requirements engineering - requirements management
TRANSCRIPT
Requirements Engineering: Change Management &
Risk ManagementCECS 542
Dr.BirgitPenzenstadler1
Photocredit:PaulMorris,Unsplash
Recap<me!
• Qualityassurance– Whatarequalitydefects?– HowisQAdefined?– Whatisconstruc<veQA?– Whatisanaly<calQA?
Dr.BirgitPenzenstadler 2
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
Change&RiskManagement
Dr.BirgitPenzenstadler 4
Overview:Change&RiskManagement
• Recap:RequirementsManagement• ChangeManagement• RiskManagement
Dr.BirgitPenzenstadler 5
KRayker,stock.xchng
Recap:REintheprocess
Dr.BirgitPenzenstadler 6
Valida<onTraceabilityMatrix
Plan,decide,managerisks,managechanges
Risk&StatusReport
RequirementsEngineering
ProjectmanagementRequirementsManagement
RequirementsEngineering
AnalysisElicita<on
Documenta<on
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
Overview:Change&RiskManagement
• Recap:RequirementsManagement• ChangeManagement• RiskManagement
Dr.BirgitPenzenstadler 8
KRayker,stock.xchng
ChangeManagement–why?
Dr.BirgitPenzenstadler 9
KRayker,stock.xchng
Recap:A_ributesforrequirements• ID• Descrip<on• Owner• Stakeholder• Source• Ra<onale• State• AccceptanceCriterion• TimeConstraint• PriorityàMakesurealloftheseareupdatedinthechangeprocess
10
Managingrequirements
• Bigprojectsmayhavethousandsofrequirements• Formanagement,thestandardprocessis
1. Allaresubmi_edtoadatabase2. Andmanagedviatheira_ributes3. Fortherespec<vemilestone,requirementsare
decidedupon(„Freeze“/„Baseline“)4. Andohengatheredinadocumentforofficial
approvalà Aherthisofficialapproval,furtherchangeshavetoadheretoastandardizedchangeprocess
11
ChangeManagement–how?Foursteps• Systema<celicita<onofChangeRequests• Decisiononpriorityandcosts• Decisiononimplementa<on• Implementa<onofchangesImportantrelatedtasks:• Impactanalysis:Whatconsequencesdochangeshave?• Versionmanagement:Whichversionsofrequirementsexist?• Configura<onmanagement:Whichrequirementsformconsistent
baselines?• Defectmanagement:Howtodealwithdefectsandtheir
correc<on?
12
ChangeManagement–how?StatusofRequirement
Dr.BirgitPenzenstadler 13
KRayker,stock.xchng
Proposed
Assumption
Validated
Applied
Tested
Denied
ReleasedAccepted
Designed Implemented[Information System
Requirements]
[Other]
New Req
Overview:Change&RiskManagement
• Recap:RequirementsManagement• ChangeManagement• RiskManagement
Dr.BirgitPenzenstadler 14
KRayker,stock.xchng
RiskManagement
Dr.BirgitPenzenstadler 15
leadershipchamps.wordpress.com
Risksthatarerelatedtorequirementshavetobeiden<fied,assessedandanalyzed,sothatac<oncanbetakenearlyon.
RiskManagement
Dr.BirgitPenzenstadler 16www.pharmadirec<ons.com
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
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/
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/
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/
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/
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/
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/
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/
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/
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/
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/
RiskManagementTools
• SWOTanalysis(Strengths,weaknesses,opportuni<es,threats)
• Root-causeanalysis
Dr.BirgitPenzenstadler 28
SWOTanalysis
Dr.BirgitPenzenstadler 29CSULBspring2015
Root-causeanalysis
• (Strengths,weaknesses,opportuni<es,threats)
• Root-causeanalysis
Dr.BirgitPenzenstadler 30CSULBspring2015
Root-causeanalysis
• (Strengths,weaknesses,opportuni<es,threats)
• Root-causeanalysis
Dr.BirgitPenzenstadler 31
Root-causeanalysis
Dr.BirgitPenzenstadler 32CSULBspring2016
Root-causeanalysis
• (Strengths,weaknesses,opportuni<es,threats)
• Root-causeanalysis
Dr.BirgitPenzenstadler 33CSULBspring2015
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