machine (IN TERMS OF CARRYING OUT USER DEFINED TASKS). Examples of application software are spreadsheets, word processors,

statistical software, web browsers etc.

9.4 More on Systems Software

9.4.1. OPERATING SYSTEMS

An Operating System is software intended to reduce the intervention of programs being run by human operators. It controls all the activities of the computer

system (programs and hardware) and coordinates resource utilization. The

operating system is the most important type of systems software and manages all the input and output, processing and storage devices to maximize systems

performance. The operating system is the core software component of your

computer. It performs many functions and is, in very basic terms, an interface

between your computer and the outside world. In the section about hardware, a computer is described as consisting of several component parts including your

monitor, keyboard, mouse, and other parts. The operating system provides an

interface to these parts using what is referred to as "drivers". This is why sometimes when you install a new printer or other piece of hardware, your

system will ask you to install more software called a driver.

A DRIVER is a specially written program which understands the operation of the device it interfaces to, such as a printer, video card, sound card or CD ROM

drive. It translates commands from the operating system or user into commands

understood by the component computer part it interfaces with. It also translates responses from the component computer part back to responses that can be

understood by the operating system, application program, or user. The below

diagram gives a graphical depiction of the interfaces between the operating

system and the computer component.


FIG. 16 Device Management

Administrative Functions of an Operating System

o Scheduling jobs (multiprocessing, multiprogramming, multitasking) o Allocating memory space (virtual memory)

o Tracking all application programs and systems software

o Maintaining operating status

o Communicating with operators o Reduce resource idle times

o Minimize amount of manual intervention when processing data

Features of an Operating System o Interface to facilitate communication with the user (GUI)

o Plug-and-play facility

- Examples of operating system: LINUX, UNIX, OS/X, MS-DOS, Windows XP, Windows Mobile 6.0, Red Hat, Symbian OS.

9.4.2. UTILITY SOFTWARE

These handle common file handling routines, data manipulation and housekeeping tasks that are undertaken by the computer. Examples of utility software, DBMS,

media conversion programs

9.4.3. COMMUNICATION SOFTWARE

This software is part of the communications model. They are responsible for handling the communications that take place between computerized systems. They

handle data traffic, transmission frequencies and any other tasks that facilitate the

communication of data and information between systems. They will in most case be harboured by the front end processors (Servers) or routers and other hardware

performing the task of device communication support.

9.4.4. DATABASE MANAGEMENT SYSTEMS (DBMS)

These are utility software that form part of the systems software. They are mainly in

programs that organize the way data is stored on a computer. The DBMS facilitates

data independence. That is the way data is stored on a computer will be independent of how is it viewed. A DBMS also enables efficient data retrieval techniques from


large sources of data (database). Examples of DBMS’s: ORACLE, MS Access,

MySQL.

9.5 Operating System Enabled Functions

In fulfilling the main operations of providing efficient resource utilization the

operating system has been developed to perform this task through a number of concepts (activities) being multiprogramming, multiprocessing, time-sharing and

virtual memory.

9.5.1. MULTIPROGRAMMING

The operating system makes it possible to overlap input and output operations with

processing time. This is very important because the time required to perform an I/O

operation is quite large as compared to time required to execute an arithmetic

instruction. [e.g. 100 000 arithmetic operations= Time Taken to read single Record] Thus it would be inefficient to leave the CPV idle while an I/O operation is being

completed.

9.5.2. TIME SHARING

This is similar to multiprogramming. Multiprogramming is event driven whereas

time sharing is time driven. Time-sharing is the usual mode of operations when large

numbers of users are simultaneously using a computer. Thus the user of a program is allocated a small portion of CPU time. This portion is called a time-slice.

9.5.3. MULTIPROCESSING

Multiprocessing is the incorporation of more than one processor to carry out task accomplishment. This it is simply the use of more processors to speed the time taken

to carry out complex operations or even carry out several complex tasks by assigning

different processors to the task.

9.5.4. VIRTUAL STORAGE

For any program to run it must be placed in Memory for execution. Programs and

software are usually much larger than the space available in Memory. Thus virtual

storage is a mechanism that only stores portion of the programs being executed at a particular point in time. A portion of the program under execution is placed in

memory making it appear as though the entire program is in memory and is being

executed. [the page concept]

UNIT 10: Acquisition of Software Acquisition of Software is an integral part of ensuring that any computing hardware

purchased performs the required tasks. Acquisition of Software is the full life cycle

of activities performed in order to receive or possess the desired Software product(s). An organization ( or individual) may choose to:

a) Develop their own Software in-house, or

b) Acquire ‘off-the-shelf’ packages, or c) Contract a Software house to develop the required software on their behalf (tailor

made software or modified software).


Note: There are two kinds of Application Software in relation to their acquisition: -

� General-purpose software and

� Specific-purpose software

General-Purpose software is usually purchased ‘off-the-shelf’ and is intended to suit a wide spectrum of users. A number of

frequently performed tasks are usually packages and provided as general-purpose software. These form the majority of ‘turn-key’

software packages.

Specific-Purpose software on the other hand is made or tailored to suit particular users or organizations. Requirements are

specified that meet an organizations needs and software developer’s produce the required software. These are more expensive and

less reliable than general-purpose software. Factors influencing the decision to acquire special purpose software include

availability of required software and uniqueness of operations. Special purpose software can also be produced in-house or a

software house contracted to develop it.

10.1 In-House Developed Software

As the name suggests, this is a scenario in which software is developed or coded by

members of staff in the particular organization that will use it. This requires the

availability of ‘suitably’ qualified staff to meet the software requirements that have been stipulated. In

House development is often carried out by large organizations that have either have

unique needs at their establishments or for some reason prefer to. Another trigger to in-house development is when the available software does not meet the user

(organizational) requirements.

ADVANTAGES OF IN-HOUSE SOFTWARE DEVELOPMENT INCLUDE: - o Will suit directly the needs of the users (tailor made).

o Less prone to corruption by other malicious software (viruses)

o Control over improvements, modifications or upgrades.

o Enhances the protection of trade secrets.

DISADVANTAGES OF IN-HOUSE SOFTWARE DEVELOPMENT INCLUDE: -

o Time Consuming. o Cost Implications

o Availability of Qualified staff.

o Quality Of the Software o Reliability of developed software may be low.

o Interaction with other software may be poor or difficult to implement.

10.2 Off-The-Shelf Software:

Also referred to as canned software provide a ready to use turn-key type of

software. Software vendors or software houses offer these software at a fee or provide the

intended recipients a license to use these software for a period of time. Thus the

users are either sold a license to use the software over a period of time or offered a copy of the software to acquire and use indefinitely. The Advantages and

disadvantages are of acquiring off-the-shelf software are intuitive.

10.3 Out-Sourced Software Development

This refers to a scenario in which a software development house is contacted to

develop the sought software. This may include outright development to modifications made on some existing software depending existing legalities of the

software to be modified. A variation of Out-Sourced development is the having

already existing software made to suit a client

(Tailor-Made or Modified Software).


10.4 FOSS (Free and Open Source Software)

10.4.1. FREEWARE:

This is software that is made available to acquire without the need for outright purchase or paying to use the software. The publishers of freeware allow the

redistribution andduplication of the software freely.

10.4.2. OPEN SOURCE SOFTWARE:

This is software whose publishers have made the source code available for anybody to alter without the need of a licence or agreement to do so. This

enables large groups of independent programmer to make contribution on

software project to develop robust and reliable freely available software. The programmers and publishing housing distributing this kind of software earn

money from consultation and end user support programs.

10.4.3. WEBWARE:

This kind of software is not installed directly onto a user’s computer but can be

accessed and launched remotely on servers on the Internet. Most Webware is

still in test phase and available to use without charge. An example Webware is Google documents published by Google laboratories.

10.4.4. SHAREWARE:

Similar to Webware in execution except shareware is hosted and run on LAN’s and

administered centrally to be accessed (shared) by users with machines

connected to the LAN. However, acquisition of most shareware is still primarily

through purchase agreements.

Advantages of shareware include minimised licensing costs as a single version

of that software can be loaded on a single host computer and others (agreed upon

number) on the LAN are allowed to use or share it without licence violation.

Examples of shareware include network administrator tools such as network

based anti-virus applications software.

10.4.5. GROUPWARE:

This type of software is specially designed to enable or allow groups of users to

collaborate their work efforts. Examples of applications are collaborative tools such as group decision support systems. These are also run on networked

computer with an emphasis on collecting and combining effort of all members

on the network.

