Introduction to Systems Development Life Cycle

1. Introduction to Systems Development Life Cycle

2. The Information Systems Life Cycle • What are the four steps in the information systems life cycle (ISLC)? • System development • System implementation • Syetem Operation • System obsolencence

4. The Systems Development Life Cycle • What are the five steps in the systems development life cycle (SDLC)? • Systems analysis • Conceptual design • Physical design • Implementation and conversion • Operations and maintenance

6. The Systems Development Life Cycle: Systems Analysis Systems Analysis Do initial investigation Do system survey Do feasibility study Determine information needs and system requirements Deliver systems requirements Conceptual Design

7. The Systems Development Life Cycle: Conceptual Design Conceptual Design Identify and evaluate design alternatives Develop design specifications Deliver conceptual design requirements Physical Design

8. The Systems Development Life Cycle: Physical Design Physical Design Design output Design database Design input Develop programs Develop procedures Design controls Deliver developed system Implementation and Conversion

9. The Systems Development Life Cycle: Implementation and Conversion Implementation and Conversion Develop plan Install hardware and software Train personnel, test the system Complete documentation Convert from old to new system Fine-tune and review Deliver operational system Operation and Maintenance

10. The Systems Development Life Cycle: Operation and Maintenance Feasibility analysis and decision points: Economic Feasibility Technical Feasibility Legal Feasibility Scheduling Feasibility Operational Feasibility Operation and Maintenance Operate system Modify system Do ongoing maintenance Deliver improved system Systems Analysis

11. The Players • Who are the people involved in developing and implementing IS? • Management • Information systems steering committee • Project development team • Systems analysts and programmers • External players

12. The Players • What are top management’s roles? • providing support and encouragement • establishing system goals and objectives • determine information requirements

13. The Players • What are the steering committee’s roles? • set policies that govern the IS • ensures top-management participation • guidance and control • facilitates coordination and integration of IS activities

14. The Players • What are the project development team’s roles? • plan each project • monitor project • make sure proper consideration is given to the human element

15. The Players • What are the system analyst’s and programmer’s roles? • study existing systems • design new systems and prepare specifications • write computer programs

16. Planning Systems Development • Why is planning an important step in systems development? • consistency • efficiency • cutting edge • lower costs • adaptability

17. Planning Systems Development • What types of systems development plans are needed? • project development plan • master plan

18. Planning Techniques • Two techniques for scheduling and monitoring systems development activities are: • PERT (program evaluation and review technique) • PERT requires that all activities and the precedent and subsequent relationships among them be identified. • Gantt chart • A bar chart with project activities listed on the left-hand side and units of time across the top

19. Planning Techniques: Gantt Chart Project Planning Chart (Sample Gantt Chart) ____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ Activity Week Starting 1 2 3 4 5 6 7 8

20. Gantt Chart

21. PERT Chart

22. Microsoft Project Gantt Chart

23. Microsoft Project PERT Chart

24. Feasibility Analysis • Systems analysis is the first step in the systems development life cycle (SDLC). • A feasibility study(also called a business case) is prepared during systems analysis and updated as necessary during the remaining steps in the SDLC. • The steering committee uses the study to decide whether to terminate a project, proceed unconditionally, or proceed conditionally.

25. Feasibility Analysis • What five important aspects need to be considered during a feasibility study? • Technical feasibility • Operational feasibility • Legal feasibility • Scheduling feasibility • Economic feasibility

26. Feasibility Analysis • Economic feasibility is the most frequently analyzed of the five aspects. • What is the basic framework for feasibility analysis? • capital budgeting model

27. Feasibility Analysis • What are some capital budgeting techniques? • payback period • net present value (NPV) • internal rate of return (IRR)

28. Candidate Systems Matrix

29. Candidate Systems Matrix (cont.)

30. Feasibility Matrix

31. Typical System Proposal Outline • Introduction • Purpose of the report • Background of the project leading to this report • Scope of the report • Structure of the report • Tools and techniques used • Solution generated • Feasibility analysis (cost-benefit) • Information systems requirements • Alternative solutions and feasibility analysis • Recommendations • Appendices

32. Behavioral Aspects of Change • Individuals involved in systems development are agents of change who are continually confronted by people’s reaction and resistance to change. • The best system will fail without the support of the people it serves.

33. Behavioral Aspects of Change • Why do behavioral problems occur? • personal characteristics and background • manner in which change is introduced • experience with prior changes • communication • disruptive nature of the change process • fear

34. Behavioral Aspects of Change • How do people resist IS changes? • aggression • projection • avoidance

35. Behavioral Aspects of Change • How can behavioral problems be overcome? • meet needs of the users • keep communication lines open • maintain a safe and open atmosphere • obtain management support • allay fears • solicit user participation • make sure users understand the system

36. Behavioral Aspects of Change • How can behavioral problems be overcome? (continued) • provide honest feedback • humanize the system • describe new challenges and opportunities • reexamine performance evaluation • test the system’s integrity • avoid emotionalism • present the system in the proper context • control the users’ expectations • keep the system simple

37. Systems Analysis • When a new or improved system is needed, a written request for systems developmentis prepared. • The request describes the current system’s problems, why the change is needed, and the proposed system’s goals and objectives. • It also describes the anticipated benefits and costs.

38. Sample Request for System Services

39. Sample Problem Statements

40. Systems Analysis • There are five steps in the analysis phase: • Initial investigation • Systems survey • Feasibility study • Information needs and systems requirements • Systems analysis report

41. Computer-Aided Software Engineering (CASE) • CASE is an integrated package of computer-based tools that automate important aspects of the software development process. • CASE tools are used to plan, analyze, design, program, and maintain an information system. • They are also used to enhance the efforts of managers, users, and programmers in understanding information needs.

42. Computer-Aided Software Engineering (CASE) • CASE tools do not replace skilled designers; instead they provide a host of self-integrated tools that give developers effective support for all SDLC phases. • CASE software typically has tools for strategic planning, project and system management, database design, screen and report layout, and automatic code generation.

43. CASE Tool Architecture

44. Computer-Aided Software Engineering (CASE) Advantages of CASE Technology Improved productivity Improved program quality Cost savings Improved control procedures Simplified documentation

45. Computer-Aided Software Engineering (CASE) Disadvantages of CASE Technology Incompatibility Cost Unmet expectations

46. Systems Design, Implementation, and Operation

47. Conceptual Systems Design • In the conceptual systems design phase, a general framework is developed for implementing user requirements and solving problems identified in the analysis phase. • What are the three steps in conceptual design? • Evaluate design alternatives. • Prepare design specifications. • Prepare conceptual systems design report.

48. Conceptual Systems Design Systems analysis Evaluate design alternatives Prepare design specifications Prepare conceptual systems design report

49. Conceptual Systems Design • Evaluate design alternatives: • The design team should identify and evaluate design alternatives using the following criteria: • How well it meets organizational and system objectives • How well it meets users’ needs • Whether it is economically feasible • Its advantages and disadvantages

50. Conceptual Systems Design • Prepare design specifications: • Once a design alternative has been selected, the team develops the conceptual design specificationsfor the following elements: • Output • Data storage • Input • Processing procedures and operations