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Acquiring Information Systems

Acquiring Information Systems. MIS 320 Kraig Pencil Summer 2013. Game Plan. IS Acquisition Systems Development Lifecycle (SDLC) Modify the SDLC? Supplemental Method: Prototyping Alternative Method: RUP.

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Acquiring Information Systems

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  1. Acquiring Information Systems MIS 320 Kraig Pencil Summer 2013

  2. Game Plan • IS Acquisition • Systems Development Lifecycle (SDLC) • Modify the SDLC? • Supplemental Method: Prototyping • Alternative Method: RUP

  3. A. How May an IS be Acquired? For example: acquiring software applications

  4. A. How May an IS be Acquired? Acquisition approach depends on … • Degree to which the needed IS application matches an existing package available for purchase • Costs/time associated with customizing/generating IS • Size of business – small businesses may not beable to afford to build customized systems • Potential impact of IS • Will costs to customize/generate be worthwhile? • Is the system “mission critical”?

  5. A. How May an IS be Acquired? Some BUY Options Some Commonly Purchased /Leased Packages • Email and productivity packages: • Microsoft Office and Outlook • Google Apps • Accounting • CRM (Customer Relationship Management) • ERP systems The “Cloud” option • Systems provided (“subscribed to”) over the Internet • SalesForce.com  world’s 4thfastest growing company (Fortune Magzine)

  6. Development Methods Some BUILD Options • Cowboy Coding • Waterfall method: Systems Development Life Cycle • Iterative methods: Prototyping, Rapid Application Development, XP

  7. B. Systems Development Lifecycle • Traditional Systems Development Life Cycle (SDLC) • A series of development stages • “Waterfall” type of model • Complete one stage and then move onto the next stage • Development process flows “downstream” • One example of a SDLC … • See figure on next slide

  8. Systems Development Life Cycle (Note: Eight-phase model of textbook has been condensed to a five-phase model) Business & Interpersonal Skills Systems Investigation What should the system do ? Operation & Maintenance Analysis Technical Skills Project Management Skills Programming &Testing &Implementation Design Build the system ! How to build the system ?

  9. B. Systems Development Lifecycle (cont.) • How much computer programming is done by the end of the Analysis phase? • Why? • What does a “systems analyst” (or “business analyst”) do? • Understand what a proposed IS is supposed to do  IS solution Top image source: http://www.thecolor.com/images/Computer-Programmer.gif

  10. Some Roles in IS Acquisition Expert User Client (manager) Business Analyst Project Manager Executive Sponsor Steering Committee Programmer/Coder IT manager (CIO, director, supervisor) Designer (application/database/network, etc.) Quality Assurance Analyst … and so on

  11. Showcase: The Business Analyst Someone in the IT department whose job is … • … talking with managers about their business needs (problems), • … organizing teams of IT specialists and business experts • … developing project plans and budget estimates • … leading* the selection (purchase) or development of systems that satisfy managers’ IT needs/problems*continued monitoring, communicating, guiding, cheerleading …

  12. C. Modify the SDLC ? 1. A key assumption underlying the traditional SDLC • The specific answers to the “What should the system do?” question can be established by the end of Analysis stage 2. Is this an appropriate assumption for all types of systems? Consider two types of IS: • TPS: Performs routine, repetitive tasks • DSS: • Supports non-routine decisions, Un/Semi-structured decisions • Users are uncertain of system requirements 3. What are the implications for IS development? • A modified development approach that involves iterations can be useful

  13. C. Modify the SDLC ? 4. Need to help developers – and users – to better understand system requirements for DSS applications  Incorporate “prototyping” and/or iterations into development process

  14. Prototyping

  15. D. Supplemental Method: Prototyping 1. Prototyping • Develop a “working model” of a system • MS Excel and MS Access can be used for prototyping … and final system development • Let users work with prototype  Get feedback • Advantages • Discover /clarify the users’ “system requirements” • Flexible development approach • Active user involvement • Test system interface • Can use a small prototype as the “proof of concept” for a large final system

  16. Prototyping Preliminary Analysis: Understand the basic user requirements to help develop the initial prototype After the Preliminary Analysis, the developer creates a system for initial review by user(s). Based on feedback, system will be revised and tested again User(s) test system and provide feedback. Eventually the prototype gets a “thumbs up”. Some prototypes are “throwaways” and others are “evolutionary prototypes” Figure from Haag, et al (2004)

  17. D. Supplemental Method: Prototyping 2. Types of prototypes • Throwaway prototype • Used for demo purposes … “quick and dirty” prototype • Can help determine requirements more quickly • Construct final system after the throwaway(s) • Can use an easier technology (e.g. Access) as “proof of concept” for a more complex technology (e.g. Oracle database) • Evolutionary prototype • Prototype is continually refined until final system is built • Advantages for DSS • Don’t need to discard the prototype • May speed up development process • Flexible • Disadvantage: may never be “complete”

  18. E. Example of an Alternative Method to SDLC: “Rational Unified Process” Iterations Within Phases Image source: http://upload.wikimedia.org/wikipedia/en/a/aa/RationalUnifiedProcess.png

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