10.5 Acquisition Method Factors

Which route to take for software acquisition and what options to consider stem from a long

list of considerations, some of which are presented below: -

i. Company /Organization size/ Complexity of Organization. ii. Availability of qualified staff.

iii. Application sought (unique or otherwise)

iv. Is the Software for the task available? v. Cost implications (Licensing and Purchase)

vi. Does it adequately meet organization needs?


vii. Operating System in use.

viii. Hardware specifications requirements.

ix. Other software installed on the machines and the need for inter-operability and coordination.

x. Consideration of the pros and cans of each type of Software against the

alternatives.

EXERCISE 3 1. What constraints are placed by the limitations of memory

in current computer?

2. What are the cost and performance issues associated with

computer memory?

3. What is software acquisition?

4. What points of consideration does a relatively large

organisation encounter when attempting to acquire

software? 5. List any 10 currently available Webware applications.

6. What is Open source software?

7. whatWhat are the ethical, commercial and social issues concerned with the duplication of software?

8. Selecting the right operating system to handle your desktop

applications is easy, right? Not necessary. Even though

your operating system decision boils down to three

common operating systems environments – Windows,

DOS, Unix – the issues surrounding the right operating

system are far more complex. When an organization decides to standardize its operating system it has to

examine not just what would save most money, but kind of

work each department does and what kind of work it might be doing in future. Changing an operating system impacts

the organization as a whole and each individual employee.

Switching operating systems isn’t a simple matter of changing programs. Window XP and UNIX operating

systems have distinct differences that an organization must

consider.

Required

i. What is an operating system? What role does it play in computer

operations?

ii. Describe the general features and functions of a standard operating system. Why is the selection task of an operating system complex?

ii. Research the difference between Windows XP and MS-DOS. How do these

differences affect the selection of an operating system?


UNIT 11: Licensing, Purchase and Use of Software A further understanding into the terms authors give for use of software they publish. This section enhances the student’s awareness of the obligation and terms of use software prescribed by publishing houses.

11.1 Introduction

Software is a unique type of product in terms of how it is distributed. It is also

differs from conventional products that the platform it is distributed on is not how

this product will be used. Software usually has to be installed onto the machine

before it is used. This creates a unique and interesting set of legal challenges.

Software is also a type of intellectual property and consent or approval has to be

sought before it can be used. (Recall section on FREEWARE & OSS). The creator of

these intellectual properties is at liberty to stipulate how their creation may be

used.

11.2 Intellectual Property

A product of the intellect that has commercial value, including copyrighted property

such as literary or artistic works, and ideational property, such as patents,

appellations of origin, business methods, and industrial processes. The legal rights

associated with inventions, artistic expressions and other products of the

imagination (e.g. patent, copyright and trademark law.)

11.3 Copyright

Also referred to as the right to copy. An incorporeal right granted by statute to the

creators of literary works and artistic productions whereby the creators are

invested for a specified period with sole and exclusive privilege of multiplying

copies or authorising performance of the same and publishing.

11.4 Trade Marks

A trademark or trade mark is a distinctive sign of some kind which is used by an

individual, business organization or other legal entity to uniquely identify the

source of its products and/or services to consumers, and to distinguish its products

or services from those of other entities. Certain words, phrases, names, designs,

icons, graphics or logos used on the Site may constitute trade marks, service marks

or trade names or other entities. The display of any trade marks on the Site does

not imply that a licence has been granted for any further use.

11.5 Licensing

A license is an arrangement under which an organisation (the licensor) grants

another organisation (the licensee) the right to manufacture goods, use patents,

use processes, or exploit trade marks within a defined market. Often used as an

international market entry method. It is also contractual agreements granting

permission for the use of intellectual property under specific conditions. Some

online licenses impose limits beyond what is covered under copyright law.

11.6 Acquisition and Use of Software

Software is a unique commodity in that it has to be copied onto the machine before

it can be used (Installed). Therefore unique conditions are prescribed by the


publishers of the software determining the usage and transferability of the

software even if it is paid for (See below).

11.7 End User Licensing Agreement (EULA)

This is synonymous with the agreements made by the publisher of software

granting the bearer permissions to load the software on their computer subject to

conditions. This may simply be an agreement made when the user/client accepts

the licensing agreement terms and conditions through the actual act of opening the

container/packaging that houses the software. This agreement may also be upheld

by activating the software itself. The user may opt out of the agreement by refusing

to open the container/packaging housing the software or refusing to activate it with

the subject conditions.

UNIT 12: Computer Appreciation Practical Orientation to applications software: Basic Computer Operation and File management, Word Processors, spreadsheets, Presentation tools, Accounting packages, Database Management Systems, Internet Browsers.

12.1 Computer Applications

Computers like any other tools are only as good as the use they are put to. This also

has a direct bearing on what software and applications that are installed on the

machine. In the subsequent sections emphasis will made on how to use the most

commonly available business and productivity tools. Most of the applications or

software under discussion is mass produced by software vendors and are widely

available. These are also referred to as canned software or canned

applications. These are synonymous with ready to use canned food products.

They are also referred to as turn key systems.

Below is a table of common productivity tools or business applications that may be

found with many computer systems. TABLE 6: Common Software Applications


To ensure an enhanced familiarity with some of the most widely used business

productivity tools, learning exercises given in the subsequent chapters on:

Spreadsheets, Word Processors, and Data Management Applications.

12.2 Basic file handling and Management

Here is a quick rundown of key terms or lingo associated with file management on

computers running the Microsoft Windows operating system platform.

12.2.1. KEY TERMS AND CONCEPTS


FIG. 17 A typical desktop setup

12.2.2. THE IMPORTANCE OF FILE ORGANISATION

Increases Tidiness: It is worth noting that computers in the hands of novices

and people who do not pay attention to how and where on the computer’s

storage device they save files risk creating a maze of files. Tidiness is not an

attribute to be shown only when handling physical files and documents

Makes Location of files easier: saving files and folders in appropriately named

locations using themes is an important computer etiquette whose benefits are

observed with ease of location of stored items.

Provides a system of grouping files:

Eases tracking of workflow and updates: when documents are being edited or

revised and previous or backup versions are preserved, careful naming and

relocation into appropriately named directories can help track the work flow.

12.3 Creating folders

Here are the essential steps required for folder creation.

� Navigate to the root directory or folder you wish to create the NEW folder.

� From the file menu select New>>folder

� Alternatively ‘RIGHT CLICK’ In the folder panel and select New>>folder from the

pop up box.

� Give the ‘new folder’ an appropriate name by ‘clicking once’ on its name or

‘RIGHT CLICK’ on the folder and select ‘Rename’.

� Give your folders ‘SENSIBLE’ names

� Have a theme for the folders

� Avoid Lengthy naming

� Documents, files and folders can be moved to these locations by ‘cutting’ them

from their current location and ‘pasting’ onto the destination folder.


Alternatively open both the origin folder and the destination folder and drag the

document or file to the destination folder.

UNIT 13: Word Processor Application This section contains practical exercise illustrating the simple editing routines that can be carried out to text to make it more presentable or to suit your preference or writing styles.

13.1 Introduction to Microsoft Word

For this exercise, you are required to have a computer with Microsoft Office 2000

installed. Most of these exercises can be carried out fairly easily on later versions of

Microsoft Office (Office 2003‐ Office 2007) FIG. 18 Visual Illustration of the GUI in Microsoft Office 2007

A Graphical User Interface (GUI) is the visual based interaction medium used to

access the commands of the application or software being run. GUI design is an

important aspect of the software as it determines how usable a software application

will be.

FIG. 19. Exercise 1: Editing Text


FIG. 20. Sample layout of text

After carrying out exercise 1 above, you should become aware of the main editing

functions available in this package. You will also become aware of the different

mouse buttons and the instructions they can be used to give in Microsoft Office

Word. We now move on to a more complex type of editing. However these

techniques can be used to save time and enable higher levels of productivity.

FIG. 21. Exercise 2: Applying Styles


FIG. 22. Layout for Exercise 2

The above exercise takes a editing a step further. It is intended to quickly and

uniformly apply formatting to text using predefined editing templates.


FIG. 23 . Exercise 3 Editing Styles

.

