System DevelopmentInformation Systems for Management1 Chapter 9 System Development

Outline System Life Cycle (definition and phases) System Planning (Automation, Business Process Reengineering, Quality improvements - Benchmarking) System development methodologies Installation/conversion methods Systems success & risk factors System DevelopmentInformation Systems for Management2

System DevelopmentInformation Systems for Management3 System Life Cycle Installation These activities/phases can be run in sequence or in iteration. - Waterfall (structured) methodology - Rapid methodologies Construction Systems Planning

System DevelopmentInformation Systems for Management4System DevelopmentInformation Systems for Management4System DevelopmentInformation Systems for Management4 A Rapid Methodology - Prototyping StrengthsWeaknesses Rapid and relatively inexpensiveInappropriate for large complex systems Useful when requirements are uncertain or when end user interface is critical Can gloss over steps in analysis, documentation and testing Promotes user involvement An alternative to sequential development of systems Steps: Identify basic user’s requirements Develop an initial prototype Test prototype & learn from users Revise & enhance prototype

System DevelopmentInformation Systems for Management5 What organizational changes can be accomplished with new system: Automation of manual tasks Business Process Reengineering (BPR) - radical change of organization; process efficiency in focus Quality improvements (Benchmarking – test of compliance with standards) Systems Planning

System DevelopmentInformation Systems for Management6 Systems Analysis Analysis of organizational needs to be met with an information system focusing on 1. data/information as part of jobs and tasks and on data transformation - remember your entity-relationship diagrams? 2. processes working with data Data analysis: define Information Needs Identifies who needs what information, and when, where and how it is needed Collect business documentation, interview users & managers

System DevelopmentInformation Systems for Management7 Systems Design Create IT-based solution for meeting organizational and information needs Design encompasses: Data (usually some database) Processes applied to data (functionality) User Interface Programming/Construction follows (can be putting together of purchased software)

System DevelopmentInformation Systems for Management8 Testing Testing – assessing quality of the developed system Kinds of tests run based on small to large logic: Unit testing (test each program) System testing (tests IS as a whole; e.g., overload the system) Acceptance testing (final testing, evaluated by users)

System DevelopmentInformation Systems for Management9 Installation Methods Direct cutover New system completely replaces old one Parallel installation Old and new system used until the new proves reliable Phased installation New system introduced in stages by function Pilot installation Variation of Phased - new system introduced to a limited area of the organization

System DevelopmentInformation Systems for Management10 Production Stage and Maintenance System is being used for organizational needs Operate the system Evaluate the system Modify the system as needed (Maintenance; e.g., larger data storage needed or queries answering new questions)