Chapter 10: Systems Development

1. Chapter 10: Systems Development Succeeding with Technology: Second Edition

2. Objectives • Describe the systems development life cycle, who participates in it, and why it is important • Discuss systems development tools • Understand how systems development projects are investigated Succeeding with Technology

3. Objectives (continued) • Describe how an existing system can be evaluated • Discuss what is involved in planning a new system • List the steps to implement a new or modified system • Describe the importance of updating and monitoring a system Succeeding with Technology

4. An Overview of Systems Development • Systems development process • Typically called a systems development life cycle (SDLC) • Systems investigation and analysis • Looks at the existing system and determines if it can and should be improved Succeeding with Technology

5. An Overview of Systems Development (continued) • Systems design and implementation • Modifying an existing system or developing a new one • Maintenance and review • Makes sure that the new or modified system is operating as intended Succeeding with Technology

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7. Participants in Systems Development • System stakeholders • Individuals who will benefit from systems development project • Users • Individuals who will be interacting with the system on a regular basis • Managers • People most capable of initiating and maintaining change • Systems analyst • Specializes in analyzing and designing systems Succeeding with Technology

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9. Why Start a Systems Development Project? • Creative analysis • Investigating new approaches to existing problems • Critical analysis • Being skeptical and doubtful • Questioning whether or not the current computer system is still effective and efficient • Systems development process • Begins with gathering information on users’ needs Succeeding with Technology

10. End-User Systems Development • The development of computer systems by • Individuals outside of the formal computer systems planning and departmental structure • Systems developed by end users • Range from the very small to those of significant organizational value Succeeding with Technology

11. Tools and Techniques for Systems Development • Systems development tools • Can greatly simplify the systems development process • Include • Computer-aided software engineering tools • Flowcharts, decision tables • Project management tools, prototyping, • Outsourcing, and object-oriented systems development Succeeding with Technology

12. Computer-Aided Software Engineering • Software engineering • Employs computer-aided software engineering (CASE) tools • CASE tools • Automate many systems development tasks • Allow more than one person to work on the same system at the same time via a multiuser interface Succeeding with Technology

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14. Flowcharts • Reveal the path from a starting point to the final destination • Can display various amounts of detail • When developing a system • General flowchart describes the overall purpose and structure of the system Succeeding with Technology

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17. Decision Tables • Can be used as an alternative to or in conjunction with flowcharts • In general, a decision table displays • The various conditions that could exist • The different actions that the computer should take Succeeding with Technology

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19. Project Management Tools • Purpose is to plan, monitor, and control necessary development activities • Program Evaluation and Review Technique (PERT) • Creates three time estimates for an activity • The shortest possible time • The most likely time • The longest possible time • Gantt charting • A grid that lists activities and deadlines Succeeding with Technology

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21. Prototyping • The creation of a preliminary model or version of a major subsystem • Iterative approach to systems development • Each phase of the SDLC is repeated several times (iterated) Succeeding with Technology

22. Outsourcing • Use of outside company to take over portions of its workload • Guidelines to make outsourcing a success • Keep tight controls on the outsourcing project. • Treat outsourcing companies as partners • Start with smaller outsourcing job • Create effective communications channels between the organization and the outsourcing company Succeeding with Technology

23. Object-Oriented Systems Development • An extension of object-oriented programming • Can be used during all phases of systems development • Organizations • Have saved time and money using the object-oriented approach to systems development Succeeding with Technology

24. Systems Investigation • Overall purpose • Determine whether objectives of existing system satisfy the goals of the organization • Attempts to answer the following questions • What primary problems might a new or enhanced system solve? • What opportunities might a new or enhanced system provide? • What are the potential costs? • What are the associated risks? Succeeding with Technology

25. Feasibility Analysis • Technical feasibility • Concerned with whether or not hardware/software can be acquired or developed to solve the problem • Economic feasibility • Determines if the project makes financial sense • Legal feasibility • Determines whether laws or regulations may prevent or limit a systems development project Succeeding with Technology

26. Feasibility Analysis (continued) • Operational feasibility • Measure of whether or not the project can be put into action or operation • Schedule feasibility • Determines if the project can be completed in a reasonable amount of time Succeeding with Technology