FIG. 24. Exercise 4: Auto Section Numbering

FIG. 25. Layout for Auto Numbering


FIG. 26. Exercise 5: Table of Contents Generation

UNIT 14: Spreadsheet Application This exercise illustrates the simple navigation routines that can be carried in a spreadsheet in an attempt to manipulate data. Editing of text can also be done using TOOLBAR shortcuts available at the top of the Graphical user interface which has similar toolbars with the other Microsoft office applications.

14.1 Introduction to Office Excel

Spreadsheets are a type of software that are meant to process (manipulate) stored

data.


Data can be stored on spreadsheets in locations called cells. These cells are portions

of the spreadsheet that are addressable and uniquely identifiable. They are given a

location in a reference to the x‐y scale or coordinate system. Here the X locations

are in alphabet and the Y locations on a numeric scale.

Prominent features and terms of Microsoft Excel: � Spreadsheet CELL Location Bar (NAME BOX).

� Cell editing (Entry Editing) location (FORMULA BAR).

� Workbook: This is the entire file that is opened as the work area.

� Worksheet: These are specific work areas within workbook ( Worksheet name at Bottom)

14.2 Exercise 1: Working with Workbooks and Worksheets. STEP 1: Launch Ms Excel

STEP 2: Open new workbook (FILE �NEW)

STEP 3: Type in the following data, starting in cell location A1. Simply click on the cell to start the

data entry

and press enter to navigate to the bottom cell. Navigation to another cell can also be done

alternatively with the arrow keys: ‐

STEP 4: SELECT ALL THE CELLS containing data and copy. Selecting is done the same way as

in other Microsoft applications software. Only this time it’s the entire cells and their contents being

selected.

STEP 5: Change worksheets and paste the data anywhere on the new sheet. [NOTE: a new

workbook will have

a default number of worksheets e.g. SHEET1, SHEET2, SHEET3].

STEP 6: Return to original sheet with copied Data and Click on an empty cell. [The highlighted cell

has a darker

border].

STEP 7: Press ‘delete’ or Escape (Esc) on the keyboard. [This clears the copy ‘operation’].

NOTE 1: Always remember to clear an operation, as Ms Excel will not do this automatically.

NOTE 2: All file saving operations are exactly the same in Ms Excel.

CONCLUSION: You have just worked with Data on worksheets, which you have imported by

copying and

pasting from an existing document (workbook). You have also copied data onto different worksheets

in the

same workbook.

14.3 Exercise 2: Editing Existing Data Editing of text/data in the cells can be done in the same manner as Ms Word. Alterations to the data

however are done slightly differently.


STEP 1: On an existing sheet in an Open workbook. Place the cursor on the cell to alter or modify

[or navigate in with the cursor. If address of cell is known it can be typed in Address bar e.g. (A13)].

STEP 2: Double click on the CELL and the blinking curser will appear to signal that alterations can

be made.

STEP 3: Point to another cell (Navigate or click once on it).

STEP 4: Highlight/ Select the cell whose contents you need to modify. Make modifications from the

cell editing location. [Next to the formula bar]

STEP 5: Make alteration from here once the curser appears in the editing tool bar.

STEP 6: After making alterations press ‘ENTER’ to implement changes to CELL. You have just made alterations to cell data!!

14.4 Exercise 3: Formula Creation

Spreadsheets are used more often to carry out operations or implement formulae

on cell locations anywhere on the workbook. STEP 1: Highlight the CELL where you want the formulae to go or navigate to it.

STEP 2: Enter data as shown below. (Ignore the column and row references as they already appear on your worksheet.)

STEP 3: Highlight the next to John’s Test2 result. (In the above case cell 2D) Once the cell is

selected press ‘=’

on the keyboard.

NOTE 1: This signifies the beginning of a formula [ (Test1+Test2)/2 ] STEP 4: Enter the formula. Paying attention to the location of the data to be used. In our example

its:

(B2+C2)/2 STEP 5: Press ‘ENTER’ to implement the formula or signal the end of the formula input.

NOTE 2: The cell now contains the result of the formula in operation. Editing the formula can be

done in the same manner as the editing done in the Editing exercise. [From the formula bar]

Important Note: In this exercise we have chose to type in the address location of the data to be used in the formula. Another way is to simply click on the cell location whose data you want to reference]

14.5 Exercise 4: Using Predefined Formulae

In this Exercise we implement predefined formulae to obtain the result in our target

cell(s). In this example the sum of the student results is to be determined.


STEP 1: Select/ highlight location to hold result after creating an appropriate heading (Sum1)

STEP 2: Click on the fx button on the editing tool bar menu. Or go to [INSERT�FUNCTION]

STEP 3: Select formula to implement [statistical => sum]

STEP 4: Select range of data to use in formula by clicking on the minimise tab, selecting the data

whose sum

we intend to find and un‐minimise.

STEP 5: CLICK OK

[The result of that formulae execution is displayed in the originally selected cell. Similar routines are carried out to sort data and create tables.] Minimise Tab

UNIT 15: Database Systems

15.1 Introduction

A database is a collection of data sets that are stored in such a way that reduces or

eliminates duplication and redundancies in the data. Unlike files a database

attempts to store records or details of those records a minimum of once. Databases

are synonymous to computer systems as links to data and it locations are easily


handled by specialised software. The suite specialised software created to manage

the database is the database management system (DBMS), or simply a database

system (DBS). The DBMS consists of;

o A collection of interrelated and persistent data (usually referred to as the

database (DB)).

o A set of application programs used to access, update and manage that data

(which form the data management system (MS)).

o The goal of a DBMS is to provide an environment that is both convenient

and efficient to use in retrieving information from the database and storing

information into the database. Databases are usually designed to manage

large bodies of information. This involves

o Definition of structures for information storage (data modelling).

o Provision of mechanisms for the manipulation of information (file and

systems structure, query processing).

o Providing for the safety of information in the database (crash recovery and

security).

o Concurrency control if the system is shared by users.

15.2 Purpose of Database Systems

To see why database management systems are necessary, let's look at a typical file

processing system supported by a conventional operating system.

The application is a savings bank:

1. Savings account and customer records are kept in permanent system files.

2. Application programs are written to manipulate files to perform the

following tasks:

- Debit or credit an account.

- Add a new account.

- Find an account balance.

- Generate monthly statements.

3. Development of the system proceeds as follows:

- New application programs must be written as the need arises.

- New permanent files are created as required.

- But over a long period of time files may be in different formats, and

- Application programs may be in different languages. So we can see there

are problems with the straight file‐processing approach:

a. Data redundancy and inconsistency - Same information may be duplicated in several places.

- All copies may not be updated properly.

b. Difficulty in accessing data - May have to write a new application program to satisfy an unusual request.

- Could generate this data manually, but a long job...

c. Data isolation - Data in different files.

- Data in different formats.

- Difficult to write new application programs.

d. Multiple users - Want concurrency for faster response time.

- Need protection for concurrent updates.

E.g. two customers withdrawing funds from the same account at the same


- time| account has ZMK30,000 in it, and they withdraw ZMK10,000 and

ZMK15,000. The result could be ZMK20,000, ZMK15,000 or ZMK5,000 if no

protection.

e. Security problems

- � Every user of the system should be able to access only the data they are

permitted to see. E.g. payroll people only handle employee records, and cannot

see customer accounts; tellers only

- � access account data and cannot see payroll data.

- � Difficult to enforce this with application programs.

f. Integrity problems

- � Data may be required to satisfy constraints.

- � E.g. no account balance below ZMK5,000.

- � Again, difficult to enforce or to change constraints with the file‐processing

approach.

These problems and others led to the development of database management systems.

Databases provide a means of creating integrated file systems and the data is stored into

a dynamically linked, interlocked and interdependent way that augments data processing

procedures. This entails that when transactions, during data processing, enter an

integrated file in a database and a modification or alteration is made, all appropriately

linked files are updated. FIG. 27. Illustration of a database

Independence of the data and the application or user requesting the data is a very

important aspect of a database depicted above. This independence give the

applications programmers free to write code for applications whilst preserving the

form the data is stored in and where on the storage devices it is stored and leaving

those tasks to the DBMS.

15.3 Types of Databases

There are fundamentally four types of databases

1) Network Databases

2) Relational Databases

3) Hierarchical Databases

4) File inversion Databases

The de facto database standard format today is the relational database. Relational

databases use types of tables called relations. The relation term is a mathematical

relationship that expresses an entities property having links with other entities


stored in a database. This enables the formulation of maps from one location of a

database to another.

