Systems Development

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Chapter 12
Systems Development
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Overview of Systems Development

• Participants
• Initiating systems development
• Information systems planning
• Establishing objectives for systems development
• Systems development and the Internet
• Trends in systems development and enterprise
  resource planning

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Participants

• Stakeholders
• Individuals/organizations who are beneficiaries
  of the systems development effort
• Systems analyst
• Professional who specializes in analyzing and
  designing business systems
• Users
• Individuals who interact with the system
  regularly
• Programmer
• Individual responsible for modifying or
  developing programs to satisfy user requirements

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Managers
System stakeholders
Programmers
Systems analyst
Users
Technicalspecialists
Vendors and suppliers
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Systems Analyst
A programmer or consultant who designs and
manages the development of business
applications. Typically, systems analysts are
more involved in design issues than in
day-to-day coding. However, systems analyst is a
somewhat arbitrary title, so different companies
define the role differently.
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Typical Reasons to Initiate a Systems Development
Project
Problems with existing systems
Desire to exploit new opportunities
Increasing competition
Perception of potential benefit by
individualcapable of initiatingchange
Systems developmentprocess initiated
Desire to make moreeffective use of information
Organizational growth
Merger or acquisition
Change in market orexternal environment
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Planning

• Information systems planning
• The translation of strategic and organizational
  goals into systems development initiatives
• Creative analysis
• The investigation of new approaches to existing
  problems
• Critical Analysis
• The unbiased and careful questioning of whether
  system elements are related in the most effective
  or efficient ways

Strategic plan
IS planning
Systems developmentinitiatives
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Steps in IS Planning
Strategic plan
Previously unplannedsystem projects
Developing overall objectives
Identify IS projects
Set priorities select projects
Analyse resource requirements
Set schedules and deadlines
Develop IS planning document
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Establishing Objectives for Systems Development

• Performance objectives
• Quality or usefulness of the output
• The quality or usefulness of the format of the
  output
• The speed at which the output is generated
• Cost objectives
• Development costs
• Costs related to the uniqueness of the system
  application
• Fixed investments in hardware and related
  equipment
• On-going operating costs of the system

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Systems Developmentand the Internet

• Applications being moved to the Internet
• Sales
• Order placement
• Product information access
• Building a static Web site
• Intranet tools
• NetDynamics
• SilverStream
• Web-Logic
• Novera
• Netscape Communications

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Systems Development Life Cycle

• Systems investigation
• Problems and opportunities are identified
• Systems analysis
• Existing systems and work processes are studied
• Systems design
• Defines how the information system will do what
  it must do to solve the problem
• Systems implementation
• System components are assembled and the new or
  modified system is placed into operation
• Systems maintenance and review
• Ensures the system operates and is modified to
  keep up with business changes

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Systems investigation(understand problem)
Systems Analysis(understand solution)
Systems design(select and plan best solution)
Systems implementation(place solution into
effect)
Systems maintenanceand review(evaluate results
of solution)
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Cost tomake a particularchange
Investigation Analysis Design Implementation Maint
enance and review
Time
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Prototyping

• Operational prototype
• Accesses real data files, edits input data, makes
  necessary computations and comparisons, and
  produces real output
• Non-operational prototype
• A mockup or model that includes output and input
  specifications and formats
• Rapid application development (RAD)
• Employs tools, techniques, and methodologies
  designed to speed application development,
  automates source code generation, and facilitates
  user involvement in design and development
  activities
• Joint application development (JAD)
• Involves group meetings in which users,
  stakeholders, and IS professionals work together
  to analyze existing systems, proposed solutions,
  and define requirements for a new or modified
  system.

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Rapid Application Development
A programming system that enables programmers to
quickly build working programs. In general, RAD
systems provide a number of tools to help build
graphical user interfaces that would normally
take a large development effort. Two of the most
popular RAD systems for Windows are Visual Basic
and Delphi. Historically, RAD systems have
tended to emphasize reducing development time,
sometimes at the expense of generating efficient
executable code. Nowadays, though, many RAD
systems produce extremely fast code. Conversely,
many traditional programming environments now
come with a number of visual tools to aid
development. Therefore, the line between RAD
systems and other development environments has
become blurred.
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Prototyping The Iterative Life Cycle
Iteration 1
Iteration 2
Iteration 3 (final)
Determinerequirements
Determinerequirements
Determinerequirements
Analysealternatives
Analysealternatives
Analysealternatives
Specify design
Specify design
Specify design
Implementdesign
Implementdesign
Implementdesign
User review
User review
Changeover
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General Model of Prototyping
Systems development initiated
Investigate and analyse problemsufficiently to
developworkable solution
Develop prototype
Put prototype into operation
Refine and modify prototype
Complete component or system
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End-User Systems Development Life Cycle

• End-user systems development life cycle
• Any systems development project in which the
  primary effort is undertaken by a combination of
  business managers and users

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Factors Affecting Systems Development Success

• Managing change
• Requires the ability to recognize existing or
  potential problems and deal with them before they
  become a serious threat to the success of a new
  or modified system
• Use of project management tools
• Schedule
• Milestone
• Deadline
• Critical path
• Program Evaluation Review Technique (PERT)
• Gantt chart

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Selected Project Management Software Packages
Software Vendor
BeachBox 98 NetSQL Partners
Job Order Management Software Inc.
OpenPlan Welcom
Project Microsoft
Project Scheduler Scitor Corp.
Super Project Computer Associates
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Use of Computer-Aided Software Engineering (CASE)
Tools

• CASE tools automate tasks required in a system
  development effort and enforces adherence to the
  SDLC
• Upper CASE tools
• Tools that focus on activities associated with
  the early stages of systems development
• Lower CASE tools
• Tools that focus on the later implementation
  stage of systems development
• Integrated-CASE (I-CASE) tools
• Tools that provide links between upper- and
  lower-CASE packages, allowing lower-CASE packages
  to generate program code from upper-CASE package
  generated designs

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CASE

• Short for Computer Aided Software Engineering, a
  category of software that provides a development
  environment for programming teams. CASE systems
  offer tools to automate, manage and simplify the
  development process. These can include tools for
  
• Summarizing initial requirements
• Developing flow diagrams
• Scheduling development tasks
• Preparing documentation
• Controlling software versions
• Developing program code
• Various companies offer CASE software capable of
  supporting some or all of these activities. While
  many CASE systems provide special support for
  object-oriented programming, the term CASE can
  apply to any type of software evelopment
  environment.

