Quality Mgmt in S/W ? ByQuality Mgmt in S/W ? By

Dr.S.Sridhar, Ph.D.(JNUD),Dr.S.Sridhar, Ph.D.(JNUD),RACI(Paris, NICE), RMR(USA), RZFM(Germany)RACI(Paris, NICE), RMR(USA), RZFM(Germany)

DIRECTOR-TechnicalDIRECTOR-TechnicalEinstein College of EngineeringEinstein College of Engineering

Quality Check in • programs • documents • data ...

Software Software Applications Applications

which need Quality which need Quality system softwaresystem software real-time softwarereal-time software business softwarebusiness software engineering/scientific engineering/scientific

softwaresoftware embedded softwareembedded software PC softwarePC software AI softwareAI software WebApps (Web applications)WebApps (Web applications)

Software Engineering

Quality on Layered Quality on Layered TechnologyTechnology

Software Engineering

a “quality” focusa “quality” focus

process modelprocess model

methodsmethods

toolstools

Quality in Process as Problem Quality in Process as Problem SolvingSolving

statusquo

problemdefinition

technicaldevelopment

solutionintegration

The Primary The Primary Goal:Goal:

High QualityHigh QualityRemember:Remember:

High quality = project timelinessHigh quality = project timeliness

Why?Why?

Less rework!Less rework!

Quality from Analysis to Quality from Analysis to DesignDesign

Entity-Relationship

Diagram

Data FlowDiagram

State-TransitionDiagram

Data Dictionary

Process Specification (PSPEC)

Control Specification (CSPEC)

Data Object Description

THE ANALYSIS MODEL

proceduraldesign

interfacedesign

architecturaldesign

datadesign

THE DESIGN MODEL

Where Do We Where Do We Begin?Begin?

Spec

PrototypePrototype

DesignDesign

modeling

Quality Quality thinking !thinking !

MODULE

What's inside??

How big is it??

Quality on Interface Quality on Interface DesignDesign

Easy to use?Easy to use?

Easy to understand?Easy to understand?

Easy to learn?Easy to learn?

Golden Rules for Golden Rules for qualityquality

Place the user in controlPlace the user in control Reduce the user’s memory Reduce the user’s memory

loadload Make the interface consistentMake the interface consistent

Quality on Design Evaluation Quality on Design Evaluation CycleCyclepreliminary

design

buildprototype #1

interface

evaluationis studied by

designer

designmodifications

are made

buildprototype # n

interface

userevaluate'sinterface

Interface designis complete

Quality Software Quality Software TestingTesting

Testing is the process of exercising aTesting is the process of exercising aprogram with the specific intent of findingprogram with the specific intent of findingerrors prior to delivery to the end user.errors prior to delivery to the end user.

What Testing ShowsWhat Testing Shows

errorserrors

requirements conformancerequirements conformance

performanceperformance

an indicationan indicationof qualityof quality

Who Tests the Who Tests the Software?Software?

developerdeveloper independent testerindependent tester

Understands the system Understands the system

Black-Box Testing Black-Box Testing qualityquality

requirementsrequirements

eventseventsinputinput

outputoutput

Quality Testing StrategyQuality Testing Strategyunit testunit test integrationintegration

testtest

validationvalidationtesttest

systemsystemtesttest

The Debugging The Debugging ProcessProcess

test casestest cases

resultsresults

DebuggingDebugging

suspectedsuspectedcausescauses

identifiedidentifiedcausescauses

correctionscorrections

regressionregressionteststests

new testnew testcasescases

Consequences of BugsConsequences of Bugs

damagedamage

mildmild annoyingannoying

disturbingdisturbingseriousserious

extremeextremecatastrophiccatastrophic

infectiousinfectious

Bug TypeBug Type

Bug Categories:Bug Categories: function-related bugs, function-related bugs, system-related bugs, data bugs, coding bugs, system-related bugs, data bugs, coding bugs, design bugs, documentation bugs, standards design bugs, documentation bugs, standards violations, etc.violations, etc.

WebApp Quality WebApp Quality FactorsFactors

Good luck and best wishesGood luck and best wishes from Dr.S.Sridhar from Dr.S.Sridhar

For any further help, please get in touch with For any further help, please get in touch with me over drssridhar@yahoo.comme over drssridhar@yahoo.com