Databases may reside on a single machine (computer/ Storage device) or may be

located on several machines. When a database is split and portions of it are stored

on several machines this is referred to as a distributed database. The distributed

database is found several physically detached at times remote machines.

It is worth noting that a distributed database may not necessarily contain different

section of the data but have copies or instances of the main database at a particular

location.

Example banks and airline reservation systems use distributed databases to store

portions of the required data close or at a more accessible location to speed access

times.

Automated Teller Machine support services are a typical illustration of this practice.

15.4 Database Management Systems Composition

As discussed, for a DBMS to be useful it must be able to facilitate the addition of

files to the database, access to the files in the database, deletion of files to the

database, the manipulation of files from the data base and the construction of the

database itself. There are two main categories of routines (languages) collectively

used to achieve addition, manipulation and deletion of data in the database; the

database definition language (DDL) and the data manipulation language (DML).

15.4.1. DATA DEFINITION LANGUAGE (DDL)

These are a suite of routines and instructions that can be used to define the

database,

its tables, links and structure. The DDL is used to specify the data to be stored and

assigned characteristics. The DBMS must therefore be able to understand these

instructions and enforce them.

15.4.2. DATA MANIPULATION LANGUAGE (DML)

As the name implies, this suite of routines and instructions makes possible the

alteration of data to the database. The DML also makes possible the controlled

access of data in the data base. Imagine a database containing student results for

the BS240 module.

Assume there are 200 students taking the module and results are entered for a first

test written (TEST 1). The DML would enable the user to construct instructions to

say retrieve only the names of the students with a grade below 50%. The DML

would also enable the user to easily assign comments of the below 50% mark as

‘FAIL’.

15.4.3. DATA DICTIONARY

The DBMS makes use if descriptions of data items provided by the DDL. This is ‘data

about the data’ is the data dictionary.

15.5 Database Administration

Due to the complexity and importance of the organisational data in the database

and the complexity of the operations of the DBMS a specialised category of staff

with the relevant skills is assigned the task of managing the database. This staff

member is known as the database administrator (DBA).


Among other tasks assigned to the DBA is that of assigning access levels to portions

of the database by creating schemas. Schemas are views of data in the database. To

illustrate this assume an organisational database contains details about its

employees that include work schedules, medical details, finance details and activity

details. It would only be prudent that only persons or department that need to view

certain sections of that information be able to do so. As the information is centrally

stored if all employees had access to this information every employee would be an

‘open book’. To ensure that the accounts employees that may need to work on

finance information be able to only view this information, a schema is defined.

Other responsibilities of the DBA include: to ensure security of the database,

integrity of the database, maintain regular back ups of the database and

maintenance.

UNIT 16: The Organisation and Information Technology The digital firm: Organisation structure and IT departments. Roles of an IT department in the organisation. This section gives an introduction to the firm in the digital age context.

16.1 Introduction

Modern business practice is a complex combination of various elements that are

integrated to enhance the enterprise ability to meet its objectives. An element that

has become key to organisational success has undoubtedly been information and

communications technologies (ICT). Information and communication technology

has not only revolutionarised how business is conducted today but has also enabled

the creation of new business models.

16.2 The Digital Firm

The concept of the digital age refers to a period in time where there is a

proliferation in the use of digital electronic devices to carry out business practices

and leisure activities. This is directly related to what is referred to as the

information age. The information age refers to the period in time where the

awareness of the need to access information and the ability of individuals to access

information has dramatically risen to unprecedented levels. The symbiotic

relationship with the emergence of the appropriate digital devices becomes very

obvious. Information is not only seen as a resource but a commodity in the digital

firm. The digital device at the core of modern day data processing and information

generation is the computer.

16.2.1. WHY USE COMPUTERS

The computer is widely used today in science, engineering, business, government,

medicine, consumer goods and the arts. It is the preferred choice instrument for

the following reasons;

Volume: Ability to handle large amounts of data.

Accuracy: the need for high accuracy is satisfied by the computer and its

consistency can be relied upon.

Repetition: processing cycles that repeat themselves over and over. Once

programmed the computer happily goes on and on automaticallyperforming as

many cycles as required.


Complexity: can perform complex calculations at tremendous speeds.

Speed: high processing speeds; combined with the ability to access records

directly and from remote locations, enables computers to respond very quickly to a

given situation.

16.2.2. COMMON DATA APPLICATIONS:

Files that are related can all be stored in one physical location and accessed

together so that a decision is made in light of all the information. Contrast to a

manual system where the items of data will go through many separate independent

procedures (See

Section On Databases).

16.3 The Digital Firm & Computing Applications

How specifically does the digital firm use digital devices to meet its objectives? The

following is an overview of the applications synonymous with the digital devices

and computers in particular;

Commercial applications: clerical, administrative and business uses, in private

and public organizations, i.e. the emphasis are on data processing.

Scientific: Engineering and Research Applications: complex calculations, design,

analysis and control of physical systems and analysis of experimental data or result,

i.e. the emphasis is on scientific processing or Industrial Computing.

Routine applications: Payroll; well defined procedure sometimes involving piece

rate and bonus calculations and much of the data can be used for labour cost

control.

Order processing: notice data common to stock recording, sales ledge and

invoicing.

Office automation: involves the substantial use of computers in conjunctions

with other electronic equipment, to automate the basic secretarial and clerical

tasks of the office. Basic office automation consists of Word Processing connected

to one another and to corporate computer by means of a local network. Word

Processing: using computers to produce documents such as standard letters,

accounts, contracts, estimates etc.

Management: Company needs information on which to base decisions concerning

the current operations and future plans. It requires information to be timely and

accurate.

Examples of the use of computers in the area of management control are:

a. Stock control: the computer is able to process data quickly, making available

information on stock levels, slow moving items or trends on demand.

b. Production control: production must respond quickly to the growing

demands.

c. Labour control: an analysis of labour hours into various categories such as

idle time, sickness and absence can aid forecasting future requirement.

d. Network analysis: used for the planning and control of large complex

projects, examples building a factory, the installation of new plant and the

manufacture of an aircraft/ship.

e. Linear programming: used to find the optimum solution (i.e. maximizes

profits or minimizes costs)

f. Financial modelling: a model is constructed of the company’s finances‐its

resources, it income and its expenditure.


g. Decision support: specialised applications created to assist the manager

make decision by inputting data and its parameters and the software

generates forecasts and likely outcomes of possible alternative actions.

16.4 Integrated Appliances & New Business Models

Computing capabilities of today’s digital devices enable the formulation and

delivery of new and emerging products and services. Particularly the integrated

potential to connect to networks. Laptops PDA’s, Pocket PC’s and Smart Mobile

phone present examples of these emerging products and their delivery. Therefore

this entails that besides the other well defined properties that make computers and

computer enabled devices a part of modern data and information processing, the

emergent trends and business models necessitate the inclusion, proliferation and

use of these devices.

An example is people need to access information on the move or to transmit it

seamlessly.

Organisations exist that will provide this service for a fee or will charge other firms

to enable clients access their information.

UNIT 17: Organisation structure and IT departments Staff roles and responsibilities in a DP department. Security (physical access, programmed access, back‐‐‐‐up). Documentation in a DP department, Controls and personnel. Insight into the associated tasks and responsibilities of IT staff.

17.1 Roles of IT Departments in the organisation

The IT department in an organisation is assigned the task of overseeing all the data

processing tasks in the organisation or system. They are also responsible for

redesigning the operations in the organisation that are information intensive to

incorporate the effective use of digital devices to enhance the organisations ability

to achieve its objectives. The IT department that ensures that all the applications

mentioned in the previous section are achieved in the best possible manner. As

nearly every aspect of a modern firm depend or use information and

communication technology, it is the duty of the IT department to maintain all IT

infrastructure and techniques that supports the firms activities.

17.2 IT department Staff Specialisations

As in any department staff roles and responsibilities are specified to avoid

duplication of work and clarity in expectations of the various staff. The following

are the description, role and responsibility assigned to each member of a typical IT

department.

IT Manager The IT Manager is responsible for the overall management of the IT department.

The IT manager must plan, organise, coordinate, control and motivate the

resources of the IT department to achieve the departmental aims of the business as

a whole. The IT manager also supervises the members of the IT department and

spearheads IT development projects.

System Analyst


The Systems Analysts main roles are to execute systems development projects

initiated by the IT Manager. The Systems Analyst is responsible for managing the

system development life cycle. The Systems Analyst is meant to be the bridge

between the systems developers and the users. Thus this roles entails a complete

understanding of the business process and solutions that are IT based.

