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Systems Development

Systems Development. Why is Packaged Software Sometimes Not Enough? Chapter 12. Student Learning Outcomes. Discuss why organizations develop computer systems List the six phases within the systems development life cycle (SDLC) and describe the major purposes of each

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Systems Development

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  1. Systems Development Why is Packaged Software Sometimes Not Enough? Chapter 12

  2. Student Learning Outcomes • Discuss why organizations develop computer systems • List the six phases within the systems development life cycle (SDLC) and describe the major purposes of each • Define the people who are included on most project development teams ©2003 The McGraw-Hill Companies

  3. Student Learning Outcomes • Describe the reasons why modeling systems from both a logical and physical perspective is important • Define end user development and how it differs from the traditional systems development life cycle (SDLC) and the advantages and disadvantages of end user development • Describe why organizations choose to outsource systems development and the major steps in outsourcing ©2003 The McGraw-Hill Companies

  4. Student Learning Outcomes • Define end user development and how it differs from the traditional systems development life cycle (SDLC) and the advantages and disadvantages of end user development • Describe why organizations choose to outsource systems development and the major steps in outsourcing ©2003 The McGraw-Hill Companies

  5. Introduction Organizations today are very dependent on computer systems. To develop successful computer systems requires great skill and knowledge. Most people will not be involved in actually developing systems from scratch but they will certainly be using them. ©2003 The McGraw-Hill Companies

  6. 12.1 Why Organizations Develop Systems Become more efficient Level the competitive playing field Achieve an advantage through innovation ©2003 The McGraw-Hill Companies

  7. Developing Systems to Become More Efficient • Some organizations develop systems just to be more efficient in their internal processes • New system may not be designed to yield a market advantage but to add to the survivability and the bottom line of an organization by making it more productive ©2003 The McGraw-Hill Companies

  8. Developing Systems to Level the Competitive Playing Field • Developing new systems to stay competitive in the marketplace is often a “reactionary” measure • Example: UPS and the U.S. Postal System developed a tracking system similar to FedEx p.12.359 Fig. 12.1 ©2003 The McGraw-Hill Companies

  9. Developing a System to Achieve an Advantage Through Innovation FedEx developed its new customer-oriented parcel tracking software to achieve an advantage over its competitors. Results 1. Until UPS and others were able to develop similar systems FedEx attracted many new customers (away from its competition). 2. FedEx was also able to reduce the number of people handling incoming phone calls for parcel pickup and tracking. ©2003 The McGraw-Hill Companies

  10. Example of Achieving Advantage Through Innovation • Self-scanning systems at the grocery store helped to achieve a competitive advantage • People can get through the checkout process quickly ©2003 The McGraw-Hill Companies

  11. 12.2 The Traditional Systems Development Life Cycle p.12.360 Fig. 12.2 ©2003 The McGraw-Hill Companies

  12. Why Your Participation is Important in the SDLC • You are or will be a: • Business process expert • Quality control analyst • Manager of other people • Your participation is important ©2003 The McGraw-Hill Companies

  13. Richmond Blood CenterCurrent System 2 1 4 3 p.12.361 Fig. 12.3 ©2003 The McGraw-Hill Companies

  14. First Phase of the SDLC - Systems Investigation Four tasks: 1. Define the Problem/Opportunity 2. Assess Initial Feasibility 3. Build the Project Team 4. Create A Systems Development Project Plan • SimNet Concepts Support CD: “Systems Development Overview” ©2003 The McGraw-Hill Companies

  15. Systems Investigation p.12.362 Fig. 12.4 ©2003 The McGraw-Hill Companies

  16. Initial Feasibility Assessment Time feasibility assessment Technical feasibility assessment Fiscal feasibility assessment ©2003 The McGraw-Hill Companies

  17. Composition of Systems Development: Project Teams System Champion Programmer(s) Several Users Hardware Specialist(s) Systems Analyst(s) Project Manager ©2003 The McGraw-Hill Companies

  18. Elements of a Systems Development Project Plan p.12.363 Fig. 12.5 ©2003 The McGraw-Hill Companies

  19. Project Management Software • Most project teams use project management software such as Microsoft Project to help them effectively manage the project plan and organize all of the documents associated with the development of a specific project • SimNet Concepts Support CD: “Project Management Applications” ©2003 The McGraw-Hill Companies

  20. Systems Analysis p.12.364 Fig. 12.6 ©2003 The McGraw-Hill Companies

  21. Systems Analysis Phase • Model how the current system works from a logical point of view • Identify current system weaknesses and the opportunities to improve • Create a logical model of the new system • Review the project plan ©2003 The McGraw-Hill Companies

