Computers Are Your Future © 2006 Prentice Hall, Inc.

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 2 Computers Are Your Future Chapter 13 Systems Analysis and Design

Computers Are Your Future: Chapter 13 © 2006Prentice 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 4 Information Systems The information age is all about managing the data – to provide information and the systems to support society’s many functions

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 5 Systems Analysis The Systems Analysis is a professional who is charged with the planning, development, and implementation of information systems

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 6 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 7 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)

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 8 Systems A system is a collection of components (hardware and software) organized to accomplish a task 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 9 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 “ Ensure that each step is performed properly before going to the next one ”

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 10 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 11 “Classic Mistakes” End user involvement is crucial A problem-solving approach works best Good project management (PMP ’ s) skills are needed Documentation is necessary Checkpoints help ensure that the project is on track The system should be designed for growth and change

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 12 The Waterfall Model The Five Phases of the SDLC Identify problems and opportunities Analyze and document existing system Design system Implement system Support system

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 13 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 14 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 15 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 16 Phase 1 (continued) 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 17 Phase 1 (continued) 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 18 Phase 1 (continued) 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 19 Phase 1 (continued) 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 20 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 21 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 22 Phase 3: Designing the System How the new system will work is the primary concern The overall logical design of the project is looked at 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 23 Entity-Relationship Diagram

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 24 Data Flow Diagram

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 25 Prototyping Tool

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 26 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)

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 27 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 28 Phase 4 (continued) 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 29 Phase 4 (continued) Converting Systems Conversion occurs in the following ways:  Parallel conversion  Pilot conversion  Phased conversion  Direct conversion

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 30 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 31 Important Terms Information Technology Steering Committee Return on Investment (ROI) Request for Quotation (RFQ) Request for Proposal (RFP) Value-Added Resellers (VARs) Proof of Concept (POC) Acceptance Testing Cost Benefit Analysis

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 32 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

Computers Are Your Future: Chapter 13 © 2006Prentice Hall, Inc.Slide 33 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