Programmer/ Software Engineer The Software Engineer works in conjunction with the Systems Analyst on system

projects. The Software Engineer converts the requirements specified by the

Systems Analyst into implementable software solutions. The Software Engineer is

responsible for writing programs if there is no existing software to be used and

testing programs during the design and implementation of a new system.

Network Administrator The modern firm, organisation or business enterprise will usually have or be

connected to a computer network. The Network Administrator is responsible for

maintaining and upgrading the computer network infrastructure in the

organisation.

Web Master Organisations that have presence on the Internet will have a Web Master to

develop and maintain the firm’s websites and mail servers.

Data Preparation Clerk The job of data preparation consists of loading data on a source documents for

processing and then storing the data to storage device after the processing is

complete. This is typical during batch processing applications such as running a

payroll.

Database Administrator See Section on Databases.

UNIT 18: Control & Security in IT Departments This section introduces the aspects of securing data on computerised systems. Physical access, programmed access, back‐‐‐‐up. Safe guarding organisational data.

18.1 Introduction

Control is defined as the ability to exercise restraining constraint on an entity.

Information security means protecting information and information systems

from unauthorized access, use, disclosure, disruption, modification, or

destruction. The terms information security, computer security and

information assurance are frequently used interchangeably. These fields are

interrelated and share the common goals of protecting the confidentiality,

integrity and availability of information; however, there are some subtle

differences between them. These differences lie primarily in the approach to

the subject, the methodologies used, and the areas of concentration.

Information security is concerned with the confidentiality, integrity and

availability of data regardless of the form the data may take: electronic, print,

or other forms.

Governments, military, financial institutions, hospitals, and private businesses

amass a great deal of confidential information about their employees,

customers, products, research, and financial status. Most of this information is


now collected, processed and stored on electronic computers and transmitted

across networks to other computers. Should confidential information about a

businesses customers or finances or new product line fall into the hands of a

competitor, such as breach of security could lead to lost business, law suits or

even bankruptcy of the business. Protecting confidential information is a

business requirement, and in many cases also an ethical and legal

requirement. For the individual, information security has a significant effect on

Privacy, which is viewed very differently in different cultures.

The field of information security has grown and evolved significantly in recent

years. As a career choice there are many ways of gaining entry into the field. It

offers many areas for specialization including Information Systems Auditing,

Business Continuity Planning and Digital Forensics Science.

18.2 The Organisation & Control

Controls: ensure the accuracy, consistency, accuracy and reliability of inputs,

outputs and data processing activities in an organization.

There are three main categories of information systems controls;

administrative, logical and physical.

Administrative controls consist of approved written policies, procedures,

standards and guidelines. Administrative controls form the framework for

running the business and managing people. They inform people on how the

business is to be run and how day to day operations are to be conducted. Laws

and regulations created by government bodies are also a type of

administrative control because they inform the business. Some industry

sectors have policies, procedures, standards and guidelines that must be

followed ‐ the Payment Card Industry (PCI) Data Security Standard required by

Visa and Master Card is such an example. Other examples of administrative

controls include the corporate security policy, password policy, hiring policies,

and disciplinary policies. Administrative controls form the basis for the

selection and implementation of logical and physical controls. Logical and

physical controls are manifestations of administrative controls. Administrative

controls are of paramount importance.

Logical controls (also called technical controls) use software and data to

monitor and control access to information and computing systems. For

example: passwords, network and host based firewalls, network intrusion

detection systems, access control lists, and data encryption are logical

controls.

An important logical control that is frequently overlooked is the principle of

least privilege.

The principle of least privilege requires that an individual, program or system

process is not granted any more access privileges than are necessary to

perform the task. A blatant example of the failure to adhere to the principle of

least privilege is logging into Windows as user Administrator to read Email and

surf the Web. Violations of this principle can also occur when an individual

collects additional access privileges over time. This happens when employees'

job duties change, or they are promoted to a new position, or they transfer to

another department. The access privileges required by their new duties are


frequently added onto their already existing access privileges which may no

longer be necessary or appropriate.

Physical controls monitor and control the environment of the work place

and computing facilities. They also monitor and control access to and from

such facilities. For example: doors, locks, heating and air conditioning, smoke

and fire alarms, fire suppression systems, cameras, barricades, fencing,

security guards, cable locks, etc. Separating the network and work place into

functional areas are also physical controls.

An important physical control that is frequently overlooked is the separation of

duties.

Separation of duties ensures that an individual can not complete a critical task

by himself.

For example: an employee who submits a request for reimbursement should

not also be able to authorize payment or print the check. An applications

programmer should not also be the server administrator or the database

administrator ‐ these roles and responsibilities must be separated from one

another

18.3 Other types of control

To determine which controls are required, designers and users of systems

must identify all of the control points and control weaknesses and perform risk

assessment. They must also perform a cost/benefit analysis of controls and

design controls that can effectively safeguard systems without making them

unusable.

The goal of control is to prevent losses to the organization arising from several

possible hazards:

1. wasteful and inefficient use of resources

2. poor management decisions

3. unintentional errors in recording or processing data

4. accidental loss or destruction of records

5. loss of assets through employees’ carelessness

6. lack of compliance of employees with management policies of

government regulations

7. embezzlement, which is the is the theft or misappropriation of

assets by employees, accompanied by the falsification of records in

order to conceal the theft

8. other illegal acts by employees, such as the taking of a bribe TABLE 7.Specific Types of Control


a

Control Types Description Software controls

Monitor the use of system software and prevent unauthorized access of software programs,

systems software and computer programs. System software is an important control area

because it performs overall control functions for the programs that directly process data and

data files

Hardware controls

Ensure that computer hardware is physically secure, and check equipment for malfunction.

Computer equipment should be specially protected against fires and extremes of temperature

and humidity. Organizations that are critically dependent on their computers also must take

provisions for backup or continued operation to maintain constant service.

Computer operations controls

Oversee the work of the computer department to ensure that programmed procedures are

consistently and correctly applied to the storage and processing of data. They include controls

over the setup of computer processing jobs and computer operations, and backup and recovery

procedures for processing that ends abnormally.

Implementation controls


Audit the systems development process at various points to ensure that the process is properly

controlled and managed

Data security controls

Ensure that valuable business data files on either disk or tape are not subject to unauthorized

access, change, or destruction while they are in use or in storage.

Administrative controls

Formalized standards, rules procedures and control disciplines to ensure that the organization’s

general and application controls are properly executed and enforced.

Management controls

The process by which managers ensure that resources are obtained and used effectively and

efficiently in the accomplishment of the organization’s objectives

18.4 Application Controls Application controls: specific controls unique to each computerized application, such as payroll

or order processing. They consists all controls applied from the business functional area of a

particular system and from programmed procedures. Classifications of application controls are:

i. Input controls: the procedures to check data for accuracy and completeness when they

enter the system.

ii. Processing controls: the routines for establishing that data are complete and

accurate during updating.

iii. Output controls: measures that ensure that the results of computer processing are

accurate, complete and properly distributed

These controls and mechanisms put together form the basis of ensuring that organisational data is safe from corruption and exposure to error generation.

18.5 Security Risks and Threats to Information Systems

Hacking of computerised information systems is defined as the unauthorised

access, theft and alteration of data. Hackers pose some of the more serious threats

to corporate data. Some of the more common threats that hackers pose to

information systems include:

o Carrying out denial‐of‐service attacks that stop access to authorized users of

a system.

o Gaining access to sensitive data such as price lists, catalogues and valuable

intellectual property, and altering, destroying or copying it.

o Gaining access to valuable information about your business or your

customers, with a view to perpetrating fraud.

o Using viruses to corrupt your business data and or even execute data theft

and alterations

UNIT 19: Classification of Files Computer files and the structure of data in computers. Data validation methods.

19.1 Introduction

The basic building block of computer data is the character. Single characters rarely

represent useful information on their own but several are grouped together as a

single logical piece of information to form a field such as a customer name, an order

number or a description of a product. Even fields are rarely useful on their own and

most data processing problems require that a number of related fields be grouped


and processed together as a record ( a single record might have the following fields:

customer name, customer number, order number, salesman, product code,

quantity ordered, sales value). Therefore the most prevalent way of data storage

involves the collection of records called files.

- An organized collection of records is called a file.

- A set of integrated files in a data processing is called the database.

- All the records in a file are usually of the same type; i.e. they contain similar

fields.

