Systems Development Life Cycle

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  • Energy Thanks for the opportunity Small world - Heather Radford - extremely sharp, helpful student assistant - Jim 3M - long time - Galen Britz, others through AIChE Bob Nelson & Cheri Anderson - dental web site This is the results of our onngoing research Conceptual framework - idea of evolution remember your basic business principles apply new IT to principles Practices may be different, revolutionary Disintermediation
  • Energy Thanks for the opportunity Small world - Heather Radford - extremely sharp, helpful student assistant - Jim 3M - long time - Galen Britz, others through AIChE Bob Nelson & Cheri Anderson - dental web site This is the results of our onngoing research Conceptual framework - idea of evolution remember your basic business principles apply new IT to principles Practices may be different, revolutionary Disintermediation
  • Systems Development Life Cycle

    1. 1. Systems Development Life Cycle <ul><li>Introducing the SDLC ( Systems Development Life Cycle) </li></ul><ul><li>First Step: Strategic Analysis (of the Business) and Prioritization of Projects </li></ul><ul><ul><li>Strategic Importance </li></ul></ul><ul><ul><li>Extent of Problem or Opportunity </li></ul></ul><ul><li>Analysis and Design (Prototyping) </li></ul><ul><li>Construction </li></ul><ul><li>Implementation </li></ul><ul><li>Projects 1-5 </li></ul><ul><ul><li>Cover the SDLC through Analysis and Design </li></ul></ul><ul><ul><li>Illustrate the roles, responsibilities, and necessary interaction of IS and non-IS people </li></ul></ul>
    2. 2. IS Development Life Cycle (BUILDING IS ) Global Information System Architecture BUSINESS AREA Analysis (Process/Data Flow Diagrams) DATABASE DESIGN (Data Model Diagram) Computers & Communication Networks INFORMATION SYSTEM DESIGN - Application Processes - User Interfaces (Forms+) DATABASE (Related Tables) CODE STRATEGIC Competitive ANALYSIS generate execute read/write define & populate information requirements PROCESSES DATA PLATFORM Planning USER INTERFACE
    3. 3. Information Systems Development Life Cycle PLANNING & ANALYSIS DESIGN (MODELING) CONSTRUCTION (GENERATION) OPERATION & MAINTENANCE PRIORITIES, SCOPE DESIGN DATABASE &quot;REPOSITORY&quot;
    4. 4. Traditional SDLC ISDEV
    5. 5. The Systems Development Life Cycle (SDLC) <ul><li>PLANNING - global architectures, scoping, setting priorities </li></ul><ul><li>ANALYSIS - feasibility (technical, economic, operational), - cost/benefit, - requirements - ( WHAT ) </li></ul><ul><li>DESIGN (synthesis) - ( HOW ) Conceptual (business solution)  Detailed design (IS solution) </li></ul><ul><ul><li>Process modeling (DFD’s) </li></ul></ul><ul><ul><li>Data modeling (ER Diagrams) </li></ul></ul><ul><ul><li>User Interface (windows, menus, queries, forms, reports...) </li></ul></ul><ul><ul><li>Platform design (Computers + Communication Networks) </li></ul></ul><ul><li>CONSTRUCTION - definitions, programming, - ( BUILD IT ) - testing (unit, system, acceptance) </li></ul><ul><li>INSTALLATION - conversion (direct cutover, parallel, pilot/phased) </li></ul><ul><li>PRODUCTION / OPERATION -- </li></ul><ul><li>POST-IMPLEMENTATION REVIEW </li></ul><ul><li>MAINTENANCE & ENHANCEMENT [& REPLACEMENT] </li></ul>
    6. 6. SDLC - Overview and Metaphors <ul><li>Phase 1 </li></ul><ul><ul><li>Project Identification and Selection </li></ul></ul><ul><ul><li>Information Requirements & Systems Analysis </li></ul></ul><ul><ul><li>System Design </li></ul></ul><ul><li>Phase 2 </li></ul><ul><ul><li>Construction, Testing </li></ul></ul><ul><ul><li>Implementation </li></ul></ul><ul><ul><li>Operation, Support, Maintenance </li></ul></ul><ul><li>QA – throughout </li></ul><ul><ul><li>Get requirements right </li></ul></ul><ul><ul><li>Develop test cases </li></ul></ul><ul><ul><li>Minimize errors and cost </li></ul></ul><ul><ul><li>Maximize satisfaction and effectiveness </li></ul></ul>
