COSOSIMO Parameter Definitions.docx

COSOSIMO Parameter Definitions.docx

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COSOSIMOParameterDefinitions

COSOSIMOParameterDefinitions

JoAnnLane

UniversityofSouthernCalifornia

CenterforSystemsandSoftwareEngineering

jolane@usc.edu

Introduction

TheConstructiveSystem-of-Systems（SoS）IntegrationCostModel（COSOSIMO）isdesignedtoestimatetheeffortassociatedwiththeLeadSystemIntegrator（LSI）activitiestodefinetheSoSarchitecture,identifysourcestoeithersupplyordeveloptherequiredSoScomponentsystems,andeventuallyintegrateandtestthesehighlevelcomponentsystems.Forthepurposesofthiscostmodel,anSoSisdefinedasanevolutionarynet-centricarchitecturethatallowsgeographicallydistributedcomponentsystemstoexchangeinformationandperformtaskswithintheframeworkthattheyarenotcapableofperformingontheirownoutsideoftheframework.ThecomponentsystemsmayoperatewithintheSoSframeworkaswellasoutsideoftheframework,andmaydynamicallycomeandgoasneededoravailable.Inaddition,thecomponentsystemsaretypicallyindependentlydevelopedandmanagedbyorganizations/vendorsotherthantheSoSsponsorsortheLSI.

ResultsofrecentCOSOSIMOworkshopshaveresultedinthedefinitionofthreeCOSOSIMOsub-models:

aplanning/requirementsmanagement/architecture（PRA）sub-model,asourceselectionandsupplieroversight（SS）sub-model,andanSoSintegrationandtesting（I&T）sub-model.Theconceptualeffortprofilesforeachsub-modelareshowninFigure1.

Figure1.ConceptualOverviewofCOSOSIMOSub-Models.

ThistechnicalreportisanupdatetotheCOSOSIMOparameterdefinitionsdatedMarch2006anddescribestheparametersforeachoftheCOSOSIMOsub-models.Theparametersincludeasetofsizedriversthatareusedtocalculateanominaleffortforthesetsofactivitiesassociatedwiththesub-modelandasetofcostdriversthatareusedtoadjustthenominaleffortbasedonrelatedSoSarchitecture,process,andpersonnelcharacteristics.Eachsizedriverdescriptionincludesadefinitionoftheparameteraswellasassociatedcountingrulesandguidanceforassigningcomplexityratings.Eachcostdriverdescriptionincludesadefinitionoftheparameteraswellasguidanceforassigningtheappropriateratingfactor.

Finally,COSOSIMOworkshopfindingsindicatethatsomeoftheSoSLSIactivitiesaresimilartosystemsengineeringactivitiesaddressedbytheConstructiveSystemsEngineeringCostModel（COSYSMO）andhavesimilarsizeandcostdrivers.Therefore,someoftheCOSOSIMOparameterdefinitionsareadaptedfromtheCOSYSMOdefinitionsin[Valerdi2005]andareindicatedbyafootnote.

COSOSIMOPRAParameters

TheLSIPRAactivitiesarethoseassociatedwithSoSconceptdevelopment;requirementsidentification,analysis,andevolution;SoSarchitecturedevelopmentandevolution,aswellasthelongtermplanningforprovidingincrementalSoScapabilitiesinaccordancewiththeSoSsponsor’scostandscheduletargets.

PRASizeDrivers

NumberofSoS-RelatedRequirements:

ThisdriverrepresentsthenumberofrequirementsfortheSoSofinterestattheSoSlevel.Requirementsmaybefunctional,performance,feature,orservice-orientedinnaturedependingonthemethodologyusedforspecification.Theymayalsobedefinedbythecustomerorcontractor.SoSrequirementscantypicallybequantifiedbycountingthenumberofapplicableshalls,wills,shoulds,andmaysintheSoSormarketingspecification.Note:

someworkmayberequiredtodecomposerequirementstoaconsistentlevelsothattheymaybecountedaccuratelyfortheappropriateSoS-of-interest.Table1containsthecomplexitydefinitionsfortheSoS-relatedrequirements.

