TopicVII Information Systems Development

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MIS 601 : ManagementInformation Systems

Topic VII : Developing

Business/IT Solutions


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Contents

IS Development SystemsApproach

Systems DevelopmentLifecycle

Systems InvestigationSystems Analysis

Systems Design

Systems Implementation

Systems Maintenance


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Information Systems Development

When the systems approach to problemsolving is applied to the development of

IS solutions to Business problems it iscalled Information SystemsDevelopment.

The key to successful SystemsDevelopment is through Systems

Analysis & Design (SSAD)


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Information Systems Development

Systems Analysis

The process of understanding and specifying indetail what the information system should do?

Systems Design

The process of specifying in detail how manycomponent parts of the information systemshould be physically implemented.

Systems AnalystThe person who uses Analysis and Designtechniques to solve business problems using IT.


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Systems Approach to Problem Solving

Design

theSolution

Design

theSolution

UnderstandThe Problem

UnderstandThe Problem

DevelopAlternativeSolutions

DevelopAlternativeSolutions

Select

theSolution

Select

theSolution

Implementthe

Solution

Implementthe

Solution

MonitorandEvaluate

Results


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Systems Analyst

Using Systems Engineering to understanda problem or opportunity is one of the

most important task of a SystemsAnalyst:-What should it do?

What are the component parts?

How should they be configured?

What technology should be used to build the different components?

Who should build them?


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Systems Development Life Cycle

(SDLC)Using the systems approach to develop

Information System Solutions can beviewed as a multi step process called asa Systems Development Life Cycle

(SDLC)

Depending upon the products that result

from each step in the cycle, you canrecycle back to any previous step if morework is needed.


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Systems Development Life Cycle (SDLC)

There are 5 stages in this cycle :-Investigation

AnalysisDesign

ImplementationMaintenance


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Traditional Systems Development Life Cycle


Product:Operational System


Product:Operational System

Systems InvestigationProduct:

Feasibil ity Study

Systems InvestigationProduct:

Feasibili ty Study

Systems Analysis

Product:Functional Requirements

Systems Analysis

Product:Functional Requirements

Systems Design

Product:System Specif ications

Systems Design

Product:System Specifications

Systems Maintenance

Product:Improved System

Systems Maintenance

Product:Improved System

Understand theBusinessProblem orOpportunity

Develop anInformation

SystemSolution

Implementthe InformationSystemSolution


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Phase 1 : Systems Investigation

What are the Business Priorities?How can Information Technologiesprovide Information systemsSolutions that address theBusiness Proprieties?

The above questions like above,have to be answered in theSystems Investigation Stage.


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Phase 1 : Systems Investigation

Feasibility Study:A feasibility study is a preliminary studywhere the information needs ofprospective users and the resourcerequirements, costs, benefits & feasibilityof a proposed project are determined.The goal of feasibility study is to evaluate alternativesystem solution and to propose the most feasible anddesirable business application for development.


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Systems Investigation

Organizational

Feasibility

Is it a good fit?

OperationalFeasibility

Will i t be accepted?

Economic

Feasibility

Can we afford it?

TechnicalFeasibility

Does the

capabil ity exist?


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Feasibility Study

Organizational Feasibility:-Q) How well a proposed Information

system fits the companys Sales,Marketing and Financial Plans?

Technical Feasibility:-Q) Whether we have technical resources

to build the new system?

Q) Whether we have to purchase newtechnology?


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Feasibility Study

Economic Feasibility:-Savings in Labour Costs?

Increased Sales Revenue?

Decreased Investment in Inventory?

Increased Profits?

Operational Feasibility:-

Acceptance by employees?Management Support?

Customer and supplier acceptance?


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Cost/ Benefit Analysis

Feasibility Studies typicallyinvolve Cost/ Benefit Analysis. If

costs and benefits can bequantified, they are called

tangible, if not they are calledas intangible.


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Cost/ BenefitAnalysis

Costs Benefits


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Cost/Benefit AnalysisCosts

Tangible Costs IntangibleCosts

Fixed

Costs

Recurring

Costs


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Benefits

Tangible

Benefits

Intangible

Benefits


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Tangible Benefits

Increase in Sales/ProfitsDecrease in Information

Processing costsDecrease in Operating Costs

Decrease in Required InvestmentsIncreased Operational Efficiency


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Intangible Benefits

Improved Decision MakingImproved abilities in analysis

Improved Customer serviceImproved Employee Morale

Improved Competitive PositionImproved Business Image


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Phase 2 : Systems Analysis

Systems Analysis is an indepth study of end userinformation needs, thatproduces functional

requirements that areused as the basis for thedesign of a newInformation system.

.

Systems

Requirements

Functional

Requirements

Technical

Requirements

i


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Systems Requirements

Stakeholders

User

Stakeholders

Client

Stakeholders

Technical

Stakeholders

U S k h ld


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User Stakeholders

User

Stakeholders

Business

OperationUsers

ManagementUsers

F tFi di


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Fact Finding

The objective of the analysis phase of

systems development is to understandthe business functions & develop thesystem requirements.

