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Requirements Engineering: Change Management & Risk Management CECS 542 Dr. Birgit Penzenstadler 1 Photo credit: Paul Morris, Unsplash

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Page 1: Requirements Engineering - Requirements management

Requirements Engineering: Change Management &

Risk ManagementCECS 542

Dr.BirgitPenzenstadler1

Photocredit:PaulMorris,Unsplash

Page 2: Requirements Engineering - Requirements management

Recap<me!

•  Qualityassurance– Whatarequalitydefects?– HowisQAdefined?– Whatisconstruc<veQA?– Whatisanaly<calQA?

Dr.BirgitPenzenstadler 2

Page 3: Requirements Engineering - Requirements management

Connec<ontoReqMngmt

Dr.BirgitPenzenstadler 3

QAbecauseresultsofREareneededfor

Life cycle of a requirement

3

Context Layer

System Layer

Requirements Layer

Stakeholder Model Objectives & Goals

Constraints & Rules

!

!

!

!

!

Data Model

EA

A AE

System Vision

Functional Hierarchy

Architecture Overview

System

Function ModelFun 1

Fun 2

Component Model

C C

Data Model

EA

A AE

Behaviour Model

Business Case

Deployment Requirements

System Constraints

Domain Model

Service ModelUsage Model

Quality Requirements

Risk List

Project Scope

Process Requirements

Glossary

Glossary

Glossary

Design

Implementa<on

Test(Integra<ontest,systemtest,acceptancetest)

Userdocumenta<on

Projectorganiza<onandmanagement

Configura<onmanagement

Page 4: Requirements Engineering - Requirements management

Change&RiskManagement

Dr.BirgitPenzenstadler 4

Page 5: Requirements Engineering - Requirements management

Overview:Change&RiskManagement

•  Recap:RequirementsManagement•  ChangeManagement•  RiskManagement

Dr.BirgitPenzenstadler 5

KRayker,stock.xchng

Page 6: Requirements Engineering - Requirements management

Recap:REintheprocess

Dr.BirgitPenzenstadler 6

Valida<onTraceabilityMatrix

Plan,decide,managerisks,managechanges

Risk&StatusReport

RequirementsEngineering

ProjectmanagementRequirementsManagement

RequirementsEngineering

AnalysisElicita<on

Documenta<on

Page 7: Requirements Engineering - Requirements management

RequirementsManagement:Tasks

7

•  Ra<onaleManagementandTraceability–  Ra<onaleforrequirements–  Rela<onbetweencontentitems

•  Managementoftherequirements–  Structuring,documenta<onandarchiving–  A_ribu<on

•  Interdependencywithothermanagementtasks–  Valida<onandVerifica<on–  ChangemanagementandImpactAnalysis–  Versionmanagement–  Configura<onmanagement–  Claimmanagement–  SupportfordistributedRE–  ToolsupportforRM

Page 8: Requirements Engineering - Requirements management

Overview:Change&RiskManagement

•  Recap:RequirementsManagement•  ChangeManagement•  RiskManagement

Dr.BirgitPenzenstadler 8

KRayker,stock.xchng

Page 9: Requirements Engineering - Requirements management

ChangeManagement–why?

Dr.BirgitPenzenstadler 9

KRayker,stock.xchng

Page 10: Requirements Engineering - Requirements management

Recap:A_ributesforrequirements•  ID•  Descrip<on•  Owner•  Stakeholder•  Source•  Ra<onale•  State•  AccceptanceCriterion•  TimeConstraint•  PriorityàMakesurealloftheseareupdatedinthechangeprocess

10

Page 11: Requirements Engineering - Requirements management

Managingrequirements

•  Bigprojectsmayhavethousandsofrequirements•  Formanagement,thestandardprocessis

1.  Allaresubmi_edtoadatabase2.  Andmanagedviatheira_ributes3.  Fortherespec<vemilestone,requirementsare

decidedupon(„Freeze“/„Baseline“)4.  Andohengatheredinadocumentforofficial

approvalà Aherthisofficialapproval,furtherchangeshavetoadheretoastandardizedchangeprocess

11

Page 12: Requirements Engineering - Requirements management

ChangeManagement–how?Foursteps•  Systema<celicita<onofChangeRequests•  Decisiononpriorityandcosts•  Decisiononimplementa<on•  Implementa<onofchangesImportantrelatedtasks:•  Impactanalysis:Whatconsequencesdochangeshave?•  Versionmanagement:Whichversionsofrequirementsexist?•  Configura<onmanagement:Whichrequirementsformconsistent

baselines?•  Defectmanagement:Howtodealwithdefectsandtheir

correc<on?

