1. information systems defined small enterprise characteristics Information needs of the small enterprise the systems development life cycle computer information system components the role of the analyst methodologies, tools, and techniques the enhanced SDLC portfolio project Systems Analysis and Design for the Small Enterprise section I Introduction

2. Systems definition a set of entities, real or abstract, comprising a whole where each component interacts with or is related to at least one other component. Any object which has no relation with any other element of the system is not part of that system but rather of the system environment. A subsystem then is a set of elements, which is a system itself, and a part of the whole system. In other words...

3. Systems definition A system is composed of regularly interacting or interrelating groups of activities/parts which, when taken together, form a new whole. In most cases this whole has properties which cannot be found in the constituent elements....

4. Systems definition example

5. Car as a System Car –Propulsion (engine) Fuel Electrical –Control Braking Steering Acceleration –Signal –Safety Starting Seatbelts Air bags –Comfort Temperature Entertainment –Radio –TV / Video –Monitoring Speedometer Odometer Temperature Oil

6. The concept of a system 6

7. How do the “rules” change 7

8. 8

9. Systems definition example System: An interrelated set of components, with an identifiable boundary, working together for some purpose

10. General System Depiction Environment: Everything external to a system that interacts with the system.

11. General System Depiction Boundary: The line that marks the inside and outside of a system and that sets off the system from its environment.

12. General System Depiction Components: An irreducible part or aggregation of parts that make up a system, also called a subsystem..

13. General System Depiction Interrelationship: Dependence of one subsystem on one or more subsystems.

14. General System Depiction Input: Whatever a system takes from its environment in order to fulfill its purpose.

15. General System Depiction Output: Whatever a system returns to its environment in order to fulfill its purpose.

16. General System Depiction Interfaces: Point of contact where a system meets its environment or where subsystems meet each other.

17. Information Systems Defined An information system is a well-coordinated collection of resources that gather and transform data into information products and services that help the enterprise perform its designed functions An information system hierarchy associates different classifications of information systems with different audiences 17

18. 18 Information System Hierarchy

19. Information Systems Defined 19 Three significant trends influence the evolution of information systems and provide opportunities for the entrepreneurial systems analyst: The emergence of small enterprise computing The Internet as a dominating technology The maturation of application software

20. Small Enterprise Characteristics 20 The following small enterprise characteristics influence the analyst’s work: Owner participation Economic constraints Competitive pressures

21. Information Needs of the Small Enterprise 21 The following are common information needs of any enterprise: Production and inventory Personnel Financial reporting Marketing, sales, and service Customer relations

22. Computing Terminology 22 TECHNOTE 1-1 Several software products are integral to the analyst’s work: Off-the shelf application software Software suites Computer assisted systems engineering (CASE) Object-oriented application software

23. The Systems Development Life Cycle 23 The systems development life cycle (SDLC) consists of five major phases: Analysis Design Development Implementation Maintenance

24. The Circular SDLC 24

25. The Recurring SDLC 25

26. Information System Components 26 There are six major information system components: People Procedures Software Hardware Networks Data Reference Figure 1-7: Information System Components

27. Software Classifications 27 TECHNOTE 1-2 System Software Operating systems Firmware Utility Application Software Horizontal Vertical Turnkey Customizable Software Third-generation programming languages Fourth-generation programming language (4GL) Object-oriented programming language 4GL products

28. The Role of the Analyst 28 An agent of change A problem-solving strategist A group facilitator Four Sets of Analytical Skills –Systems Thinking –Organizational Knowledge –Problem Identification –Problem Analyzing and Solving

29. The Blurred Proportional SDLC 29

30. Methodologies, Tools, and Techniques 30 CASE Tools Systems Architect Alternatives to CASE technologies (VISIO)

31. The Enhanced SDLC 31 The enhanced SDLC embodies several important concepts: The recurring nature of the SDLC The blending of several phases of the SDLC The influence of the user throughout the SDLC The addition of many powerful tools to assist the analyst

32. The Enhanced SDLC 32

33. Chapter Summary (1/3) 33 Small enterprise, PC-based computing should rely on proven systems theory and techniques The small enterprise approach presents special advantages for an introductory study of systems analysis The systems development life cycle provides a framework for creating a small enterprise information system

34. Chapter Summary (2/3) 34 There are five phases of the SDLC: Analysis Design Development Implementation Maintenance There are six components of an information system People Procedures Software Hardware Networks Data

35. Chapter Summary (3/3) 35 A systems analyst is: –An agent of change –A problem solving strategist –A group facilitator Characteristics of a System –Components –Interrelated Components –Boundary –Purpose –Environment –Interfaces –Input –Output –Constraints