    7. 7. A Marketing View of Information Systems <ul><li>SDLC – Life Cycle Model of IT Applications </li></ul><ul><li>Consumer Product Development – A Metaphor for IT Applications </li></ul><ul><li>Software Requirements Determination </li></ul><ul><ul><li>MIS Theories 1 & 2 </li></ul></ul><ul><li>Systems Analysis & Design </li></ul><ul><li>Phased/Adaptive Development - &quot;Learning&quot; </li></ul><ul><li>Testing & QA </li></ul><ul><li>Implementation </li></ul><ul><li>Operation </li></ul><ul><li>Maintenance and Continual Improvement </li></ul><ul><li>Project Success Factors </li></ul>
    8. 8. Cake & Frosting
    9. 9. Consumer Product Development Metaphor <ul><li>Consumer Product Development Attributes </li></ul><ul><li>20 - 30% Success Rate </li></ul><ul><ul><li>Find and Kill Failures Early </li></ul></ul><ul><li>Evolution of successes throughout life cycle </li></ul><ul><ul><li>Profit & quality improvement </li></ul></ul><ul><ul><li>Proliferation </li></ul></ul><ul><li>Tie directly to business objectives </li></ul><ul><li>Lots of up-front time defining the product </li></ul><ul><li>Wide variety, series of Prototypes </li></ul><ul><li>Measurement & Iteration </li></ul><ul><li>Pilots for scale-up </li></ul><ul><li>KEY Players on the Team </li></ul><ul><li>Mix of creativity, new ways, business analysis, marketing, expectations, manufacturing </li></ul><ul><li>Brand Management model – Matrix </li></ul>
    10. 10. Evaluation - Formal Product and Market Research Methods <ul><li>Focus groups </li></ul><ul><li>Expert panels </li></ul><ul><li>Consumer panels </li></ul><ul><li>&quot;Church basement&quot; product evaluations </li></ul><ul><li>Mall intercepts </li></ul><ul><li>In-home tests </li></ul><ul><li>Mail consumer panels </li></ul><ul><li>Opinion research </li></ul><ul><li>Attitude and purchase intent measurement </li></ul><ul><li>Secondary databases </li></ul><ul><li>Store scanner databases for product tracking </li></ul>
    11. 11. Model of an IT Application
    12. 12. Determining Information Requirements <ul><li>Two IS Theories </li></ul><ul><ul><li>#1 - Managers do not know what information they need </li></ul></ul><ul><ul><li>#2 - Most of the information you need to make a decision comes from outside your area </li></ul></ul><ul><li>Four major mistakes in determining information requirements </li></ul><ul><ul><li>Viewing applications as functional </li></ul></ul><ul><ul><ul><li>Cross-functional, one function doesn’t know everything </li></ul></ul></ul><ul><ul><li>Conducting individual interviews </li></ul></ul><ul><ul><ul><li>Limited perspective </li></ul></ul></ul><ul><ul><li>Asking wrong questions </li></ul></ul><ul><ul><ul><li>Asking them - assumes they know! </li></ul></ul></ul><ul><ul><ul><li>Catalog - they ask for all </li></ul></ul></ul><ul><ul><li>Not allowing trial-and error </li></ul></ul><ul><ul><ul><li>We must “learn&quot; our requirements </li></ul></ul></ul>
    13. 13. Approaches to Get Information Requirements Right <ul><li>1. View systems as cross-functional </li></ul><ul><ul><li>Conduct joint application design – multifunction </li></ul></ul><ul><li>2. Broaden the perspective of input </li></ul><ul><ul><li>Group vs. individual interviews </li></ul></ul><ul><li>3. Ask Right Questions - Structured Interviews </li></ul><ul><ul><li>CSFs - focus on business priorities </li></ul></ul><ul><ul><li>Ends & means - effectiveness & efficiency focus </li></ul></ul><ul><ul><li>Decisions – data needed and methods used </li></ul></ul><ul><ul><li>Describe your business process – steps, decisions, data, errors, options and exceptions </li></ul></ul><ul><ul><li>Each of these help get at information requirements of process, data and interfaces </li></ul></ul><ul><li>4. Provide means to help people learn their requirements </li></ul><ul><ul><li>Prototyping (Phased-Adaptive Development) </li></ul></ul><ul><ul><li>Learn from hands-on experience </li></ul></ul><ul><ul><li>View change positively vs. an enemy </li></ul></ul><ul><ul><li>Set user expectations & involvement </li></ul></ul>
    14. 14. Ends & Means Questions <ul><li>Efficiency What is key to achieving efficiency? How do you measure your efficiency? </li></ul><ul><li>Effectiveness What is key to operating effectively? How do you measure your effectiveness? </li></ul><ul><li>What kinds of information help you achieve or measure effectiveness or efficiency? </li></ul><ul><li>Relate these questions to CSFs </li></ul>
