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SECTION 11.1

SECTION 11.1. DEVELOPING ENTERPRISE APPLICATIONS. DEVLOPING SOFTWARE. Software that is built correctly can transform as the organization and its business transforms Software that effectively meets employee needs will help an organization become more productive and enhance decision making

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SECTION 11.1

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  1. SECTION 11.1 DEVELOPING ENTERPRISE APPLICATIONS

  2. DEVLOPING SOFTWARE • Software that is built correctly can transform as the organization and its business transforms • Software that effectively meets employee needs will help an organization become more productive and enhance decision making • Software that does not meet employee needs may have a damaging effect on productivity and can even cause a business to fail

  3. DEVELOPING SOFTWARE • As organizations’ reliance on software grows, so do the business-related consequences of software successes and failures including: • Increase or decrease revenue • Repair or damage to brand reputation • Prevent or incur liabilities • Increase or decrease productivity

  4. THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC) • Systems development life cycle (SDLC) – the overall process for developing information systems from planning and analysis through implementation and maintenance

  5. THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC) • Planning phase – involves establishing a high-level plan of the intended project and determining project goals • Analysis phase – involves analyzing end-user business requirements and refining project goals into defined functions and operations of the intended system • Business requirement – detailed set of business requests that the system must meet in order to be successful

  6. THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)) • Design phase – involves describing the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentation • Development phase – involves taking all of the detailed design documents from the design phase and transforming them into the actual system

  7. THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC) • Testing phase – involves bringing all the project pieces together into a special testing environment to test for errors, bugs, and interoperability and verify that the system meets all of the business requirements defined in the analysis phase • Implementation phase – involves placing the system into production so users can begin to perform actual business operations with the system

  8. THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC) • Maintenance phase – involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goals

  9. SOFTWARE DEVELOPMENT METHODOLOGIES • There are a number of different software development methodologies including: • Waterfall • Rapid application development (RAD) • Extreme programming • Agile

  10. Waterfall Methodology • Waterfall methodology – a sequential, activity-based process in which each phase in the SDLC is performed sequentially from planning through implementation and maintenance

  11. Rapid Application Development Methodology (RAD)

  12. Extreme Programming Methodology • Extreme programming (XP) methodology – breaks a project into tiny phases, and developers cannot continue on to the next phase until the first phase is complete

  13. Agile Methodology • Agile methodology – a form of XP, aims for customer satisfaction through early and continuous delivery of useful software components • Agile is similar to XP but with less focus on team coding and more on limiting project scope • An agile project sets a minimum number of requirements and turns them into a deliverable product

  14. DEVELOPING SUCCESSFUL SOFTWARE • Primary principles for successful agile software development include: • Slash the budget • If it doesn’t work, kill it • Keep requirements to a minimum • Test and deliver frequently • Assign non-IT executives to software projects

  15. SECTION 11.2 THE SYSTEMS DEVELOPMENT LIFE CYCLE (SDLC)

  16. SDLC • Large, complex IT systems take teams of architects, analysts, developers, testers, and users many years to create • The systems development life cycle is the foundation for many systems development methodologies such as RAD and agile • Systems development life cycle – the overall process for developing information systems from planning and analysis through implementation and maintenance

  17. SDLC

  18. PHASE 1: PLANNING • Planning phase – involves establishing a high-level plan of the intended project and determining project goals • Primary planning activities include • Identify and select the system for development • Assess project feasibility • Develop the project plan

  19. Identify and Select the System for Development • Organizations use different forms of evaluation criteria to determine which systems to develop • Critical success factor (CSF) – a factor that is critical to an organization’s success

  20. Assess Project Feasibility • Feasibility study – determines if the proposed solution is feasible and achievable from a financial, technical, and organizational standpoint • Different types of feasibility studies • Economic feasibility study • Operational feasibility study • Technical feasibility study • Schedule feasibility study • Legal and contractual feasibility study

  21. Develop the Project Plan • Developing the project plan is a difficult and important activity • The project plan is the guiding force behind on-time delivery of a complete and successful system • Continuous updating of the project plan must be performed during every subsequent phase during the SDLC

  22. PHASE 2: ANALYSIS • Analysis phase – involves analyzing end-user business requirements and refining project goals into defined functions and operations of the intended system • Primary analysis activities include: • Gather business requirements • Create process diagrams • Perform a buy vs. build analysis