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ISO 9000

• An international standard used by IS departments
  to ensure quality standards exist and are
  maintained in their products and services

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Systems Investigation

• Identify potential problems and opportunities and
  consider them in light of the goals of the
  company
• The investigation team
• Managers and stakeholders
• IS personnel
• Task
• Undertake feasibility analysis
• Establish system development goals
• Select system development methodology
• Prepare system development report

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Feasibility Analysis

• Technical feasibility
• Can the hardware, software, and other system
  components be acquired or developed to solve the
  problem?
• Operational feasibility
• Can the project be put into action or operation?
• Schedule feasibility
• Can the project be completed in a reasonable
  amount of time?
• Economic feasibility
• Does the project make financial sense?
• Net present value
• The preferred approach for ranking competing
  projects and determining economic feasibility

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The Systems Investigation Report

• A report that summarizes the results of the
  systems investigation and the process of
  feasibility analysis and recommends a course of
  action
• Steering committee
• An advisory group consisting of senior management
  and users from the IS department and other
  functional areas

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Systems Analysis

• Typical table of contents from a systems
  investigations report

• Table of Contents
• Executive summary
• Review of goals and objectives
• System problems and opportunities
• Project feasibility
• Project costs
• Projects benefits
• Recommendations

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Sources of Data

• Internal Sources
• Users, stakeholders, managers
• Organization charts
• Forms and documents
• Procedure manuals and policies
• Financial reports
• IS manuals
• Other measures of business processes

• External Sources
• Customers
• Suppliers
• Stockholders
• Government agencies
• Competitors
• Outside groups
• Journals, etc.
• Consultants

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Data Collection

• Structured Interview
• Unstructured Interview
• Direct Observation
• Questionnaires
• Statistical Sampling

Identify data sources
Data collection
Follow-up clarification
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Data Analysis

• Data analysis
• Manipulating collected data so that it is usable
  for the development team members participating in
  systems analysis
• Data modeling
• A commonly accepted approach to modeling
  organizational objects and associations that
  employ both text and graphics
• E.g, ER (entity relationship) diagrams
• Activity modeling
• A method to describe related objects,
  associations, and activities
• Data flow diagram
• A diagram that models objects, associations, and
  activities by describing how data can flow
  between and around them

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ER Example
MID
Play
1
?
Game of Golf
Member
Name
Address
Datepaid
Date
Time
Score
MID
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Data Flow Diagram

• Schematic description of business processes
• Premise for every activity there is some
  communication, transference, for flow that can be
  described as a data element
• DFDs show logical sequences (not physical
  processes)

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Processsymbol
Entity symbol
Data-flow line
Data-flow line
Data store
Assign Tee time
Tee time
Available times
Member
Schedule
Reservation request
Group information
Membertee time
Course access
Checkmemberin
Member
Member card
Member ID
Date
Sortscores
Score card
Score card
Member
Scores
Calculatehandicap
Handicap
Tee time
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Application Flowchart

• Charts that show relationships among applications
  or systems

Order processingapplication
Inventory controlapplication
Invoicingapplication
Marketing analysisapplication
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Grid Charts

• A table that shows relationships among the
  various aspects of a systems development effort

Databaseapplications Customerdatabase Inventorydatabase Supplierdatabase Accounts receivabledatabase
Order processingapplications
Inventory controlapplication
Marketing analysisapplication
Invoicingapplication
X
X
X
X
X
X
X
X
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Requirements Analysis

• An assessment used to determine user,
  stakeholder, and organizational needs

Strategytranslation
Goals and missionof the organization
Systemsrequirements
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Screen Layout Charts

• May be tailored for
• Frequent users who require little descriptive
  information, or
• Infrequent users who require more descriptive
  information

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For frequent users
ORDER ENTRY ORDER ENTRY ORDER ENTRY ORDER ENTRY ORDER ENTRY ORDER ENTRY
ORDER NO. CUSTOMER NO. SALES PERSON REGION COMMISSION NET DOLLARS
XXXXX XXXXX XXXXX XXX XXX XXXXX

ITEM NO. QTY UNIT PRICE DOLLARS DISCOUNTS
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
XXXXXXX XXXX XX XXXXX XXXXXX XX XX XX
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For infrequent users
Which online option would you like to
perform? (Please enter an X to make a
selection) _DATA ENTRY Enter transaction and
report requests for later
processing _RETRIEVALS Review online
information from the database bill of
materials, where-used, routing, item data
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The Systems Analysis Report

• Strength and weaknesses of existing system from a
  stakeholders perspective
• User/stakeholder requirements for the new system
• Organizational requirements
• Description of what new information systems
  should do to solve the problem

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Typical Table of Contents for a Report on an
Existing System
Johnson Flores, Inc. Systems Analysis Report
TABLE OF CONTENTS Background Information Problem
or Need Statement Data Collection Data and
Requirements Analysis Recommendations Appendixes
of Documents, Tables, and Charts Glossary of
Terms
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End of Chapter 12
Chapter 13