Computers Are
Your Future
© 2006 Prentice Hall, Inc.
Computers Are Your Future: Chapter 13
Computers Are Your Future
Chapter 13
Systems Analysis and Design
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
What You Will Learn About
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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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Information Systems
 The information age is all about managing the data –
to provide information and the systems to support
society’s many functions
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Systems Analysis
 The Systems Analysis is a professional who is
charged with the planning, development, and
implementation of information systems
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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)
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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”
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
“Classic Mistakes”
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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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
The Waterfall Model
 The Five Phases of the SDLC
Identify problems
and opportunities
Analyze and
document
existing system
Design system
Implement system
Support system
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
The Five Phases of the SDLC
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4.
5.
Plan: identify problems and opportunities
Analyze: analyze and document existing programs
Design: design the system
Implement: implement the system
Maintain: support the system
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Phase 3: Designing the System
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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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Entity-Relationship Diagram
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Data Flow Diagram
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
Prototyping Tool
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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)
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
Slide 27
Computers Are Your Future: Chapter 13
Phase 4 (continued)
Training
 Information systems contain
computer hardware/software,
knowledgeable users, and
procedures
 Users are trained in one-onone training sessions
 Computer-based training uses
multimedia, animation, and
programmed learning
© 2006Prentice Hall, Inc.
Slide 28
Computers Are Your Future: Chapter 13
Phase 4 (continued)
Converting Systems
 Conversion occurs in the
following ways:
 Parallel conversion
 Pilot conversion
 Phased conversion
 Direct conversion
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
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Computers Are Your Future: Chapter 13
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
© 2006Prentice Hall, Inc.
Slide 31
Computers Are Your Future: Chapter 13
Chapter 13 Summary
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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
© 2006Prentice Hall, Inc.
Slide 32
Computers Are Your Future: Chapter 13
Chapter 13 Summary (continued)
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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
© 2006Prentice Hall, Inc.
Slide 33