Q. What are the Business Processes and operations?

Q. How should the Business Processes be performed?

Q. What are the informationrequirements?

FactFindingTechniques


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Fact Finding Techniques

Fact

Finding

Techniques

QuestionnairesReview

DocumentsInterviewing

ObserveBusiness

Processes


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Questionnaires

Large number of audience.Discretion

Very good for Preliminary investigationTypes of Questions:-

Closed Ended QuestionsObjective Type Questions


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Review Documents

Good way to get a preliminaryunderstanding.

These documents serve as Visual aidsduring the interview itself.

It is better to have filled forms ratherthan blank forms.

Interview


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InterviewBefore

Objective

Correct Users

Project Team membersList of questions

During

Inform exact objectivesProbe for details

Look for exceptions

AfterReview Notes for accuracy

Transfer information into proper documents

Identify areas for further clarifications


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Observe Business Processes

There is no better way to learn howusers actually use a system and whatinformation they need than to observefirst hand work being done.

A Quick Walkthrough

Users nervous


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Systems Design

DataDesignData

Design

UserInterfaceDesign

UserInterfaceDesign

ProcessDesign

ProcessDesign

Screen, Form, Report

and Dialog Design

Data Element

Structure DesignProgram and

Procedure Design

Systems Design consists of design activities thatproduce systems specifications satisfying thefunctional requirements that were developed in the

systems analysis process


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User Interface Design

Key Guidelines:Aesthetics

Easy to NavigateSearchibility

End User development


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Data Design

Key Guidelines:Entities

AttributesRelationships

KeysReferential Integrity


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Process Design

Key Guidelines:Decision Structures

Choice of LoopsSubroutines

Call By Reference

Call By Value

Use of Global Variables


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Phase IV : ImplementingBusiness Systems

Systems Implementation stage involves hardwareand software acquisition, software development,testing of programs and procedures, development ofdocumentation and variety of conversion alternatives.

Implementation activities are required to transform anewly developed Information system into anoperational system for end users.

TheImplementationProcess


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The Implementation Process

ConversionConversionSystemDocumentation

SystemDocumentation

End UserTraining

End UserTraining

Developmentand

Modification

Developmentand

ModificationAcquisitionAcquisition

ImplementationActivities

ImplementationActivities

SystemTesting

SystemTesting

EvaluatingHardware software &services


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Evaluating Hardware, software & services

Suppliers place Bids and proposals

Minimum acceptable physical &performance characteristics areestablished

Requirements are finalised byfollowing documents:-

RFP

RFQ

Scoring System for evaluating

proposals.


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TestingSystem Testing may involve :-

Testing website performance

Testing & Debugging software

Testing should not only occur only during thesystems implementation stage, but

throughout systems development process.

Documentation


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Documentation

Internal

Documentation

External

Documentation


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Training

Its a vital implementation activityTraining must involve activities such asData Entry.

Training must also involve all aspects ofproper use of a new system.

IS personnel such as USER CONSULTANTmust be sure that end users are trained tooperate the new e business system, else

the implementation will fail.


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Conversion methods

The initial operation of a new businesssystem can be a difficult task. Ittypically involves conversion process

from the use of a present system to theoperation of a new or improvedapplication.

Conversion methods can soften theimpact of introducing new Information

Technologies into an organisation.

Installation Conversion Methods


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Installation Conversion Methods

Old SystemOld System New SystemNew System

Old SystemOld System

New SystemNew System

Old SystemOld System

Old SystemOld System New System

New System

Parallel

Pilot

Phased

Plunge

Conversionmethods


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Conversion methods

Parallel

Conversions can be done on a parallel, wherebyboth old and new systems are operating untilthe project development team & endusersagree for a complete switchover

PlungeInstallation is accomplished by a direct cutoveror plunge into the newly developed system.

Conversionmethods


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Conversion methods

Phased Basis

Conversions can be done in a phased basis,where only parts of a new application (fewdepartments, branch offices) at a time areconverted.

Pilot Conversion

Here one department serves as a Test Site. A

new system can be tried out at this site untildevelopers feel it can be implementedthroughout the organization.


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PHASE V : IS Maintenance

Systems Maintenanceis the monitoring,evaluating and modifying of operational businesssystems to make desirable or necessaryimprovements.

Maintenance is also necessary for other failures &problems that arise during the operation of asystems. End users and IS personnel then

perform a Trouble shooting function todetermine the causes of and solutions to suchproblems.


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IS Maintenance

Maintenance also includes makingmodifications to an established systemdue to changes in BusinessOrganizations or Business Environment.

EgEg : New Tax Legislation: New Tax Legislation

New eNew e business initiativesbusiness initiatives

TopicVII Information Systems Development

Documents

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