Systems Development

1
Chapter 14

• Systems Development

2
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development
• Issues
• FHC System Proposal

3
Reasons for Change

• Deterioration
  (legacy systems)
• Technology
• User expectations
• Keep up with competition
• External forces
• Merger / takeover
• Government regulation

4
IT Life Cycle

• Analysis and design
• Implementation
• Maintenance
• Deterioration or obsolete

5
Development Method

• System development life cycle (SDLC)
• Prototyping
• Rapid application development (RAD)
• Object oriented development
• End user development
• Outsourcing

6
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development
• Issues
• FHC System Proposal

7
System Development Life Cycle (SDLC)

• Distinct IS project segments
• Different with each organization
• Each segment has
• start and end dates
• deliverable

8
System Development Life Cycle

• Feasibility study
• Technology, Economics, organizational factors,
  legal, ethical, and other constraints
• Analysis and design
• User requirements input, output, storage
• Acquisition or development
• Programming, testing, documenting

9
System Development Life Cycle

• Implementation
• Parallel conversion, direct cutover, pilot
  conversion, phased or modular conversion
• Operation
• Post-audit
• System performance
• Maintenance
• Minor changes

10
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development
• Issues
• FHC System Proposal

11
Prototyping

• Model of final IS
• Reasons
• 4GLs
• PCs
• Failure of classic approach

12
Prototype Life Cycle
Analyze problem
Develop Prototype
Operationalize Prototype
Refine Prototype
Complete System
13
Prototyping Types

• Operational prototype or production prototype
• Throwaway prototype

14
Advantages

• User oriented
• What the user sees
• Not enigmatic diagrams
• Quicker error feedback
• Earlier training

15
Disadvantages

• User expectations
• Bypass analysis
• Documentation
• Never ending

16
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development
• Issues
• FHC System Proposal

17
Rapid Application Development

• Special case of Prototyping
• Components
• GUI development environment
• Reusable components
• Code generator
• Object oriented programming language

18
Advantages

• Speed
• Portability
• Maintainability and modifiability
• Data oriented systems

19
Disadvantages

• Never ending
• Lack of documentation
• Inadequate analysis

20
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Objective Oriented Development
• End User Development
• Issues
• FHC System Proposal

21
Object Oriented Development

• Reusable IS components
• Small, self-contained program modules
• Includes
• Operations
• Data

22
Advantages

• Easier to build and maintain (object)
• Reusable codes
• Flexible for adding and changing objects
• User oriented
• Increase productivity and quality (programmer)
• Increase productivity and quality
• Web application

23
Disadvantage

• Complex
• Lack of experts

24
Agenda

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development
• Issues
• FHC System Proposal

25
End User Development

• Reasons
• Powerful PC
• Cheaper hardware
• Software capability
• Computer literate
• IS backlog
• Small application

26
Advantages

• User control
• Business oriented
• Cost saving
• Development speed

27
Disadvantages

• Cost (hardware and software)
• Lack of analysis
• Lack of testing
• No documentation
• Duplication effort
• Security
• Backup and recovery

28
Points to Remember

• Reasons for Change
• System Development Life Cycle (SDLC)
• Prototyping
• Rapid Application Development (RAD)
• Object Oriented Development
• End User Development

29
Discussion Questions

• Will applications programmers and systems
  analysts become nothing more than evaluators of
  packaged software?
• How do you measure System Effectiveness in
  your organization?
• How can you tell when a system is successful?
• unsuccessful?
• How do you decide that a system needs rework?

30
Assignment

• Review chapters 8-14 technology
• Read chapter 15
• Group assignment
• Research paper