  23. Gather Business Requirements • Business requirements – the detailed set of business requests that the system must meet in order to be successful • Different ways to gather business requirements • Joint application development (JAD) session – where employees meet to define or review the business requirements for the system • Interviews • Questionnaires • Observations • Review business documents

  24. Gather Business Requirements • The system users review the requirements definition document and determine if they will sign-off on the business requirements • Requirements definition document – contains the final set of business requirements, prioritized in order of business importance • Sign-off – the system users’ actual signatures indicating they approve all of the business requirements

  25. Create Process Diagrams • Process modeling – graphically representing the processes that capture, manipulate, store, and distribute information between a system and its environment • Common process modeling diagrams include • Data flow diagram (DFD) – illustrates the movement of information between external entities and the processes and data stores within the system • Computer-aided software engineering (CASE) tools –automate systems analysis, design, and development

  26. Create Process Diagrams • Sample data flow diagram

  27. Perform a Buy vs. Build Analysis • An organization faces two primary choices when deciding to develop an information system • Buy the information system from a vendor • Commercial off-the shelf (COTS) – software package or solution that is purchased to support one or more business functions and information systems • SCM, CRM, and ERP solutions are typically COTS • Build the information system itself

  28. Perform a Buy vs. Build Analysis • Organizations must consider the following when making a buy vs. build decision: • Are there any currently available products that fit the needs? • Are there features that are not available and important enough to warrant the expense of in-house development? • Can the organization customize or modify an existing COTS to fit its needs? • Is there a justification to purchase or develop based on the acquisition cost?

  29. Perform a Buy vs. Build Analysis • Three key factors an organization should also consider when contemplating the buy vs. build decision • Time to market • Availability of corporate resources • Corporate core competencies

  30. PHASE 3: DESIGN • Design phase – involves describing the desired features and operations of the system including screen layouts, business rules, process diagrams, pseudo code, and other documentation • Primary design activities include: • Design the IT infrastructure • Design system models

  31. Design the IT Infrastructure • Sample IT infrastructure

  32. Design System Models • Sample entity relationship diagram (ERD)

  33. PHASE 4: DEVELOPMENT • Development phase – involves taking all of the detailed design documents from the design phase and transforming them into the actual system • Primary development activities include: • Develop the IT infrastructure • Develop the database and programs

  34. PHASE 5: TESTING • Testing phase – involves bringing all the project pieces together into a special testing environment to test for errors, bugs, and interoperability, in order to verify that the system meets all the business requirements defined in the analysis phase • Primary testing activities include: • Write the test conditions • Perform the system testing

  35. Write the Test Conditions • Test condition – the detailed steps the system must perform along with the expected results of each step

  36. PHASE 6: IMPLEMENTATION • Implementation phase – involves placing the system into production so users can begin to perform actual business operations with the system • Primary implementation activities include: • Write detailed user documentation • Determine implementation method • Provide training for the system users

  37. Write Detailed User Documentation • System users require user documentation that highlights how to use the system • User documentation – highlights how to use the system

  38. Determine Implementation Method • Four primary implementation methods • Parallel implementation • Plunge implementation • Pilot implementation • Phased implementation

  39. Provide Training for the System Users • Organizations must provide training for system users • Two most popular types of training include: • Online training – runs over the Internet or off a CD-ROM • Workshop training – set in a classroom-type environment and led by an instructor

  40. PHASE 7: MAINTENANCE • Maintenance phase – involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goals • Primary maintenance activities include: • Build a help desk to support the system users • Perform system maintenance • Provide an environment to support system changes

  41. Build a Help Desk to Support the System Users • Internal system users have a phone number for the help desk they call whenever they have issues or questions about the system • Help desk – a group of people who respond to internal system user questions • Providing a help desk is an excellent way to provide comprehensive support for new system users

  42. SOFTWARE PROBLEMS ARE BUSINESS PROBLEMS • Primary reasons for project failure include • Unclear or missing business requirements • Skipping SDLC phases • Failure to manage project scope • Scope creep – occurs when the scope increases • Feature creep – occurs when extra features are added • Failure to manage project plan • Changing technology

  43. SOFTWARE PROBLEMS ARE BUSINESS PROBLEMS • Find errors early: the later in the SDLC an error is found - the more expensive it is to fix

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