Acquiring Information Systems
MIS 320
Kraig Pencil
Summer 2013
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Game Plan
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IS Acquisition
Systems Development Lifecycle (SDLC)
Modify the SDLC?
Supplemental Method: Prototyping
Alternative Method: RUP
PPT Slides by Dr. Craig Tyran & Kraig Pencil
A. How May an IS be Acquired?
For example: acquiring software applications
“Buy” existing
application
Purchase: Off the shelf
Lease
Service
(a.k.a. “SaaS or “Cloud”)
Open Source: customize
“Build”
new application
PPT Slides by Dr. Craig Tyran & Kraig Pencil
In-house
Outsource
A. How May an IS be Acquired?
Acquisition approach depends on …
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Degree to which the needed IS application matches an
existing package available for purchase
Costs/time associated with customizing/generating IS
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Size of business – small businesses may not be
able to afford to build customized systems
Potential impact of IS
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Will costs to customize/generate be worthwhile?
Is the system “mission critical”?
PPT Slides by Dr. Craig Tyran & Kraig Pencil
A. How May an IS be Acquired?
Some BUY Options
Some Commonly Purchased /Leased Packages
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Email and productivity packages:
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Microsoft Office and Outlook
Google Apps
Accounting
CRM (Customer Relationship Management)
ERP systems
The “Cloud” option
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Systems provided (“subscribed to”)
over the Internet
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SalesForce.com  world’s 4th
fastest growing company
(Fortune Magzine)
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Development Methods
Some BUILD Options
• Cowboy Coding
• Waterfall method:
Systems Development Life Cycle
• Iterative methods:
Prototyping,
Rapid Application Development,
XP
PPT Slides by Dr. Craig Tyran & Kraig Pencil
B. Systems Development Lifecycle
1.
Traditional Systems Development
Life Cycle (SDLC)
• A series of development stages
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“Waterfall” type of model
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Complete one stage and then
move onto the next stage
Development process flows
“downstream”
One example of a SDLC …
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See figure on next slide
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Systems Development Life Cycle
(Note: Eight-phase model of textbook has been condensed to a five-phase model)
Systems
Investigation
Business &
Interpersonal
Skills
What should the
system do ?
Operation &
Technical Maintenance
Analysis
Skills
Build the
system !
Programming &
Testing &
Implementation
Project
Management
Skills
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Design
How to build
the system ?
B. Systems Development Lifecycle (cont.)
2. How much computer
programming is done by
the end of the Analysis phase?
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Why?
3. What does a “systems analyst”
(or “business analyst”) do?
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Understand what a proposed IS
is supposed to do  IS solution
Top image source: http://www.thecolor.com/images/Computer-Programmer.gif
PPT Slides by Dr. Craig Tyran & Kraig Pencil
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
PPT Slides by Dr. Craig Tyran & Kraig Pencil
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 …
PPT Slides by Dr. Craig Tyran & Kraig Pencil
C. Modify the SDLC ?
1. A key assumption underlying the traditional SDLC
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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:
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TPS: Performs routine, repetitive tasks
DSS:
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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
PPT Slides by Dr. Craig Tyran & Kraig Pencil
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
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Prototyping
PPT Slides by Dr. Craig Tyran & Kraig Pencil
D. Supplemental Method: Prototyping
1. Prototyping
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Develop a “working model” of a system
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MS Excel and MS Access can be used for
prototyping … and final system development
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Let users work with prototype
 Get feedback
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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
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Preliminary Analysis:
Understand the basic user
requirements to help
develop the initial
prototype
Prototyping
User(s) test system
and provide
feedback.
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
Eventually the prototype gets a “thumbs
up”. Some prototypes are “throwaways”
and others are “evolutionary prototypes”
Figure from Haag, et al (2004)
PPT Slides by Dr. Craig Tyran & Kraig Pencil
D. Supplemental Method: Prototyping
2. Types of prototypes
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Throwaway prototype
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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
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Prototype is continually refined until final system is built
Advantages for DSS
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Don’t need to discard the prototype
May speed up development process
Flexible
Disadvantage: may never be “complete”
PPT Slides by Dr. Craig Tyran & Kraig Pencil
E. Example of an Alternative Method to SDLC:
“Rational Unified Process”
Iterations
Within
Phases
PPT Slides by Dr. Craig Tyran & Kraig Pencil
Image source:
http://upload.wikimedia.org/wikipedia/en/a/aa/Rational
UnifiedProcess.png