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Information Systems Development Methods

Information Systems Development Methods. Panagiotis Kanellis , Επιστημονικός Συνεργάτης Τμήματος Πληροφορικής ΕΚΠΑ Business Consulting , 377 Syngrou Ave. , 175 64 Athens , Greece Email: kanellis@di.uoa.gr. Δρακούλης Μαρτάκος , Επίκουρος Καθηγητής Τμήματος Πληροφορικής ΕΚΠΑ

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Information Systems Development Methods

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  1. Information Systems Development Methods Panagiotis Kanellis, Επιστημονικός Συνεργάτης Τμήματος Πληροφορικής ΕΚΠΑ Business Consulting, 377 Syngrou Ave., 175 64 Athens, Greece Email: kanellis@di.uoa.gr Δρακούλης Μαρτάκος, Επίκουρος Καθηγητής Τμήματος Πληροφορικής ΕΚΠΑ Κτίρια Πληροφορικής, Πανεπιστιμιόπολη, 157 84Αθήνα Email: martakoσ@di.uoa.gr

  2. Learn about... • The Traditional Systems Life Cycle • Prototyping • Developing with Application Software Packages • End-User Development • Outsourcing Information Systems

  3. The Traditional Systems Life Cycle • Oldest method for building information systems • Still used today for complex medium/large system projects • Traditional methodology for developing an IS that partitions the systems development process into six formal stages that must be completed sequentially with a very formal division of labor between end users and information systems specialists

  4. Stages of the Systems Life Cycle • Project Definition • Systems Study • Design • Programming • Installation • Post-Implementation

  5. Limitations of the Life Cycle Approach • Very resource intensive • Is inflexible and inhibits change • Ill suited to decision-oriented applications

  6. Prototyping • Process of building an experimental system quickly and inexpensively for demonstration and evaluation so that end users can better determine information requirements • It is an iterative process

  7. Steps in Prototyping • Identify the user’s basic requirements • Develop a working prototype • Use the prototype • Revise and enhance the prototype When no more iterations are required, the approved prototype then becomes an operational prototype that furnishes the final specifications for the application

  8. Developing Systems with Application Software Packages Set of prewritten, precoded application software programs that are commercially available for sale or lease • Where functions are common to many companies • Where information systems resources for in-house development are in short supply • When desktop microcomputer applications are being developed for end-users

  9. Advantages of Applications Software Packages • Most of the design work has been accomplished in advance • Fewer internal information systems resources are necessary to support a package-based system • Reduce some of the organizational bottlenecks in the systems development process (users have to accept it as is)

  10. Disadvantages of Applications Software Packages • Have not yet achieved the level of sophistication and technical quality needed to produce multipurpose packages • May not meet all of an organization’s requirements • Extreme customization may result in the package becoming unrecognizable • Vendor may stop providing support

  11. Selecting Software Packages • Request for Proposal (RFP) - Detailed list of questions submitted to vendors of packaged software or other computer services to determine if the vendor’s product can meet the organization’s specific requirements

  12. Application Package Development Cycle

  13. End-User Development The development of IS by end users with little or no formal assistance from technical specialists • made possible by the 4th-generation software tools • users can access data, create reports, create web pages without professional help • the role of IS specialist becomes supportive • systems can be created very rapidly

  14. Advantages/Disadvantages of 4th Generation Tools • Productivity gains of 300 to 500% • Capabilities remain limited • Require large amounts of computing resources • Slow response times for high volume processing 4th generation tools are most likely to create systems rapidly and effectively when system builders lay the appropriate groundwork

  15. Benefits and Problems of End-user Development • Improved requirements determination • User involvement and satisfaction • Control of the systems development process by users • Reduced application backlog • Insufficient review and analysis when user and analyst functions are no longer separate • Lack of proper quality assurance standards and controls • Uncontrolled data • Proliferation of “private” information systems

  16. Policies and Procedures to Manage End-User Computing • Cost justification of end-user information systems projects • Hardware and software standards for user-developed applications • Company-wide standards for microcomputers, word processing software, DBMS, graphics software, and query reporting tools • Quality assurance reviews, specifying whether only individual and users or whether specialists from the information systems or internal audit departments should review end-user developed applications • Controls for end-user developed applications covering testing, documentation, accuracy, and completeness of input and update, backup, recovery, and supervision

  17. Outsourcing Information Systems The practice of contracting computer center operations, telecommunication networks, or applications development to external vendors • Economy Loss of control • Service Quality Vulnerability of Strategic Information • Predictability • Flexibility • Making fixed costs variable • Freeing up human resources for other projects • Freeing up financial capital

  18. When to Use Outsourcing • When there is only a limited opportunity for the firm to distinguish itself competitively through a particular information systems application or a series of applications • When outsourcing does not strip the company of the technical know-how required for future information systems innovation • When the firm’s existing information systems capabilities are limited, ineffective, or technically inferior

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