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Chapter 15 Systems Development. Why Develop an IS?. Three phenomena that trigger IS development An opportunity (proactive) A problem (reactive) A directive. The systems development life cycle. The Systems Development Life Cycle (SDLC). The Systems Development Life Cycle ( SDLC ). Analysis
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Why Develop an IS? • Three phenomena that trigger IS development • An opportunity (proactive) • A problem (reactive) • A directive
The systems development life cycle The Systems Development Life Cycle (SDLC)
The Systems Development Life Cycle (SDLC) • Analysis • Determines what need the system will satisfy • Investigation • Developers interview managers and perspective users to determine business needs. • Three feasibility studies performed.
The Systems Development Life Cycle (SDLC) • The Technical Feasibility Study • Ensures hardware and software exist to build the system • The Economic Feasibility Study • Benefits of the system weighed against the cost • The Operational Feasibility Study • Determines if system will be used as intended
Phases in systems design The Systems Development Life Cycle (SDLC) • Design Logical Design • Translation of user requirements into detailed functions of the system Physical Design Construction Systems Testing
The Systems Development Life Cycle (SDLC) • Implementation • Training • Conversion • Parallel Conversion • Phased Conversion • Cold Turkey Conversion • Pilot Conversion
Activities in systems support The Systems Development Life Cycle (SDLC) • Support
Prototyping • Systems developed using an Iterative Process • Purpose is to develop a working model as quickly as possible, which can be tweaked and revised • Significantly shortens systems development backlog • Can increase risk of incompatibility and other unforeseen mishaps
When to prototype and when not to prototype In prototyping, refinement of the system continues until users are satisfied. Prototyping
Dimensions of project management IS development projects: challenges and failures Project Management • Project Management Goals • Complete the project on time. • Complete the project within budget. • Meet requirements. • Meet expectations.
Project Management • Project Management Functions • Communication Management • Schedule Management • Quality Management • Financial Management • Resource Management
The six steps of JAD Systems DevelopmentLed by End Users • JAD:An example of User-led Systems Development • Joint Application Development (JAD): method to be used in SDLU • Uses six-step process to take the team through planning and design
Systems DevelopmentLed by End Users • JAD Critical Success Factors • All participants must be committed to JAD process. • Customers and IS people must agree on project’s scope. • Sponsor must be supportive and involved. • Team members must be empowered decision makers. • Business objectives must be clearly defined. • Business process must be understood. • Team members must be able to meet two or more days per week. • Members must be committed to the team.
Outsourcing • Short-term contractualrelationship with a service firm to develop a specific application • Long-term contractualrelationship with a service firm to take over all or some of an organization’s IS functions
Advantages of Outsourcing • Improved financial planning • Reduced license and maintenance fees • Increased attention to core business • Shorter implementation cycles • Reduction of personal and fixed costs • Increased access to highly qualified know-how? • Increased security
Outsourcing • Risks of Outsourcing • Loss of control • Loss of experienced employees • Risks of losing a competitive advantage
Risks of outsourcing are higher at higher levels of management. Outsourcing IT 3133
The InformationSystems Subsidiary • IS service companies that are owned by and served by one large company • Some grow large enough to service the market at large • Some corporations purchase an IS consulting firm
Purchased Applications • Why Purchase? • Immediate system availability • High quality • Low price • Available support
Purchased Applications • Purchasing Risks • Loose fit between needs and features • Bankruptcy of the vendor • High turnover of vendor personnel
Renting Software • On-site Renting • Client purchases a license to use a certain application for a specified time • Renting Through the Web • Application installed at vendor’s location; client accesses through the Web or leased line
Benefits and risks of software rental through the Web Renting Software
User Application Development • Factors Encouraging User Application Development • The widespread use of PCs • The emergence of 4GLs • Increasing popularity of prototyping • Increasing popularity of client/server architecture
User Application Development • Advantages of user application development • Shortened lead times • Good fit to needs • Free IS staff time
User Application Development • Risks of user application development • Poorly developed applications • Duplication • Security problems • Poor documentation