SoS相关需求数：

这个因子表现了在该SoS层级上的相关SoS需求的数量。

需求可以是面向功能、性能、特性或服务，实际取决于系统规格的具体说明方式。

SoS需求一般可通过计算出SoS规格或营销规范说明书中类似于“应（达到）”或“要（达到）”的词句数量来确定。

注意：

有时候可能需要把需求分解成相同层级的多个小需求，以便更加精确的统计其数量。

Table1.SoS-RelatedRequirementsComplexityRatings.

Easy

Nominal

Difficult

Simpletoimplement

Familiar

Complextoimplementorengineer

Traceabletosource

Canbetracedtosourcewithsomeeffort

Hardtotracetosource

Littlerequirementsoverlap

Someoverlap

Highdegreeofrequirementsoverlap

NumberofSoSInterfaceProtocols:

Thenumberofdistinctnet-centricinterfaceprotocolstobeprovided/supportedbytheSoSframework.Note:

ThisdoesNOTincludeinterfacesinternaltotheSoScomponentsystems,butitdoesincludeinterfacesexternaltotheSoSandbetweentheSoScomponentsystems.Alsonotethatthisisnotacountoftotalinterfaces（inmanySoSs,thetotalnumberofinterfacesmaybeverydynamicascomponentsystemscomeandgointheSoSenvironment—inaddition,theremaybemultipleinstancesofagiventypeofcomponentsystem）,butratheracountofdistinctprotocolsattheSoSlevel.Table2containsthecomplexitydefinitionsfortheSoSinterfaceprotocols.

SoS接口协议数：

在SoS框架中需要分别提供或给予支持的网络中心接口协议的数量。

注意：

它并不包括SoS组件系统内部的接口，但它包括了由外部提供给SoS的接口，以及SoS成员系统之间的接口。

还需注意的是，它并不是对所有接口总数的计算（在很多SoS中，其接口的总数可能是不断变化的，这是由于在SoS运行环境中，组件系统可能会有所增减——另外，一个特定类型的组件系统也可能会出现多个实例），而是在SoS层级上对独立接口数量的统计。

Table2.InterfaceProtocolComplexityRatings.

Easy

Nominal

Difficult

Simpleprotocol

Moderatelycomplexprotocol

Highlycomplexornewprotocol（s）

MayalreadybesupportedbyseveralSoScomponentsystems

MayalreadybesupportedbysomeSoScomponentsystems

CurrentlysupportedbyfewifanySoScomponentsystems

Uncoupled

Looselycoupled

Highlycoupled

Wellunderstood

Predictablebehavior

Noteasilypredicable

PRACostDrivers

RequirementsUnderstanding1:

ThiscostdriverratesthelevelofunderstandingoftheSoSrequirementsbyalloftheSoSstakeholdersincludingtheSoScustomersandsponsors,SoSPRAteammembers,componentsystemowners,users,etc.Primarysourcesofaddedsystemsengineeringeffortareunprecedentedcapabilities,unfamiliardomains,orcapabilitieswhoserequirementsareemergentwithuse.Table3definesthevariousratingvaluesfortherequirementsunderstandingcostdriver.（Note:

TheseratingdefinitionsarethesameastheonesfortheSSandI&Trequirementsunderstandingcostdrivers,butshouldbeevaluatedintermsofthelevelofunderstandingbetweenthealloftheSoSstakeholderswithemphasisontheSoSPRAteammembers.）

需求理解度：

这个因子统计出了所有SoS利益相关者们（包括SoS客户与赞助者、SoSPRA团队成员、各组件系统的所有者、用户等等）对SoS需求的理解程度。

导致额外的系统工程工作的首要因素是前所未有的新技能、不熟悉的领域，以及需要紧急投入应用的技能。

Table3.PRARequirementsUnderstandingRatings.