12

Page 13: Requirements Engineering - Requirements management

ChangeManagement–how?StatusofRequirement

Dr.BirgitPenzenstadler 13

KRayker,stock.xchng

Proposed

Assumption

Validated

Applied

Tested

Denied

ReleasedAccepted

Designed Implemented[Information System

Requirements]

[Other]

New Req

Page 14: Requirements Engineering - Requirements management

Overview:Change&RiskManagement

•  Recap:RequirementsManagement•  ChangeManagement•  RiskManagement

Dr.BirgitPenzenstadler 14

KRayker,stock.xchng

Page 15: Requirements Engineering - Requirements management

RiskManagement

Dr.BirgitPenzenstadler 15

leadershipchamps.wordpress.com

Risksthatarerelatedtorequirementshavetobeiden<fied,assessedandanalyzed,sothatac<oncanbetakenearlyon.

Page 16: Requirements Engineering - Requirements management

RiskManagement

Dr.BirgitPenzenstadler 16www.pharmadirec<ons.com

Page 17: Requirements Engineering - Requirements management

Exercise:Avoiddisasters

1. Whatistheprobleminthefollowingsitua9ons?

2. Howcouldithavebeenavoided?(in3,5,and7)

Dr.BirgitPenzenstadler 17

Context Layer

System Layer

Requirements Layer

Stakeholder Model Objectives & Goals

Constraints & Rules

!

!

!

!

!

Data Model

EA

A AE

System Vision

Functional Hierarchy

Architecture Overview

System

Function ModelFun 1

Fun 2

Component Model

C C

Data Model

EA

A AE

Behaviour Model

Business Case

Deployment Requirements

System Constraints

Domain Model

Service ModelUsage Model

Quality Requirements

Risk List

Project Scope

Process Requirements

Glossary

Glossary

Glossary

Page 18: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

1.FaultySovietearlywarningsystemnearlycausesWWIII(1983)Thethreatofcomputerspurposefullystar<ngWorldWarIIIiss<llthestuffofsciencefic<on,butaccidentalsohwareglitcheshavebroughtusworryinglycloseinthepast.Althoughtherearenumerousallegedeventsofthisilk,thesecrecyaroundmilitarysystemsmakesithardtosorttheurbanmythsfromtherealincidents.However,oneexamplethatiswellrecordedhappenedbackin1983,andwasthedirectresultofasohwarebugintheSovietearlywarningsystem.TheRussians'systemtoldthemthattheUShadlaunchedfiveballis<cmissiles.However,thedutyofficerforthesystem,oneLtColStanislavPetrov,claimshehada"...funnyfeelinginmygut",andreasonediftheUSwasreallya_ackingtheywouldlaunchmorethanfivemissiles.Thetriggerforthenearapocalyp<cdisasterwastracedtoafaultinsohwarethatwassupposedtofilteroutfalsemissiledetec<onscausedbysatellitespickingupsunlightreflec<onsoffcloud-tops.

Dr.BirgitPenzenstadler 18h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 19: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

2.TheAT&Tnetworkcollapse(1990)In1990,75millionphonecallsacrosstheUSwentunansweredaherasingleswitchatoneofAT&T's114switchingcentressufferedaminormechanicalproblem,whichshutdownthecentre.Whenthecentrecamebackupsoonaherwards,itsentamessagetoothercentres,whichinturncausedthemtotripandshutdownandreset.Theculpritturnedouttobeanerrorinasinglelineofcode—nothackers,assomeclaimedatthe<me—thathadbeenaddedduringahighlycomplexsohwareupgrade.AmericanAirlinesalonees<matedthissmallerrorcostit200,000reserva<ons.

Dr.BirgitPenzenstadler 19h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 20: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

3.TheexplosionoftheAriane5(1996)In1996,Europe'snewestandunmannedsatellite-launchingrocket,theAriane5,wasinten<onallyblownupjustsecondsahertakingoffonitsmaidenflightfromKourou,FrenchGuiana.TheEuropeanSpaceAgencyes<matedthattotaldevelopmentofAriane5costmorethan$8bn(£4bn).OnboardAriane5wasa$500m(£240m)setoffourscien<ficsatellitescreatedtostudyhowtheEarth'smagne<cfieldinteractswithSolarWinds.AccordingtoapieceintheNewYorkTimesMagazine,theself-destruc<onwastriggeredbysohwaretryingtostuff"a64-bitnumberintoa16-bitspace"."Thisshutdownoccurred36.7secondsaherlaunch,whentheguidancesystem'sowncomputertriedtoconvertonepieceofdata—thesidewaysvelocityoftherocket—froma64-bitformattoa16-bitformat.Thenumberwastoobig,andanoverflowerrorresulted.Whentheguidancesystemshutdown,itpassedcontroltoaniden<cal,redundantunit,whichwastheretoprovidebackupincaseofjustsuchafailure.Butthesecondunithadfailedintheiden<calmannerafewmillisecondsbefore.Andwhynot?Itwasrunningthesamesohware,"thear<clestated.

