DESIGN AND IMPLEMENTATION OF EXPERT SYSTEM FOR LOCAL AREA NETWORK TROUBLESHOOTING

ABSTRACT

This work is designed to provide assistance in engaging and overcoming challenges involved in troubleshooting and maintenance of local area networks. It is presented in such simplified, easytouse way, that even users who are not experts in the field of networking, computer and/or communication engineering can relate with, and can apply its expertise to obtain various network solutions. Whenever there is a need to monitor a computer network and/or to troubleshoot in the event of a fault, the software package which is the end product of this project work can be installed or run on any of the computers within the network. With the assistance offered by the software, and with the wealth of a thorough knowledgebase captured within the software package, the needed solution for rectification of the network will be reproduced for the operator to apply. Hence, it is termed Expert System for Local Area Network Troubleshooting.

TABLE OF CONTENTS

University Logo Page .. .. .. .. .. .. .. ii

Title Page .. .. .. .. .. .. .. .. .. iii

Certification page .. .. .. .. .. .. .. .. iv

Approval page .. .. .. .. .. .. .. .. v

Acknowledgement .. .. .. .. .. .. .. .. vi

Dedication .. .. .. .. .. .. .. .. .. vii

Abstract .. .. .. .. .. .. .. .. .. viii

Table of contents .. .. .. .. .. .. .. .. ix

List of Figures .. .. .. .. .. .. .. .. xiii

List of Tables .. .. .. .. .. .. .. .. xiv

Abbreviations .. .. .. .. .. .. .. .. xv

CHAPTER ONE: INTRODUCTION .. .. .. .. 1

1.1 Background .. .. .. .. .. .. .. .. 1

1.2 Aims and Objectives .. .. .. .. .. .. 3

1.3 The Need for the Project work .. .. .. .. .. 4

1.4 Scope of the work .. .. .. .. .. .. .. 5

1.5 Project Report Organisation .. .. .. .. .. 7

CHAPTER TWO: LITERATURE REVIEW.. .. .. 9

2.1 Review of other related works .. .. .. .. .. 9

2.2 Expert Systems .. .. .. .. .. .. .. 16

2.2.1 Knowledge Representation .. .. .. .. .. 20

2.2.2 Reasoning Mechanism .. .. .. .. .. .. 22

2.2.3 Expert System Shell .. .. .. .. .. .. 23

2.2.4 Advantages of using Expert Systems .. .. .. .. 19

2.3 Computer Networks .. .. .. .. .. .. 24

2.3.1 Different types of networks .. .. .. .. .. 26

2.3.2 Categories of Networks .. .. .. .. .. .. 27

2.3.3 Network topologies .. .. .. .. .. .. 28

2.3.4 Network troubleshooting .. .. .. .. .. .. 33

2.4 Overview of different LAN components .. .. .. 35

2.4.1 Switches, Hubs and Bridges .. .. .. .. .. 35

2.4.2 Routers and Gateways .. .. .. .. .. .. 36

2.4.3 Modems .. .. .. .. .. .. .. .. 38

2.5 Wireless LAN and Bluetooth Technology .. .. .. 39

CHAPTER THREE: METHODOLOGY, SYSTEM DESIGN

AND IMPLEMENTATION .. .. 41

3.1 Research Methodology .. .. .. .. .. .. 41

3.1.1 Knowledge Acquisition and Analysis .. .. .. .. 42

3.1.2 Modeling and implementation .. .. .. .. .. 43

3.1.3 Testing and Validation .. .. .. .. .. .. 44

3.1.4 Documentation .. .. .. .. .. .. .. 44

3.1.5 Knowledge Acquisition process .. .. .. .. .. 45

3.2 System Design .. .. .. .. .. .. .. 46

3.3 System Modeling .. .. .. .. .. .. .. 52

3.3.1 Modeling the Internet Browsing problem .. .. .. 53

3.3.2 The Diagnosis Layer.. .. .. .. .. .. .. 55

3.3.3 Model for No LAN Connection .. .. .. .. .. 61

3.3.4 Model for File and Printer Connection problems .. .. 66

3.3.5 Model for Bluetooth Device Connection problems .. .. 71

CHAPTER FOUR: SYSTEM INSTALLATION AND TESTING 77

4.1 To Install/Uninstall QT Expert System .. .. .. 77

4.2 To Launch or Begin the program .. .. .. .. 79

4.3 Running the QT software .. .. .. .. .. .. 80

4.4 Testing and Validation .. .. .. .. .. .. 86

CHAPTER FIVE:CONCLUSION AND RECOMMENDATIONS 88

5.1 Conclusion .. .. .. .. .. .. .. .. 88

5.2 Recommendations .. .. .. .. .. .. .. 89

REFERENCES .. .. .. .. .. .. .. .. 91

APPENDICES

Appendix A: Questionnaire for Knowledge Acquisition .. 95

Appendix B: Visual Basic program codes for the Expert System

development .. .. .. .. .. 98

LIST OF FIGURES

Fig. 1.1 Block diagram showing the various project

development stages.. .. .. .. .. 6

Fig. 2.1 Major parts of an Expert System.. .. .. 19

Fig. 3.1 QuickHelp Troubleshooter Expert System

Architecture .. .. .. .. .. .. 48

Fig. 3.2 Inference Tree showing possible faults for Internet

Browsing problems in a LAN connection.. .. 56

Fig. 3.3 Inference Tree showing possible faults for No LAN

Connection problems .. .. .. .. 63

Fig. 3.4 Inference Tree showing possible faults for File and

Printer connection problems .. .. .. 68

Fig. 3.5 Inference Tree showing possible faults for Bluetooth

Device connection problems .. .. .. 73

Fig. 4.1 The Welcome window for the Troubleshooter.. 82

Fig. 4.2 Inference page .. .. .. .. .. 84

Fig. 4.3 Typical Explanation/Recommendation page .. 85

LIST OF TABLES

3.1 Table showing Variables and their States for Internet

Browsing problems in a LAN connection .. .. 53

3.2 Program modules for Internet Browsing problems

in a LAN .. .. .. .. .. .. .. 58

3.3 Table showing Variables and their States for No LAN

Connection problems in a LAN .. .. .. .. 61

3.4 Program Modules for No LAN connection .. .. 64

3.5 Table showing Variables and their States for File

and Printer connection problems in a LAN .. .. 67

3.6 Program Modules for File and Printer connection

Problems .. .. .. .. .. .. .. 69

3.7 Table showing Variables and their States for Bluetooth

Device connection problems in a LAN .. .. 72

3.8 Program Modules for Bluetooth Device connection

Problems .. .. .. .. .. .. .. 74

ABBREVIATIONS

LAN Local Area Network

AI Artificial Intelligence

WLAN Wireless Local Area Network

OS Operating System

WAN Wide Area Network

MAN Metropolitan Area Network