Verylow

Low

Nominal

High

VeryHigh

Poor:

emergentrequirementsorunprecedentedcapabilities

Minimal:

manyundefinedareas

Reasonable:

someundefinedareas

Strong:

fewundefinedareas

Fullunderstandingofrequirements,familiarcapabilities

LevelofServiceRequirements1:

ThiscostdriverratesthedifficultyandcriticalityofsatisfyingtheensembleoflevelofservicerequirementsorKeyPerformanceParameters（KPPs）,suchassecurity,safety,transactionspeed,communicationlatency,interoperability,flexibility/adaptability,andreliability.Table4definesthevariousratingvaluesforthelevelofservicerequirementscostdriver.（Note:

TheseratingdefinitionsarethesameastheonesfortheSSandI&Tlevelofservicerequirementscostdrivers,butshouldbeevaluatedintermsoftheirimpactstothePRAactivities.）

服务需求水平：

这个因子统计出了满足全层级服务需求或者关键性能参数（KPP）的困难与临界点。

例如：

保密性、安全性、业务速度、交流速度、协同性、灵活性/适应性以及可靠性。

Table4.PRALevelofServiceRequirementsRatings.

Aspect

Verylow

Low

Nominal

High

VeryHigh

Difficulty

Simple;singledominantKPP

Low,somecouplingamongKPPs

Moderatelycomplex,coupledKPPs

Difficult,coupledKPPsorsomeconflictsbetweenKPPsmayberequiringtradeoffs

Verycomplex,tightlycoupledKPPsorsignificantconflictsbetweenKPPsrequiringtradeoffs

Criticality

Slightinconvenience

Easilyrecoverablelosses

Someloss

Highfinancialloss

Risktohumanlife

SoSStakeholderTeamCohesion1:

Representsamulti-attributeparameterwhichincludesleadership,sharedvision,diversityofstakeholders,approvalcycles,groupdynamics,IntegratedProductTeam（IPT）framework,teamdynamics,trust,andamountofchangeinresponsibilities.Itfurtherrepresentstheheterogeneityinstakeholdercommunityoftheendusers,customers,implementers,anddevelopmentteam.Table5definesthevariousratingvaluesfortheSoSstakeholderteamcohesioncostdriver.（Note:

TheseratingdefinitionsarethesameastheonesfortheSSandI&Tteamcohesioncostdrivers,butshouldbeevaluatedintermsofpotentialimpactstothePRAactivities.）

SoS利益相关者的团队凝聚力：

表现为一个多重属性的参数，包括领导能力、共同愿景、利益相关者的差异性、审批周期、群体动力、集成产品开发团队（IPT）的构架、团队动力、信赖度和岗位职责的变动量。

它进一步体现了利益相关者们比如终端用户、客户、实施者和开发团队之间的异质性。

Table5.SoSStakeholderTeamCohesionRatings.

Aspect

VeryLow

Low

Nominal

High

VeryHigh

Culture

Stakeholderswithdiverseexpertise,tasknature,language,culture,infrastructure

Highlyheterogeneousstakeholdercommunities

Heterogeneousstakeholdercommunity

Somesimilaritiesinlanguageandculture

Sharedprojectculture

Strongteamcohesionandprojectculture

Multiplesimilaritiesinlanguageandexpertise

Virtuallyhomogeneousstakeholdercommunities

Institutionalizedprojectculture

Compatibility

Highlyconflictingorganizationalobjectives

Convergingorganizationalobjectives

Compatibleorganizationalobjectives

Clearrolesandresponsibilities

Strongmutualadvantagetocollaboration

Familiarityandtrust

Lackoftrust

Willingtocollaborate,littleexperience

Somefamiliarityandtrust

Extensivesuccessfulcollaboration

Veryhighleveloffamiliarityandtrust

LSIPRATeamCapability:

RepresentstheanticipatedlevelofPRAteamcooperationandcohesion,personnelcapabilityandcontinuity,aswellasPRApersonnelexperiencewiththerelevantdomains,applications,language,andtoolsforSoSLSIpersonnelworkingonth