- Each of the records in a file is discrete and is labelled/identified by a key

field (primary key)

- A field might be composed of subfields e.g. subfields of an address field:

street name, town, country and postal code.

19.2 File Classifications

Files can be classified in one of a number of ways. These classifications enable

attributes to be associated to each of the file types. This may be for easy

identification or application program association. The following are the main

classifications associated with file systems:

o Status – permanent or temporary;

o Contents – data or program, binary or alphanumeric,

o Main file or overflow‐file;

o Role – for input, or output or both;

o Structure and organization of contents;

o Size;

o Frequency of access;

o Volatility (frequency of modification);

o Speed of access required ‐ real‐time use or batch;

o Security and protection required.

19.3 Master Files and Transaction files

The master file is an example of a permanent file although details are always being

continually updated. Transactions, i.e. additions to and deletions from inventory are

used to update a master file. The transaction file is temporary file and once the

updating has been carried out, is of less value and can eventually be deleted.

Updating master files This updating required may be insertion of new records in the file, deletion of

specified existing records or perhaps changing the values of one or more fields in

existing records.

A Reference file is a file with a reasonable amount of permanency. Examples of

data used for reference purposes are price lists, tables of rates of pay, names and

addresses.

19.4 File Organisation

We discuss four basic types of file organization:

Serial files: Records are stored in adjacent locations as they occur; typically a series of

transactions when input and stored on magnetic tape.

o To locate any particular record in a file of n records involves examination of

an average of n/2 record before the required record is found and all records


must be inspected before we can deduce that the required record is not in

the file.

o The process of updating a master file stored serially can be very inefficient.

Sequential files: o Records are stored in position relative to other records in order of some

chosen key field.

o A record in the file is located simply by starting at the beginning of the file

and comparing the value of the key field of each successive record with the

desired key until a match is found

o Ideal for batch processing where transactions can be accumulated sorted

and then processed efficiently against the master file.

o The sequential file can be stored on the least expensive storage medium

namely magnetic tape.

Random files o Allows any record in the file to be retrieved by a single (direct) access to the

file; other records do not have to be examined as in sequential files.

o Batch processing of sequential files is not always appropriate for example in

the case of an airline reservation you will not be prepared to wait until

shortly before the flight for confirmation of your booking.

o One disadvantage is a random file organization is that it cannot be accessed

in any other way as the records are held in any particular sequence and are

not necessarily in continuous locations. Indexed sequential

o is a comprise between sequential organization and random organization.

o records are stored in order of key values so that sequential processing is

possible but an ordered index is also maintained to facilitate efficient access

by key value to selected individual records

UNIT 20: Introduction to Systems Concepts This section introduces the concept of information systems. Their composition, types and use in the organisation.

20.1 Definition of Systems.

The integral function of an information system is the production of information

from data.

It attempts to process either data or information through a series of processes.

Data is a basic fact or observation quantified into simple units. Data are facts that

are entered, stored and processed by an information system. Information is

obtained by assembling items of data into a meaningful form. This may be achieved

through processes such as collection, groupings, analysis, calculation or

manipulation.

A System is simply two or more interrelated units that interact for the purpose of

achieving a common objective. An Information System is an organised collection of

hardware, software, supplies, policies, procedures and people, which store, process

and provide access to information. Information systems also provide a supportive

and collaborative role into an organisations business practice.


The inter‐operability of the system necessitated the presence of good relationships

between the components of the system. Thus any action in a subsystem or

component of the system should take into consideration its overall effect in the

entire system. [Its effect to the whole system within the collective objectives in

focus]. This is referred to as the systems concept. Alternative actions must be

evaluated from a standpoint of the entire system and not mere parts of it.

Goals conflict Refers to a scenario when goals/actions of a systems component conflict that of

another component of the system.

Goal congruence This term refers a scenario when individual component objectives and actions

contribute to the global systems objectives. The presence of sub‐systems or

components with different sub‐goals which meet the overall objectives of the

entire system (e.g. judicial system and health system of a country).

Integration This refers to the combining of subsystems for increased efficiency or effectiveness.

Like any other systems, an information system is basically an organized means of

undertaking information processing through stages by one or more unit

component.

20.2 Types Information Systems

An information system may be manual, information technology intensive or a

mixture.

Information systems are also classified in relation to what tasks they are set up to

carry out.

Characteristics of Manual Systems: o Slow

o Error prone (humans are prone to errors when in the presence of

incompetence and fatigue

o Use higher IQ (The people operating in these systems exert a lot of mental

energy)

o Flexible (easily incorporate other differing aspects or even new ones)

o Adaptable (easily transferable or implementable)

Characteristics of Automated Systems (computer based) o Fast

o Deals with many processes better

o Costly design and development

o Not easily adaptable

Whether manual or automated information systems can be classified

further based on two paradigms; business function they support and type of

activity they carry out.

20.3 Components of an information system

Below are the main components of the information systems model. These form the

essential building blocks of any information system.

o Goals and objectives

o Input (Data gathered and entered/transaction data)

o Output (Feedback) Reports, Financial Statement, Budgets

o Data storage

o Processor


o Instructions and procedures (Software – Procedure manuals)

o Users (People who interact with the system and utilize the information)

o Controls and security measures

The diagram below depicts the underlying interactions of the components of the

Users Goals and objectives

Management Information systems A Management Information System (MIS) is a collection of all the systems in an

organization collectively processing and providing information to aid decision

makers optimize the organization’s resources to better achieve the

organization’s goals. Thus all information needed for planning, control, directing

and decision‐making is produced from management information systems. With

the complexity of modern business operations, systems of processing

information are required that facilitate or enable the effective use of

information to manage the operations of the organisation.

UNIT 21: Systems Analysis & Design

21.1 Introduction to systems Development

Gaining competitive advantage and improving information delivery will edge an

organization to restructure its activities. The information system has to be

developed to suit the business scenario and objectives. It needs to be carefully

planned and activities well thought of. Most organizations will rarely develop whole

systems from scratch.

Therefore, system will usually be in place, but may need changing, upgrading,

improving to meet the objectives (information processing) of the business. The

business may need to operate in a more efficient or reliable way or simply to

provide a better service.

Reasons for the need to adopt new strategies or system may be:

o Changes in user or business needs

o Technological changes

o Improved business processes

o Productivity gains

o Growth

o Quality of serviced delivery improvement


Methods of information systems development were formulated to be a guide and

standard to information systems developers. These techniques are intended to

assist developers effectively develop information systems [thought process].

A five‐step process known as the systems development life cycle (SDLC) is given as

the blueprint of information systems development. This approach is stipulated in

the set of development methodologies known as the Structured Systems Analysis &

Design Methodology (SSADM)

It is comprised of the following stages:

o Systems analysis

o Conceptual design

o Physical design

o Implementation and conversion

o Operation and maintenance

21.2 Systems Development Life Cycle (SDLC)

The SDLC is an approach in the SSADM that is intended to provide a means of

ensuring that the development of a system is complete and verifiable. It also

provides a means of counter checking segmented steps for completeness and

errors if any. However this approach has been criticised because it is only well

suited for development projects that are intended to build systems from scratch.

Alternative approaches are the Rapid Application design (RAD) and the Joint

Application Design (JAD).

21.3 Systems Analysis

The systems analysis stage is the analysis of the problem that the organisation will

try to solve with an information system. It consists of defining the problem,

identifying its causes, specifying the solution and identifying the requirements that

must be met by a system solution. The systems analysis includes the following

stages or activities:

o Initial investigation

o Systems survey

o Feasibility study

o Systems requirements specification

21.3.1. INITIAL INVESTIGATION

At this stage the problem scenario is investigated and problems established. A

clear insight into the existence of a problem is to be gained and whether an

information systems approach or development is a probable solution. During the

initial investigation the following activities are carried out:

o Gain clear picture/understanding of problem

o Project proposal is made

o Viability expected costs/pay off

o Recommend whether project should proceed

o Screening of the project

21.3.2. SYSTEMS SURVEY

The initial investigation is a quick overview of the problem scenario and likely

solution. The systems survey leads to a more detailed understanding of the


nature of the problem and what can be done in specific terms to solve it. The

systems survey will incorporate the following aspects:

o Detailed initial investigation

o Areas of weakness facility in current system highlighted

o Understand how a current system works (hardware, software, personal)

o Determine extent of and nature of system changes

o Verify user needs

21.3.3. FEASIBILITY STUDY

This is a follow up from the systems survey. It is a detailed investigation of the

implication of the proposed solution. It is an assessment of the

economic/hardware/personal implications of the proposed system. The feasibility

study will focus on the these issues:

o Will the proposed system deliver the information needs?

o Technical feasibility‐ is the technology up to date?

o Operational feasibility ‐ can it be designed and implemented by the

developers?

o Legal feasibility ‐ contractual obligations

o Scheduling feasibility ‐ development time.

o Economics feasibility ‐ is effort worthwhile time / money

21.3.4. INFORMATION NEEDS IDENTIFICATION AND SYSTEM REQUIREMENTS

This is the stage at which the analysts stipulate exactly what is to be achieved by

the system to be developed. It is a careful evaluation of what is expected of the

new system by the users of the system and documenting it. The analysts will also

established the specific information needs of the organisation and translate them

to systems requirements.

