1. Computers Are Your Future © 2008 Prentice Hall, Inc.

2. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 2 Computers Are Your Future Chapter 13 Systems Analysis and Design

3. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 3 What You Will Learn About What systems analysts do The concept of a system and its life cycle The use of the systems development life cycle (SDLC) The SDLC’s five phases The mistakes of failed information systems development projects The activities in each of the SDLC’s five phases The deliverables in each of the SDLC’s five phases

4. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 4 Systems Analysis Systems analysis is a field concerned with the organized planning, development, and implementation of artificial systems, including information systems.

5. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 5 Systems Analysts: Communication Counts Systems analysts:  Are computer and problem-solving professionals who determine an organization ’ s information system needs  Define the requirements needed to modify an existing system or develop a new one  Identify alternative solutions and assist in the development of a system

6. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 6 Systems Analysts: Communication Counts A systems analyst’s job involves:  Communication  Understanding the organization’s mission  Understanding user needs  Documenting each step of development  Following an organized procedure  Systems development life cycle (SDLC)

7. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 7 Systems  A system is a collection of components organized to accomplish a goal.  An artificial system is constructed by people to serve some purpose.  Systems have a life cycle:  Preliminary design stage  Detailed design stage  Fabrication, assembly, integration, and test stage  Production and customer support stage  Termination and disposal stage

8. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 8 The Systems Development Life Cycle (SDLC) The SDLC is a model used to improve the quality of information systems by providing an organized approach to problem solving.  The core idea of SDLC is to “ Ensure that each step is performed properly before going to the next one. ”

9. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 9 The Systems Development Life Cycle (SDLC) The essential services provided by information systems include:  Recording and tracking transactions  Providing decision-makers with facts and figures  Providing documentation to consumers and suppliers

10. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 10 Avoiding Mistakes  User involvement is crucial.  A problem-solving approach works best.  Good project management skills are needed.  Documentation is required.  Checkpoints help ensure that the project is on track.  The system should be designed for growth and change.

11. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 11 The Waterfall Model The Five Phases of the SDLC Identify problems and opportunities Analyze and document existing system Design system Implement system Support system

12. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 12 The Five Phases of the SDLC 1.Plan: identify problems and opportunities 2.Analyze: analyze and document existing programs 3.Design: design the system 4.Implement: implement the system 5.Maintain: support the system

13. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 13 Phase 1: Identifying the Problem and Opportunities Recognizing the Need  Deficiencies in performance, information quality, economics, security, efficiency, or service are identified.  A request goes to a steering committee, which decides which needs to address.  A project team is appointed and goals are set for the project.

14. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 14 Phase 1: Identifying the Problem and Opportunities Defining the Problem  A problem is the underlying cause of a symptom.  Determining the exact problem is difficult.  An analyst uses information obtained from users and makes a recommendation to modify the existing system or create a new system.

15. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 15 Phase 1: Identifying the Problem and Opportunities Examining Alternative Solutions  The project team looks at possible solutions.  Internally developed systems  Off-the-shelf software  Outsourcing  If a solution can be found, the project proceeds.

16. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 16 Phase 1: Identifying the Problem and Opportunities Developing a Plan  The project leader formulates a project plan.  The plan specifies:  Goal and scope  All activities  Estimated time  Estimated cost  A Gantt chart is created to provide a timeline of activities.

17. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 17 Phase 1: Identifying the Problem and Opportunities Determining Feasibility  Three dimensions :  Technically feasible  Operationally feasible  Economically feasible  Tangible savings include labor costs, services, and materials.  Intangible benefits include increased sales and better information on which to base decisions.

18. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 18 Phase 1: Identifying the Problem and Opportunities Preparing a Project Proposal  Existing system problems are introduced.  Proposed solutions are explained.  Details of the project plan are presented.  The proposal concludes with a recommendation.

19. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 19 Phase 2: Analyzing and Documenting the Existing Information System Analyzing the Existing System  The existing system is documented.  Activities that should be continued are determined.  Problems not identified in Phase 1 are pointed out.

20. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 20 Phase 2: Analyzing and Documenting the Existing Information System Determining the New System ’ s Requirements  The new system ’ s requirements are precisely stated.  The requirements state the innovations necessary for the system to be acceptable.

21. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 21 Phase 3: Designing the System  How the new system will work is the primary concern.  The overall logical design of the project is examined.  How the new system ’ s output will look is specified.  Analysts can use structural analysis and design tools:  Entity-relationship diagram (ERD)  Data flow diagram  Prototyping tool  Project and data dictionaries are created by team members.  Joint application development (JAD) and computer-aided software engineering (CASE) help improve the design phase.

22. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 22 Entity-Relationship Diagram

23. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 23 Data Flow Diagram

24. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 24 Prototyping Tool

25. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 25 Phase 4: Implementing the System Deciding to Buy or Build  Decisions are made as to whether the system is to be developed in-house or outsourced.  For outsourced projects the team sends:  Request for Quotation (RFQ)  Request for Proposal (RFP)

26. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 26 Phase 4: Implementing the System Developing the Software  Programmers use a program development life cycle (PDLC). Testing  Two types of testing:  Application testing  Acceptance testing

27. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 27 Phase 4: Implementing the System Training  Information systems contain computer hardware/software, knowledgeable users, and procedures.  Users are trained in one-on- one training sessions.  Computer-based training uses multimedia, animation, and programmed learning.

28. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 28 Phase 4: Implementing the System Converting Systems  Conversion occurs in the following ways:  Parallel conversion  Pilot conversion  Phased conversion  Direct conversion

29. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 29 Phase 5: Maintaining the System  The new system receives ongoing assistance.  A post-implementation system review determines if the new system has met its goals.  If the new system is found to be deficient, the systems development life cycle begins again.

30. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 30 Chapter 13 Summary  Systems analysts help determine an organization’s information system needs by working closely with both users and management.  Systems analysts can avoid mistakes by:  Involving users  Using a problem-solving approach  Applying project management skills  Keeping thorough documentation  Using checkpoints  Designing the system for growth and change

31. Computers Are Your Future Chapter 13 © 2008 Prentice Hall, Inc.Slide 31 Chapter 13 Summary (continued)  The systems development life cycle (SDLC) was developed to impose order on earlier, haphazard development processes.  The SDLC’s five phases are:  Plan: identify problems and opportunities  Analyze: analyze and document existing programs  Design: design the system  Implement: implement the system  Maintain: support the system