Dr.BirgitPenzenstadler 20h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 21: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

4.AirbusA380suffersfromincompaQblesoRwareissues(2006)TheAirbusissueof2006highlightedaproblemmanycompaniescanhavewithsohware:whathappenswhenoneprogramdoesn'ttalktotheanother.Inthiscase,theproblemwascausedbytwohalvesofthesameprogram,theCATIAsohwarethatisusedtodesignandassembleoneoftheworld'slargestaircrah,theAirbusA380.ThiswasamajorEuropeanundertakingand,accordingtoBusinessWeek,theproblemarosewithcommunica<onsbetweentwoorganisa<onsinthegroup:theFrenchDassaultAvia<onandaHamburgfactory.Putsimply,theGermansystemusedanout-of-dateversionofCATIAandtheFrenchsystemusedthelatestversion.SowhenAirbuswasbringingtogethertwohalvesoftheaircrah,thedifferentsohwaremeantthatthewiringononedidnotmatchthewiringintheother.Thecablescouldnotmeetupwithoutbeingchanged.Theproblemwaseventuallyfixed,butonlyatacostthatnobodyseemstowanttoputanabsolutefigureon.Butallagreeditcostalot,andputtheprojectbackayearormore.

Dr.BirgitPenzenstadler 21h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 22: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

5.MarsClimateObservermetricproblem(1998)Twospacecrah,theMarsClimateOrbiterandtheMarsPolarLander,werepartofaspaceprogrammethat,in1998,wassupposedtostudytheMar<anweather,climate,andwaterandcarbondioxidecontentoftheatmosphere.Butaproblemoccurredwhenanaviga<onerrorcausedthelandertoflytoolowintheatmosphereanditwasdestroyed.Whatcausedtheerror?Asub-contractorontheNasaprogrammehadusedimperialunits(asusedintheUS),ratherthantheNasa-specifiedmetricunits(asusedinEurope).

Dr.BirgitPenzenstadler 22h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 23: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

6.EDSandtheChildSupportAgency(2004)BusinessservicesgiantEDSwadedinwiththisspectaculardisaster,whichassistedinthedestruc<onoftheChildSupportAgency(CSA)andcostthetaxpayeroverabillionpounds.EDS'sCS2computersystemsomehowmanagedtooverpay1.9millionpeopleandunderpayaround700,000,partlybecausetheDepartmentforWorkandPensions(DWP)decidedtoreformtheCSAatthesame<measbringinginCS2.EdwardLeigh,chairmanofthePublicAccountsCommi_ee,wasoutragedwhentheNa<onalAuditOfficesubsequentlypickedthroughthewreckage:"Ignoringamplewarnings,theDWP,theCSAandITcontractorEDSintroducedalarge,complexITsystematthesame<measrestructuringtheagency.Thenewsystemwasbroughtinand,asnightfollowsday,stumbledandnowhasenormousopera<onaldifficul<es."

Dr.BirgitPenzenstadler 23h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 24: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

7.Thetwo-digityear-2000problem(1999/2000)AlotofITvendorsandcontractorsdidverywelloutofthebillionsspenttoavoidwhatmanyfearedwouldbethedisasterrelatedtotheMillenniumBug.Rumoursofastronomicalcontractratesandretainersabounded.Andthesoundofclocksstrikingmidnightin<mezonesaroundtheworldwasfollowedby...notpanic,notcrashingcomputersystems,infactnothingmorethannewyearcelebra<ons.Sowhyincludeithere?Thatthepredic<onsofdoomcametonaughtisirrelevant,aswe'renottalkingaboutthedisasterthatwasaverted,buttheoriginaldisastrousdecisiontouseandkeepusingforlongerthanwaseithernecessaryorprudentdoubledigitsforthedatefieldincomputerprograms.AreportbytheHouseofCommonsLibrarypeggedthecostoffixingthebugat£400bn.AndthatiswhytheMillenniumBugdeservesaplaceinthetop10.

Dr.BirgitPenzenstadler 24h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 25: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

8.Whenthelaptopsexploded(2006)Itallbegansimply,butcertainlynotquietly,whenalaptopmanufacturedbyDellburstintoflamesatatradeshowinJapan.Therehadbeenrumoursoflaptopscatchingfire,butthedifferenceherewasthattheDelllaptopmanagedtodoitinthefullglareofpublicityandvideocaptureditinfullcolour.(Unfortunately,thevideocapturingtheincidentappearstohavevanishedfromtheweb.Ifyouhappentoownacopy,pleasesendittousasitshouldmakeinteres<ngviewingagain.)"Wehavecapturedthenotebookandhavebeguninves<ga<ngtheevent,"DellspokeswomanAnneCamdenreportedatthe<me,andinves<gateDelldid.Attheendoftheseinves<ga<onstheproblemwastracedtoanissuewiththeba_ery/powersupplyontheindividuallaptopthathadoverheatedandcaughtfire.ItwasanexpensiveissueforDelltosortout.Asaresultofitsinves<ga<onDelldecidedthatitwouldbeprudenttorecallandreplace4.1mlaptopba_eries.Companychiefexecu<veMichaelDelleventuallylaidtheblametheforthefaultyba_erieswiththemanufactureroftheba_erycells—Sony.Butthatwasn’ttheendofit.ApplereportedissuesforiPodsandMacbooksandmanyPCsuppliersreportedthesame.Matsushitaalonehashadtorecallaround54milliondevices.Sonyes<matedatthe<methattheoverallcostofsuppor<ngtherecallprogrammesofAppleandDellwouldamounttobetween¥20bn(£90m)and¥30bn.

