Approaches to Systems Building

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Approaches to Systems Building

• Paul FlanaganRegent UniversityFebruary 26, 2001

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Systems Development Process
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Systems Development Life Cycle
Investigation Feasibility Study
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Prototyping Cycle
Identify End User Requirements
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When To Use Prototyping

• Smaller systems
• Single user
• Self contained
• User interfaces
• Flexible requirements
• Reports

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Prototyping Pros and Cons
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End User Development

• Super users
• Simplified toolsets
• MS Office or other
• Word processor
• Spreadsheet
• Database
• Communications
• Presentation

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End User Development Pros and Cons
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Who should develop?
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How can IT help end users?

• Simplify access to data and databases
• Advice and help
• Testing quality control
• Training tutorials
• Backup

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What concepts can help development?

• Information Center ?
• CASE tools
• Object Oriented Programming
• Off-the-shelf software
• Outsource
• Joint development

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CASE Tools
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Object Oriented Programming

• Building blocks for a system
• Not procedural
• Properties (what it has) and methods (what it
  does)
• Classes (general) and instances (specific)
• Key facets
• Encapsulation
• Inheritance
• Polymorphism
• Reusability

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Object Oriented Design
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Object Oriented Communication
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Classes and Instances
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Off The Shelf Pros and Cons
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Customization Blessing or Curse

• Makes system match business process
• May help competitive advantage
• Makes system maintenance difficult
• Troubleshooting
• Patches
• Upgrades
• Need skill sets without full payoff from those
  skills

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Customization Costs
Costs
Customizations
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Customizations NYTCo Finance
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Customizations NYTCo HRMS
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Outsourcing

• Consultants
• Application Service Providers ASP
• Business Process Outsourcing BPO

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Outsourcing SSC Experience

• Not a happy history
• IBM
• DEC / Compaq
• Anderson Consulting

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Joint Applications Development
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Development Lessons Learned

• Early user involvement
• Continuous user involvement
• Test, test, test, test
• Train, train, train, train

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TANSTAAFL
Quality
Time
Cost
Scope