  22. Richmond Blood Center Data Flow Diagram (DFD) p.12.365 Fig. 12.7 ©2003 The McGraw-Hill Companies

  23. Systems Design p.12.366 Fig. 12.8 ©2003 The McGraw-Hill Companies

  24. Systems Design Phase • Generate several alternative technical solutions for the new logical model • Select the best technical alternative • Develop detailed software specifications • Review the project plan ©2003 The McGraw-Hill Companies

  25. Richmond Blood CenterFlowchart p.12.367 Fig. 12.9 ©2003 The McGraw-Hill Companies

  26. Intranet Protected by a FirewallRichmond Blood Center ©2003 The McGraw-Hill Companies

  27. Systems Construction p.12.368 Fig. 12.10 ©2003 The McGraw-Hill Companies

  28. Systems Construction Phase • Acquire and installing new hardware • Write software • Test the software • Review the project plan • Note: 80 to 90 percent of all efforts are devoted to this phase ©2003 The McGraw-Hill Companies

  29. Systems Implementation p.12.369 Fig. 12.11 ©2003 The McGraw-Hill Companies

  30. Systems Implementation Phase • Convert existing information to the new system • Convert users • Perform Acceptance testing • Review the project plan ©2003 The McGraw-Hill Companies

  31. Conversion Techniques ©2003 The McGraw-Hill Companies

  32. Systems Support p.12.370 Fig. 12.12 ©2003 The McGraw-Hill Companies

  33. Systems Support Phase • Provide a formal mechanism for system review • Provide mechanism for requesting changes • Evaluate proposed system changes • Initiate system changes ©2003 The McGraw-Hill Companies

  34. Systems Support: Seek Answers Frequently to these Questions • Does this system still support the overall • business goals? 2. Do modifications need to be made to this system in light of changes to business processes? ©2003 The McGraw-Hill Companies

  35. Support Costs for a System p.12.371 Fig. 12.13 ©2003 The McGraw-Hill Companies

  36. End User Development Outsourcing SDLC 12.3 End User Development and Prototyping • Organizations develop computer systems using three different methods: ©2003 The McGraw-Hill Companies

  37. End User Development • End user development is growing in popularity • It is estimated that most organizations have a five year back-log of requests for new proposed systems • Organizations are empowering employees to develop small-scale systems themselves ©2003 The McGraw-Hill Companies

  38. Prototyping • Prototyping is the process of building a model that demonstrates the features of a proposed product, service, or system • People and organizations perform prototyping all the time i.e., • Automobile manufacturers • Building contractors • Your instructor (sample exam questions) ©2003 The McGraw-Hill Companies

  39. Prototyping: An Iterative Process 1. Identify the basic requirements of the system 2. Build a prototype from basic requirements 3. Have other users review the prototype and suggest changes 4. Refine and enhance the prototype until it’s complete ©2003 The McGraw-Hill Companies

  40. Prototyping SDLC Prototyping End User Development Prototyping p.12.373 Fig. 12.14 ©2003 The McGraw-Hill Companies

  41. End User Development Cycle p.12.374 Fig. 12.15 ©2003 The McGraw-Hill Companies

  42. Advantages of End User Development • Encourages active user participation • Improves requirements determination • Strengthens user sense of ownership • Increases speed of systems development ©2003 The McGraw-Hill Companies

  43. Disadvantages of End User Development • Inadequate expertise leads to underdeveloped systems • Lack of organizational focus creates "privatized" system • Insufficient analysis and design leads to subpar systems • Lack of documentation of a system may lead to its being short lived ©2003 The McGraw-Hill Companies

  44. 12.4 Outsourcing • Another alternative to developing a computer system • Delegation of work to a group outside of your organization for: • A specified period of time • A specified cost • A specified level of service ©2003 The McGraw-Hill Companies

  45. Ways an Organization Can Outsource • Purchasing horizontal software • Purchasing vertical market software • Hiring an outsource vendor to develop from scratch p.12.375 Fig. 12.16 ©2003 The McGraw-Hill Companies

  46. How Outsourcing Compares to SDLC • Organization turns over much of the design, construction, implementation, and support steps to another organization • Organization is still responsible for: • Investigation • Analysis • Creating a request for proposal ©2003 The McGraw-Hill Companies

  47. Outsourcing Cycle p.12.376 Fig. 12.17 ©2003 The McGraw-Hill Companies

  48. A System May be Targeted for Outsourcing When: • It is determined that the in-house IT specialists do not have enough time or resources to build a system • The organization does not possess the expertise to develop a given system • It is determined that it is cheaper to buy prewritten horizontal or vertical market software than it is to develop it from scratch ©2003 The McGraw-Hill Companies

  49. Building a Request for Proposal (RFP) • RFP is a formal document that outlines the logical requirements for the proposed system and invites outsourcing vendors to bid on its development • RFP can be long and complex, requiring months to create. Do not rush through it ©2003 The McGraw-Hill Companies

  50. RFP: Outsourcing p.12.377 Fig. 12.18 ©2003 The McGraw-Hill Companies

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