Dr.BirgitPenzenstadler 25h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 26: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

9.Siemensandthepassportsystem(1999)Itwasthesummerof1999,andhalfamillionBri<shci<zenswerelessthanhappytodiscoverthattheirnewpassportscouldn'tbeissuedon<mebecausethePassportAgencyhadbroughtinanewSiemenscomputersystemwithoutsufficientlytes<ngitandtrainingstafffirst.HundredsofpeoplemissedtheirholidaysandtheHomeOfficehadtopaymillionsincompensa<on,staffover<meandumbrellasforthepoorpeoplequeuingintherainforpassports.Butwhysuchanunexpectedlyhugedemandforpassports?Thelawhadrecentlychangedtodemand,forthefirst<me,thatallchildrenunder16hadtogetoneiftheyweretravellingabroad.ToryMPAnneWiddecombesummeditupwellwhilebera<ngthethenhomesecretary,JackStraw,overthefiasco:"Commonsenseshouldhavetoldhimthattochangethelawonchildpassportsatthesame<measintroducinganewcomputersystemintotheagencywasstoringuptroubleforthefuture."

Dr.BirgitPenzenstadler 26h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 27: Requirements Engineering - Requirements management

Thetop10ITdisastersofall<me

10.LAAirportflightsgrounded(2007)Some17,000planesweregroundedatLosAngelesInterna<onalAirportearlierthisyearbecauseofasohwareproblem.TheproblemthathitsystemsatUnitedStatesCustomsandBorderProtec<on(USCBP)agencywasasimpleonecausedinapieceoflowly,inexpensiveequipment.Thedeviceinques<onwasanetworkcardthat,insteadofshuxngdownasperhapsitshouldhavedone,persistedinsendingtheincorrectdataoutacrossthenetwork.Thedatathencascadedoutun<lithittheen<renetworkattheUSCBPandbroughtittoastands<ll.NobodycouldbeauthorisedtoleaveorentertheUSthroughtheairportforeighthours.Passengerswerenotimpressed.

Dr.BirgitPenzenstadler 27h_p://www.zdnet.com/the-top-10-it-disasters-of-all-<me-3039290976/

Page 28: Requirements Engineering - Requirements management

RiskManagementTools

•  SWOTanalysis(Strengths,weaknesses,opportuni<es,threats)

•  Root-causeanalysis

Dr.BirgitPenzenstadler 28

Page 29: Requirements Engineering - Requirements management

SWOTanalysis

Dr.BirgitPenzenstadler 29CSULBspring2015

Page 30: Requirements Engineering - Requirements management

Root-causeanalysis

•  (Strengths,weaknesses,opportuni<es,threats)

•  Root-causeanalysis

Dr.BirgitPenzenstadler 30CSULBspring2015

Page 31: Requirements Engineering - Requirements management

Root-causeanalysis

•  (Strengths,weaknesses,opportuni<es,threats)

•  Root-causeanalysis

Dr.BirgitPenzenstadler 31

Page 32: Requirements Engineering - Requirements management

Root-causeanalysis

Dr.BirgitPenzenstadler 32CSULBspring2016

Page 33: Requirements Engineering - Requirements management

Root-causeanalysis

•  (Strengths,weaknesses,opportuni<es,threats)

•  Root-causeanalysis

Dr.BirgitPenzenstadler 33CSULBspring2015

Page 34: Requirements Engineering - Requirements management

Take-away:

•  RequirementsManagement– Majortasks– ChangeManagement– RiskManagement

Dr.BirgitPenzenstadler 34

Context Layer

System Layer

Requirements Layer

Stakeholder Model Objectives & Goals

Constraints & Rules

!

!

!

!

!

Data Model

EA

A AE

System Vision

Functional Hierarchy

Architecture Overview

System

Function ModelFun 1

Fun 2

Component Model

C C

Data Model

EA

A AE

Behaviour Model

Business Case

Deployment Requirements

System Constraints

Domain Model

Service ModelUsage Model

Quality Requirements

Risk List

Project Scope

Process Requirements

Glossary

Glossary

Glossary