1. MANAGING THE DEVELOPMENT AND PURCHASE OF INFORMATION SYSTEMS

2. LEARNING GOALS
Explain the purpose of systems development methodologies.
Describe the major phases of the traditional systems development life cycle.
Describe alternative systems development methodologies and when a company should use them.
Explain how organizations purchase and outsource information systems.

3. Systems Development Methodologies
How to develop the “blueprints” for building an information system
Systems development methodologies (SDM)
The process companies go through to develop and maintain an information system
Improve the systems development process
Lead to high-quality systems

4. Traditional Systems Development Life Cycle (SDLC)
Seven phases (also called the waterfall model)
Planning – Testing
Systems Analysis – Implementation
Systems Design – Maintenance
Development
Usually complete one phase before beginning the next
Problem in later phase may require return to previous phase

6. Planning Feasibility analyses
Technical – Do the technologies exist to solve the problem?
Economic – Can the organization afford the system and will it provide an adequate ROI?
Operational – Assesses the human element of the proposed system
Resistance to change
Organizational politics
Schedule – Is the proposed development time line realistic?

7. Systems Analysis
Systems analyst works with company to understand the problem fully and detail the requirements of the proposed solution
Tools and techniques
Data flow diagrams (DFDs)
Start with high level process
Add more levels with increased levels of detail
Computer-Aided Software Engineering (CASE)
Software that eases the systems development process

9. Detailed Data Flow Diagram

10. Systems Design Describe in detail how to build the system
Logical systems design
Details the system’s functionality
Structure chart – overall, top-down representation of system’s modules
Physical systems design
Specifies all of the actual components used to implement the logical design
Design frozen at end of this phase
Scope creep
Feature creep

11. Development
Programming process is usually the most difficult and time consuming.
Organization may choose to purchase software or outsource the programming tasks.
Flowcharts often used to map program logic.

12. Testing Programmers test modules – stub testing
Development team tests how modules work together – unit testing
System testing
Verification – system works in simulated environment
Validation – system works in real working environment

13. Implementation Data conversion User training Implementation strategy
Direct cutover
Parallel conversion
Pilot testing
Staged conversion

14. Maintenance
Maintenance counts for as much as 80% of the total cost of an information system
Tasks
Correct errors found during implementation
System enhancements
Incremental upgrades
Addition of major new features

15. Problems with Traditional SDLC
SDLC is time consuming
SDLC is costly
SDLC is rather inflexible
SDLC gets users’ inputs ONLY during systems analysis and implementation phases

16. Prototyping
Development team uses limited set of user requirements to quickly build a working model of the proposed system – a prototype.
Users work with prototype and provide feedback.
The development team revises the prototype based on user feedback.
Process continues until the users are satisfied with the system or until system turns out to be not feasible.
Final system developed from prototype.

18. Joint Application Development (JAD)
Workshop that brings together users and development team to define system requirements and develop a prototype
Less time for analysis than SDLC
Helps alleviate conflicting requirements
Greater user involvement leads to greater user acceptance of final system

19. Rapid Application Development (RAD)
Combines JAD, prototyping, and integrated CASE (ICASE) tools to decrease the time for systems development
ICASE – provide code generating capability
Tool can produce a completed program based on the diagrams developed by systems analysts

20. Object-Oriented Analysis and Design (OOAD)
Object focus instead of process focus
OOAD identifies each object in the system and its properties and procedures
Advantages
Reduces time to develop system
Can lead to high-quality systems

21. }here is the difference
Purchasing Software
Commercial off-the-shelf (COTS)
Less expensive
May not contain all the needed features
Phases in COTS SDLC
System planning
Systems analysis
Request for proposals
Proposal evaluation
Implementation
Maintenance
}here is the difference

22. Request for Proposal (RFP)
Details the requirements for the new systems and invites interested parties to submit a proposal for the system
Sections in an RFP
Summary of existing systems
Specific description of the features of the new system
Proposal evaluation criteria
Budget constraints
Timetable for deliverables
Details of other miscellaneous information

23. Evaluating Proposals
Specific requirements
Demonstrations
Benchmarks

24. Outsourcing
Transfers responsibility for a specific information technology function to an outside vendor
Advantages
Specialists provide service at reduced cost
Specialists attract high-quality people in their area
Allows company to focus on core businesses rather than IT
Key component is the Service Level Agreement (SLA)