How do analysts come up with systems requirements?

1. Ask users what they want achieved

2. Observe and analyse existing systems and their operation

3. Prototyping

21.4 Systems Design

At this stage the analysts conceptualise the solution based on the identified system

requirements. There are two main design phases the logical/conceptual design and

the physical design. The physical design is a step closer to implementation and

therefore takes into consideration the available resources, equipment and

infrastructure, where as the logical design focuses on the logic behind the solution

and documenting it.

21.5 Implementation of Design.

This is the execution of the blueprint stipulated at the physical design phase. A

working solution is at this point executed. Testing follows the implementation

phase and if the system is successfully implemented, maintenance carried out on

the operational system.


UNIT 22: Introduction to E‐‐‐‐Commerce This section introduces the eCommerce paradigm and discusses the fundamental aspects concerning the use of connected information systems to facilitate business transactions.

22.1 Introduction

With the rapidly advancing technologies that are occurring in modern business,

organizations are required to be ready, and able to adapt within their ever‐changing

environment. The Internet and its use have grown significantly over the past

decade and is now commonly used in all sectors of societies, in all corners of the

globe. The Internet has quickly become one of the most valuable assets in modern

technology, and as such, is developing as an integral part of modern commerce. As

with past technologies, the Internet will have future technological advances

develop from its own growth.

The Internet has lead to the birth and evolution of electronic business (E‐business)

and electronic commerce (E‐commerce). E‐commerce has now become a key

component of many organizations in the daily running of their business. Simply

defined, electronic commerce is a system of online shopping and information

retrieval accessed through networks of personal computers.

22.2 E‐‐‐‐Business

Electronic business is any information system or application that empowers

business processes. Today this is mostly done with web technologies. E‐business

applications can be divided into three categories: 1) Internal business systems

Internal business systems are the systems that deal with operations within an

organisation and include customer relationship management, enterprise resource

planning, employee information portals, knowledge management, workflow

management, document management systems, human resource management,

process control and internal transaction processing.

2) Enterprise communication and collaboration

Communication in an organisation and the provision of information are vital

aspects of any corporation’s success. In E‐business, these are facilitated by e‐mail,

voice mail, discussion forums, chat systems, data conferencing and collaborative

work systems. 3) Electronic Commerce - Business-to-business electronic commerce, business-to-consumer electronic commerce or consumer-to-consumer electronic commerce

E‐commerce is the conduct of business communications and management through

electronic methods, such as electronic funds transfer, supply chain management, E‐

marketing, online transaction processing.

E-business applications can be available to different kind of users: o All users of the internet o Only the people connected to an intranet o A specified targeted group of users of an extranet (like customers, partners

etc.) E-business has transformed the way we interact with our customers, partners, and employees. Companies are increasingly using information and communication technologies to link their business processes: internally, with their suppliers, customers and for cooperation with business partners.


E-business matters because it … o is a driver of product and process innovation. o has implications for productivity and competitiveness. o has impacts on supply chain configurations.

22.3 E‐‐‐‐Commerce

Electronic commerce or E‐commerce consists of the buying, selling, marketing, and

servicing of products or services over computer networks. The information

technology industry might see it as an electronic business application aimed at

commercial transactions.

22.4 Types of E‐‐‐‐Commerce

Classifications of E‐commerce are by the nature of the transaction or the

relationship among participants. The following are some of the common

categorizations of E‐commerce.

o Business-to-business (B2B): This is an E-commerce model in which all of the participants are businesses or other organisations.

o Business-to-consumer (B2C). In this model, businesses sell to individual shoppers.

o Consumer-to-business (C2B). Here, individuals use the Internet to sell products or services to organisations or individuals seek sellers to bid on products or services they need.

o Consumer-to-consumer (C2C). This model allows consumers to sell directly to other consumers.

o Business-to-business-consumer (B2B2C). A business provides some product or service to a client business that maintains its own customers.

o Mobile commerce (M-commerce). These are E-commerce transactions and activities that are conducted in a wireless environment. Location-based commerce (lcommerce) is a branch of M-commerce transactions that targets individuals in specific locations, at specific times.

22.5 Growth of E‐‐‐‐Commerce

E-commerce is not a new phenomenon by any means. The applications of E-commerce began in the early 1970s in the financial sector. Some of the applications involved Electronic Funds Transfer (EFT) which could be routed electronically between financial institutions via telecommunication networks. This fast, paperless and secure form of electronic communication is now the only practical way of handling the massive volumes of transactions generated daily. Even automated teller machines (ATMs) are a form of Ecommerce; every time the customer uses the ATM it involves a transaction made over a computer network – an extension of EFT network. However, the extent of the applications was limited to large corporations, financial institutions and a few other daring businesses. In the 1980s, the use of E-Commerce expanded considerably and the prime vehicle for this was Electronic Data Interchange (EDI) – a technology used to electronically transfer routine documents, which expanded electronic transfers from financial transactions to other types of transaction processing. The Internet began as an experiment by the United States government in 1969 and its initial users were a largely technical audience of government agencies and academic researchers. When the Internet commercialised and users began flocking to participate in the World Wide Web (WWW) in the early 1990s, the term E-commerce was coined leading to E-commerce applications expanding rapidly. Since 1995, Internet users have witnessed the development of many innovative applications, ranging from on-line direct sales to e-learning experiences. Almost


every medium- and large- sized organisation in the world now has a web site. In 1999, the emphasis of E-commerce shifted from B2C to B2B, and in 2001 from B2B to B2E (Business to Employees), c-commerce, e-government, e-learning and m-commerce. This revolution has gained considerable attention particularly as new and agile start ups with fresh ideas and business models begin to capture large revenues. This has started a cycle of interest, demand and expectation. Given the nature of technology and the Internet, E-commerce will undoubtedly continue to shift and change. Lately, we are seeing more and more Ecommerce successes such as the capitalisation of very new E-commerce – oriented companies such as the Amazon.Com soar to unprecedented levels, eToys.Com being the first ever to the on-line toy retail market offering a clean well – executed and easy to use website where customers can view product and purchase on-line, eBay, AOL and Checkpoint. Growth of E-commerce is phenomenal and new estimates frequently outstrip the old. Today’s predictions of about the future size of E-commerce provided by respected analysis such as Forrester Emarkeher.Com and AMR Research vary. The number of Internet users worldwide is predicted to reach 750 million by 2008. Experts predict that as many as 50% of all Internet users will shop online by that time. E-commerce growth will come not only from B2C but, also from B2B and from C-Commerce. Overall, the growth of the field will continue into the foreseeable future.

UNIT 23: Benefits and limitations of E‐‐‐‐Commerce Few innovations in human history encompass as many benefits as E-commerce does. The global nature of the technology, the opportunity to reach hundreds of millions of people, the interactive nature of E-commerce, the variety of possibilities for its use, and resourcefulness and rapid growth of its supporting infrastructures, especially the Web, result in many potential benefits to organisations, individuals and society These benefits are just starting to materialise, but they will increase significantly as E-commerce expands.

23.1 Benefits to Organisations 1. Global reach. E-commerce expands the market place to national and

international markets. With minimal capital outlay, a company can easily and quickly locate the best suppliers, more customers, and the most suitable business partners worldwide, expanding the base of customers and suppliers enables organisations to buy cheaper and sell more.

2. Cost reduction. E-commerce decreases the cost of creating, processing, distributing, storing, and retrieving paper-based information. High printing and mailing costs are lowered or eliminated.

3. Supply chain improvements. Supply chain inefficiencies, such as excessive inventories and delivery delays, can be minimized with E-commerce, e.g. by building autos to order instead of for dealers’ showrooms, the automotive industry is expecting to save billions of dollars annually just from inventory reduction.

