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Game Plan. IS AcquisitionSystems Development Lifecycle (SDLC)Modify the SDLC?Supplemental Method: PrototypingAlternative Method: RUP. A. How May an IS be Acquired?. Four common approachesBUYPurchase an existing application
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1. Acquiring Information Systems MIS 320
Kraig Pencil
Fall 2010
3. A. How May an IS be Acquired? Four common approaches
BUY
Purchase an existing application off the shelf
E.g., Turn-key application
May involve customization
Lease an IS application
BUILD
Develop in-house
Outsource development
E.g., software company, consulting firm
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?
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 (leased) over the Internet
SalesForce.com ? worlds 4th fastest growing company (Fortune Magzine)
6. 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
7. Development Methods Some BUILD Options
Cowboy Coding
Waterfall method: Systems Development Life Cycle
Iterative methods: Prototyping, Rapid Application Development, XP
8. 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
10. 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
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 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. 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. 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
Dont need to discard the prototype
May speed up development process
Flexible
Disadvantage: may never be complete