27. Systems Analysis • Attempts to understand how the existing system helps solve the problem identified in systems investigation • Overall emphasis • To gather data on the existing system and the requirements for the new system • To consider alternative solutions to the problem and the feasibility of the solutions Succeeding with Technology

28. General Analysis Considerations • Formalized analysis procedure involves • Collecting appropriate data • Analyzing the data • Determining new system requirements and project priorities Succeeding with Technology

29. Collecting Data • Purpose • To seek additional information about problems identified during systems investigation • Techniques • Interviews • Direct observation • Outputs • Questionnaires • Other Data Collection Methods Succeeding with Technology

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32. Requirements Analysis • Purpose • To determine user, stakeholder, and organizational needs • Tools and techniques • Asking Directly • Critical Success Factors • Joint Application Development • Rapid Application Development Succeeding with Technology

33. Systems Design • Overall purpose • To select and plan a system that meets the requirements needed to deliver the problem solution • Results • A new or modified system Succeeding with Technology

34. Generating Systems Design Alternatives • First step of design • Investigate alternatives for all components • Request for information (RFI) • Asks a computer systems vendor to provide information about its products or services • Request for quotes (RFQ) • Asks a computer systems company to give prices for its products or services • Request for proposal (RFP) • Generated during systems development Succeeding with Technology

35. Systems Implementation • Includes • Hardware acquisition • Software acquisition or development • User preparation • Hiring and training of personnel • Site and data preparation • Installation, testing, startup, and user acceptance Succeeding with Technology

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37. Acquiring Hardware • Most people and organizations acquire hardware and computers by • Purchasing, leasing, or renting computer resources from a computer systems vendor • “Pay as you go computing” • Organization pays only for the computer power it uses Succeeding with Technology

38. Selecting and Acquiring Software:Make, Buy, or Rent • Program specification • Description of what the software must accomplish • Algorithm • Step-by-step sequence of computer instructions • Syntax errors • Errors in the use of the programming language syntax • Logic errors • Errors in the programming logic Succeeding with Technology

39. Acquiring Database and Telecommunications Systems • A database is one of the most important parts of system development • Many projects involve a database • May require both hardware and software acquisition • Telecommunications is one of the fastest growing business applications • May require both hardware and software acquisition Succeeding with Technology

40. User Preparation • Readying users and stakeholders for the new or modified system • Can include • Marketing • Training • Documentation • Support Succeeding with Technology

41. Site Preparation • Location of the new system needs to be prepared • For a small system • May mean rearranging the furniture • Larger systems • May require special wiring and air conditioning Succeeding with Technology

42. Data Preparation • Converting manual files into computer files • Data conversion • May be required to transform the existing computerized files into the proper format • Permanent data • Must be placed on a permanent storage device Succeeding with Technology

43. Installation • Placing computer equipment on the site and making it operational • For a small systems development project • May require making room on top of a desk for a new PC • Plugging it into a wall outlet • Following the manufacturer’s instructions to turn it on Succeeding with Technology

44. Testing • Unit testing • Developing test data that will force the computer to execute every statement in the program • System testing • Requires the testing of all programs together • Volume testing • Ensures that entire system can handle a large amount of data under normal operating conditions Succeeding with Technology

45. Testing (continued) • Integration testing • Ensures that new programs can interact with other major applications • Acceptance testing • Ensures that new or modified system is operating as intended Succeeding with Technology

46. Startup • Direct conversion • Stopping the old system and starting the new one on a given date • Phase-in approach • New system is slowly phased in, while old one is slowly phased out • Pilot startup • Running a pilot or small version of the new system along with the old Succeeding with Technology

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48. User Acceptance and Documentation • User acceptance document • Agreement signed by user that a phase of the complete system is approved • Documentation • Includes all materials that describe the new or modified system Succeeding with Technology

49. User Acceptance and Documentation (continued) • Systems documentation • Describes the technical aspects of the new or modified system • User documentation • Describes how the system can be used by noncomputer personnel Succeeding with Technology

50. Systems Maintenance and Review • Final steps of systems development • Involves checking, changing, and enhancing the system Succeeding with Technology