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Chapter 1
Introduction
Jerry Post
Copyright © 1997
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Purpose of This Class
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S  Systems development and programming is hard.
T  Many failures in the past and recently.
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 Over budget.
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 Over schedule.
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 Total failure/not completed.
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 Teamwork
 Large projects require teams of MIS workers.
 Need to split project into pieces, coordinate workers.
 Need to share and communicate.
 Need to control and evaluate progress.
 Design characteristics, tips, and tricks.
 Planning and scheduling.
 Tools.
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Runaway Projects

Technical measures
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2 - 5 times over budget
2 - 5 times behind
schedule
Missing technical
objectives
Design problems



Duplication of efforts
Incompatibilities
User/designer conflicts
$
1994
1996
1998
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Project Success and Failure
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 Reasons for Success
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 Lack of user input
 User Involvement
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 Incomplete requirements
 Executive management
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support
 Changing requirements and
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specifications
 Clear requirements
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 Lack of executive support
 Proper planning
 Lack of technical skills
 Realistic expectations
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Development Trends
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 New tools
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 Don’t meet deadlines.
 Project management
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 Go over budget.
 Groupware for sharing
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 Can’t control large projects.
 CASE: Computer-aided
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software engineering
 Programmers are
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expensive.
 Database management
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 You can buy really good
software today.
 Transaction processing.
 Common applications.
 How long does software
last?
 Outdated? Functions and
needs change.
 Depends on hardware.
systems
 Powerful languages (Visual
Basic)
 The Internet!
 User Interface!
 A new way of looking at
development: object-oriented
design
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Business Decisions
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S  Information is a valuable resource.
T  Information systems are used to
make business decisions.
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 Operations
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 Tactics
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Strategic
 Strategy
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 Information Systems
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Transaction Processing
Process Control
Decision Support Systems
Expert Systems
Enterprise Information Systems
Mgt.
Tactical
Management
Business Operations
 Sharing information
 Group Decision Support
 Groupware tools
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The Role of the Analyst
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S  Analyze and Design Systems
 Identify problems, opportunities,
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objectives.
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 Analyze information flows.
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 Design computerized systems to
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solve problems.
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Problem solving.
Communication.
Change agent.
Control, planning, and structure.
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Systems Development Life Cycle
Feasibility &
Planning
Goals & plans
Systems
Analysis
Proposal
Problems &
Improvements
Business requirements
Systems
Design
Technical Design
Systems
Implementation
New System
Existing System
problems
revisions problems
revisions
Systems Maintenance: Incremental changes
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Design Stages
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 Physical Design
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 Scope
 Table definitions
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 Feasibility
 Application development
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 Cost & Time estimates
 Data storage
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 Security
S  Requirements Analysis
 User Views & Needs
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 Forms
 Reports
 Processes & Events
 Objects & Attributes
 Conceptual Design
 Models
 Data flow diagram
 Entity Relationships
 Objects
 Procedures
 Implementation
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Training
Purchases
Data conversion
Installation
 Evaluation & Review
 User feedback
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SDLC Strengths and Weaknesses
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 Disadvantages
S  Advantages
 Control & targets
 Increased costs
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 Formality
 Increased time
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 Financial controls
 Hard for DSS
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 User input
 Requires definitions up front
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 Documentation
 Testing
 Ease of maintenance
 Rigid
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Computer Assisted Software Engineering
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 CASE tool possibilities
 Case complications
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 Personal productivity
 Expensive
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 Diagrams
 No standards
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 Store & Search
 Complex software, learning
 Team productivity
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 Team must follow methodology.
 Sharing up-to-date changes
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 CASE Levels
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 One shared source of data
 Communication
 Development
 Reverse engineering
 Automated programming
 Maintenance
 Complete records for future
 Diagrams and context
 Reverse engineering
 Upper: front-end
 Lower: back-end
 CASE tool examples
 IEF
 Oracle
 Designer 2000
 Developer 2000
 Rational Rose
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