4. Extended hours. The business is always open on the Web, with no overtime or other extra costs.

5. Customisation. Pull-type production (build-to-order) allows for inexpensive customisation of products and services and provides a competitive advantage for companies who implement this strategy.

6. New business models. E-commerce allows for many innovative business models that provide strategic advantages and/or increase profits.


7. Vendors’ specialisation. E-commerce allows for a high degree of specialisation that is not economically feasible in the physical world. For example, a store that sells only dog toys (Dogtoys.com) can operate in cyberspace, but in the physical world such a store would not have enough customers.

8. Rapid time-to-market. E-commerce reduces the time between the inception of an idea and its commercialisation (due to improved communication and collaboration).

9. Lower communication costs. E-commerce lowers telecommunication costs – the Internet is much cheaper than Value Added networks (VANs).

10. Efficient procurement. E-commerce enables efficient e-procurement that can reduce administrative costs by 80% or more, reducing purchasing prices by 5 to 15%, and reducing cycle time by more than 50%.

11. Improved customer relations. E-commerce enables companies to interact more closely with customers, even if through intermediaries. This allows personalisation of communication, products, and services, which promotes better customer relationship management (CRM) and increases customer loyalty.

12. Up-to-date company material. Any material on the Web, such as prices in catalog, can be correct up to the minute. All company information can always be current.

13. No city business permits and fees. Online companies do not need any licenses to operate nor do they pay license fees.

14. Other benefits. These include improved corporate image, improved customer service, new business partners, increased productivity, reduced paper and paperwork, increased access to information, reduced transportation costs, and increased operation and trading flexibility.

23.2 Benefits to consumers 1. Ubiquity. E-commerce allows consumers to shop or perform other

transactions year round, from almost any location. 2. More products and services. E-commerce provides consumers with more

choices; they can select from many vendors and from more products. 3. Cheaper products and services. E-commerce frequently provides

consumers with less expensive products and services by allowing them to shop in many places and conduct quick comparisons.

4. Instant delivery. In the case of digitized products, E-commerce allows for quick delivery.

5. Information availability. Consumers can locate relevant and detailed product information in seconds, rather than days or weeks. Also, multimedia support is cheaper and better.

6. Participation in auctions. E-commerce makes it possible for consumers to participate in virtual auctions. These allow sellers to sell things quickly and buyers to locate collectors’ items and bargains.

7. Electronic communities. E-commerce allows customers to interact with other customers in electronic communities and exchange ideas as well as compare experiences.

8. “Get it your way.” E-commerce facilitates customization and personalisation of products and services.

9. No sales tax. In many countries, online business is exempt from sales tax.

23.3 Benefits to society 1. Telecommunicating. More individuals work at home and do less travelling

for work or shopping, resulting in less traffic on the roads and reduced air pollution.


2. Higher standards of living. Some merchandise can be sold at lower prices, allowing less affluent people to buy more and increase their standard of living.

3. Hope for the poor. People in Third World countries and rural areas are now able to enjoy products and services that were unavailable in the past. These include opportunities to learn skilled professions or earn a college degree.

4. Availability of public services. Public services such as health care, education, and distribution of government social services, can be done at a reduced cost and/or improved quality. For example, E-commerce provides rural doctors and nurses access to information and technologies with which they can better treat their patients.

23.4 Limitations of E‐‐‐‐commerce 1. Failure to understand customers, why they buy and how they buy. Even a

product with a sound value proposition can fail if producers and retailers do not understand customer habits, expectations, and motivations. E-commerce could potentially mitigate this potential problem with proactive and focused marketing research, just as traditional retailers may do.

2. Inability to predict environmental reaction. What will competitors do? Will they introduce competitive brands or competitive web sites? Will they supplement their service offerings? Will they try to sabotage a competitor's site? Will price wars break out? What will the government do? Research into competitors, industries and markets may mitigate some consequences here, just as in non-electronic commerce.

3. Over-estimation of resource competence. Can staff, hardware, software, and processes handle the proposed strategy?

4. Failure to co-ordinate. If existing reporting and control relationships do not suffice, one can move towards a flat, accountable, and flexible organizational structure, which may or may not aid co-ordination.

5. Failure to obtain senior management commitment. This often results in a failure to gain sufficient corporate resources to accomplish a task. It may help to get top management involved right from the start.

6. E-commerce involves an unusual mix of people. Security people, Web technology people, designers, marketing people – and can thus be very difficult to manage, and needs supervision by specialists, which can be very expensive.

7. There are difficulties in integrating the Internet and E-commerce software with existing applications and databases.

8. The international availability of a website means that the laws of all countries that transactions may be conducted from have to be considered. The legal issues surrounding the E-commerce are complex and still developing.

9. Security and privacy concerns deter customers from buying. Internet merchants need to address issues such as fear of invasion of privacy and abuse of customer information because they stop people even considering the Internet as a shopping medium.

10. People do not yet sufficiently trust paperless, faceless transactions. The parties involved in E-commerce need to have confidence that n communication sent get to its target destination unchanged and without being read by anyone else.

11. Lack of trust in E-commerce and in unknown sellers hinders buying. In most cultures consumers grant their trust to business parties that have a close physical presence buildings, facilities and people to talk to. On the Internet these familiar elements are simply not there. The seller’s reputation, the size of his business, and the level of customization in


product and service also engender trust. Internet merchant need to elicit consumer trust when the level of perceived risk in a transaction is high.

23.5 Future of E‐‐‐‐commerce

The future sees E‐commerce rising to become an increasingly important method of

reaching customers, providing services, and improving operations of business.

Non‐technological as well as technological factors indicate a general optimism

about the future of E‐commerce The non-technological factors include: o The rapid increase in the number of Internet users o The increase in the number of products and services sold online o Increased security and trust of electronic transactions o Efficient handling of information o Increasingly innovative organizations o Globalization of E-commerce

Trends in E-commerce technologies generally point towards significant cost reductions coupled with improvements in capabilities, ease of use, increased availability of software, ease of site development and improved security and accessibility. Specific technological aspects that indicate the furtherance of E-commerce are: o Availability of E-commerce software and services o Development of peer-to-peer technology o Development of Web services o Interactive television

EXERCISE 4 1. In not more than 600 words, discuss the challenges faced by software publishers

with regards to copyright infringement.

2. In not more than 600 words discuss the constraints and prohibitions faced by

members of society who seek reliable off‐the‐shelf software giving possible

alternatives.

3. Give a detailed description of the roles of a database administrator.

4. Does the modern organisation require information technology to survive? Give at

least six arguments that support each of the possible alternative answers to this

question.

5. How does the allocation of uniquely identifiable roles impact the controls laid out

in an organisation attempting to safeguard data corruption.

6. Distinguish clearly between three systems design methodologies.

7. The modernistic view of opportunities presented by the internet through the

application of e‐commerce technologies presents valid challenges to

organisations that are slow to adopt the implementation of new innovations. Can

Zambian organisations thrive given this paradigm in the global economy? Discuss

in not less than 1000 words.


ASSIGNMENTS

ASSIGNMENT 1

Experts predict that notebook computers will have 10 times the power of a current personal

computer, with a touch sensitive colour screen that one can write on or draw with a stylus, or

type on when a program displays a keyboard. Each will have a small, compact, rewritable,

removable CD‐ROM that can store the equivalent of a set of encyclopaedias. In addition, the

computers will have voice‐recognition capabilities, include the ability to record sound and

give voice response to questions. The computers will be able to carry on a dialogue by voice,

graphics, typed words and displayed video graphics. Thus, affordable computers will be about

the size of a thick pad of letter paper and just as portable and convenient, but with the

intelligence of a computer and the multimedia capabilities of a television set.

Develop an analysis of the impacts (at least such developments would have on one of these

areas: university education, corporate sales and marketing, manufacturing, or management

consulting. Explain why you think the impact will or will not occur. If possible, use electronic

presentation software to present your findings.

Due date: 28/AUGUST/2009


ASSIGNMENT 2 Analyzing a Business System

Find a description in a computer or business magazine or on the Internet of an information

system used by an organization. Look for information about the company on the Web or

other sources to gain further insight into the company and prepare a brief description of the

business.

Describe the system you have selected in terms of its inputs, processes and output and in

terms of its organization, management, and technology features and importance of the

system to the company.

Due date: 14/SEPT/2009

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