10 acquiring is post

8/2/2019 10 Acquiring is Post

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PPT Slides by Dr. Craig Tyran & Kraig Pencil

Acquiring Information Systems

MIS 320

Kraig Pencil

Fall 2010


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Game Plan

IS Acquisition

Systems Development Lifecycle (SDLC)

Modify the SDLC?

Supplemental Method: Prototyping

Alternative Method: RUP


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A. How May an IS be Acquired?1. Four common approaches BUY

1. Purchase an existing application off the shelf E.g., Turn-key application

May involve customization

1. Lease an IS application

BUILD

3. Develop in-house

4. Outsource development

E.g., software company, consulting firm


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A. How May an IS be Acquired?Acquisition approach depends on

Degree to which the needed IS application matches anexisting package available for purchase

Costs/time associated with customizing/generating IS Size of business small businesses may not be

able to afford to build customized systems Potential impact of IS

Will costs to customize/generate be worthwhile?


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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)


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Some Roles in IS Acquisition

Expert User

Client (manager)

Business Analyst

Project Manager

Executive SponsorSteering Committee

Programmer/Coder

IT manager (CIO, director, supervisor)

Designer (application/database/network, etc.)

Quality Assurance Analyst

and so on


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Development Methods

Some BUILD Options

Cowboy Coding

Waterfall method: SystemsDevelopment Life Cycle

Iterative methods:

Prototyping,

Rapid Application Development,

XP


8/17PPT Slides by Dr. Craig Tyran & Kraig Pencil

B. Systems Development Lifecycle

1. 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



Systems Development Life Cycle(Note: Eight-phase model of textbook has been condensed to a five-phase model)

Systems

Investigation

Analysis

Design

Programming &

Testing &

Implementation

Operation &

Maintenance

What should the

system do ?

How to

build thes s em ?

Build the

system !

Business &

Interpersonal

Skills

Technical

Skills

ProjectManagement

Skills



B. Systems Development Lifecycle

(cont.)2. How much computer

programming is done by

the end of the Analysis phase?

Why?

3. 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



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



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



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



D. Supplemental Method: Prototyping

1. Prototyping Develop a working model of a system

MS Excel and MS Access can be used forprototyping 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



Preliminary Analysis:

Understand the basic user

requirements to help

develop the initial prototype After the PreliminaryAnalysis, the developer

creates a system for initial

review by user(s).

User(s) test system

and provide

feedback.

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

Prototyping

Figure from Haag, et al (2004)



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 easiertechnology (e.g. Access) as proof of

concept for a more complex technology (e.g. Oracledatabase)

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


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E. Example of an Alternative Method to SDLC:

Rational Unified Process

Image source:

http://upload.wikimedia.org/wikipedia/en/a/aa/RationalUnifi

Iterations

Within

Phases
http://upload.wikimedia.org/wikipedia/en/a/aa/RationalUnifiedProcess.pnghttp://upload.wikimedia.org/wikipedia/en/a/aa/RationalUnifiedProcess.png

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