    15. 15. Decision Questions <ul><li>What kinds of decisions must you make - by business process? How important are those decisions? How frequently do they occur? </li></ul><ul><li>What information will help you make those decisions? How often do you not have which information? </li></ul><ul><li>Relate these questions and information needs to CSFs </li></ul>
    16. 16. Cost of Fixing System Defects
    17. 17. System Requirements & Design – Primary Source of &quot;Defects&quot; in Systems <ul><li>2/3 of &quot;System Defects&quot; occur in the requirements and design phases </li></ul><ul><ul><li>Not doing the &quot;Right Thing&quot;, </li></ul></ul><ul><ul><li>Or not doing it the &quot;Right Way” </li></ul></ul><ul><li>Problems: </li></ul><ul><ul><li>Very high levels of maintenance and cost </li></ul></ul><ul><ul><li>Projects are late </li></ul></ul><ul><ul><li>Projects are over budget </li></ul></ul><ul><ul><li>People are unhappy and not satisfied with the system or IS </li></ul></ul><ul><li>Objectives and Actions: </li></ul><ul><ul><li>1. Emphasize getting the requirements right, sooner - prototype, JAD, ask helpful questions, broad perspective </li></ul></ul><ul><ul><li>2. Find the errors sooner - QA and testing process </li></ul></ul><ul><ul><li>3. Reduce the cost of fixing the errors - development tools, flexible design, QA and testing process </li></ul></ul>
    18. 18. Concepts about the SDLC process <ul><li>Phased / adaptive development </li></ul><ul><li>Phased implementation </li></ul><ul><li>Expectations - managing & meeting </li></ul><ul><li>Prototypes </li></ul><ul><ul><li>Education, demos, breadth </li></ul></ul><ul><li>Construction and testing </li></ul><ul><li>Pilot and scale-up </li></ul><ul><li>Evaluation </li></ul><ul><ul><li>Throughout, particularly prior to rollout </li></ul></ul><ul><ul><li>Group evaluation using marketing research methods </li></ul></ul><ul><li>Rollout </li></ul><ul><ul><li>Expect and seek out problems </li></ul></ul><ul><ul><li>Deal quickly with problems </li></ul></ul><ul><li>Anticipate and plan for continued development & change </li></ul>
    19. 19. Output of Requirements Determination (P1) <ul><li>Relationship between Business and System Priorities </li></ul><ul><li>General Requirements of the System </li></ul><ul><li>User Expectations </li></ul><ul><li>Users and MIS people must then work as a team to make sure the &quot;specifications&quot; of a proposed system are &quot;correct&quot;, both in terms of WHAT the system is to do, and HOW it is to do it. </li></ul><ul><li>Users must &quot;Correct&quot; the Analysts' Representations </li></ul><ul><li>Next step is systems analysis </li></ul>
    20. 20. Systems Analysis & Design (P2-5) <ul><li>Study and model the existing business processes, information systems and information flows </li></ul><ul><ul><li>Data flow diagrams, process flow diagrams, etc. </li></ul></ul><ul><ul><li>Communication vehicle between stakeholders and implementers </li></ul></ul><ul><ul><li>What changes should be made to the processes? </li></ul></ul><ul><li>Study and model the data requirements, and determine the data creators, users and owners </li></ul><ul><ul><li>Entity relationship diagrams </li></ul></ul><ul><ul><li>“ Normalize” the data base for input efficiency </li></ul></ul><ul><ul><li>Communication vehicle between stakeholders and implementers </li></ul></ul><ul><li>Prototype to determine the primary interfaces for the variety of users of the application (input and output) </li></ul>
    21. 21. Systems Analysis & Design Models <ul><li>Process Design - (Project 2) </li></ul><ul><ul><li>WHAT the system does </li></ul></ul><ul><ul><li>Process Model (Data Flow Diagram - Context) </li></ul></ul><ul><li>Data Design – (Project 3) </li></ul><ul><ul><li>WHAT data will be maintained by the system </li></ul></ul><ul><ul><li>Data Model (Entity Relationship Diagram) </li></ul></ul><ul><li>User Interface Design – (Projects 4, 5, and more) </li></ul><ul><ul><li>HOW the user will work with the system </li></ul></ul><ul><ul><li>Input - Screen layouts and forms, editing, sequence, interface format, etc. </li></ul></ul><ul><ul><li>Output - Reports, queries, etc. </li></ul></ul><ul><ul><li>Prototype </li></ul></ul>

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