Chapter Extension 17

Small-Scale Systems Development

© 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

CE17-2 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Study Questions

How does systems development vary according to project scale?

What is a typical small-scale project? How does the systems definition phase apply to BBB? How does the requirements definition phase apply to

BBB? How do design and implementation phases apply to

BBB? How does the maintenance definition phase apply to

BBB? What can you learn from the BBB case?

CE17-3 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Systems Development Life Cycle

SDLC– Can be applied to projects of any scale

Nature and characteristics of work vary

Small-scale projects vary from large-scale projects– Different tasks required

CE17-4 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Small-Scale Projects

Simple requirements Involve few business processes Seldom have IT support

– May use consultants Frequently only part-time basis

Often short in duration Staff may be inexperienced

CE17-5 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Small-Scale Projects, continued

Usually limited budget– May be unrealistically limited– Due to being naive

Informal and loose– Fewer users

System supported by users Little attention may be paid to:

– Security– Backup– Recovery

CE17-6 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Large-Scale Projects

Involve many different business processes Uses IT professionals project managers, systems analysts, network

administrators, programmers, database designers, PQA professionals, trainers

May require a year or more to complete Budgets sizeable

– May still be inadequate

CE17-7 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Large-Scale Projects, continued

Staff usually experienced System supported by professionals Normally secured Backup and recovery systems in place

CE17-8 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

System Development Characteristics

Figure CE 17-1

CE17-9 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

What Is a Typical Small-Scale Project?

BBB is an example of a small-scale project– Resorts want to share data about their properties

Each resort could develop own database– Share information over Internet

Resorts could develop centralized database

– Need systems development process Assist in development

– May need custom applications Assess progress Maintain system

CE17-10 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

How Does the Systems Definition Phase Apply to BBB?

BBB must define their needs and goals:– What does sharing property mean?– How elaborate a system is needed?– What properties are to be shared?– How will compensation be computed?

Feasibility needs to be assessed:– Schedule– Technology– Cost

Alternatives must be explored Project must be planned

CE17-11 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Systems Definition for BBB

Figure CE 17-2

CE17-12 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

How Does the Requirements Phase Apply to BBB?

Tasks will depend on type of system development– Not much needs to be done for email exchanges– Considerable work will need to be done if they will share

Web-accessible database– Define the user roles:

Access listings to rent Add/update/remove listings

– Review current rental procedures– Create prototypes of forms

CE17-13 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Technological Requirements

Other considerations:– Are application programs required?– What features need to be included?– What secure access will be used?

Procedures for revoking access

– Five components of information system

CE17-14 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

How Do Design and Implementation Phases Apply to BBB?

BBB will probably need outside consultant– Much consider each of five components of information system

BBB needs to identify hardware to host website Needs Web server software

– Consider off-the-shelf– Buy vs. build

Define users:– Property-listing users– Property-listing updaters– System administrators

CE17-15 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Implementation Phase

Determine needs Training Use of system Conversion Maintenance Backup and recovery

CE17-16 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Requirements Analysis for BBB

Figure CE17-3

CE17-17 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Aim for What You Want

Focus on what you want and where you want to go– Know what you want– If you don’t know, focus on what you can do

Focus on the systems requirements– Know what you want to build– Manage the requirements

Build incrementally if necessary

Put your attention where you want to go

CE17-18 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

How Does the Maintenance Phase Apply to BBB?

Maintenance– Fix the system

Specify acceptable level of performance Control system quality

– Adapt the system System is just a first step May be expanded May be discontinued

CE17-19 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

What Can You Learn from the BBB Case?

You can learn how to proceed– Who to hire

Use SDLC as a guide– Identify the system– Investigate feasibility– Specify requirements– Design– Implement – Modify

Accomplish goals and objectives

CE17-20 © 2008 Pearson Prentice Hall, Experiencing MIS, David Kroenke

Active Review

How does systems development vary according to project scale?

What is a typical small-scale project? How does the systems definition phase apply to BBB? How does the requirements definition phase apply to

BBB? How do design and implementation phases apply to

BBB? How does the maintenance definition phase apply to

BBB? What can you learn from the BBB case?