} Make reqs elicit at ion t raceable - How Crit ical det ails t o - - PDF document

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RESS ‘94

Making Requirement s Elicit at ion Traceable

Orlena Got el & Ant hony Finkelst ein

RSRS v7 v8 RS v6

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An Overview...

Meet ing cust omer needs:

• Problems & progress
• I mport ance of RT

RT t ypes & t heir pot ent ial:

• Why
• How

Crit ical det ails t o obt ain & render t raceable:

• Cont ribut ion st ruct ures
• Proposed approach

Quest ions f or workshop Make reqs elicit at ion t raceable

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RESS ‘94

Why Needs Are Not Met ...

Obt ain Specif y Use I dent if icat ion & involvement Techniques & pract ice Transcript ion Viewpoint s Emergence & change

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Progress I n Meet ing Needs...

Reqs elicit at ion:

• Obt ain needs

Reqs descript ion:

• Record needs

Development met hods:

• Use needs

Assurances? Connect ion bet ween elicit ed inf o, derived reqs & subsequent art if act s Reqs t raceabilit y:

• Augment needs
• Meet needs
• Change needs

Guarant ees?

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RESS ‘94

Some Terminology...

“ Requirement s Traceabilit y (RT) ref ers t o t he abilit y t o describe & f ollow t he lif e of a requirement in bot h a f orwards & backwards direct ion” (i.e., From it s origins, t hrough it s development & specif icat ion, t o it s subsequent deployment & use, & t hrough all periods of on-going ref inement & it erat ion in any of t hese phases)

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Some More Terminology...

“Post -RS Traceabilit y is concerned wit h t hose aspect s of a requirement ’s lif e t hat result f rom it s inclusion in t he RS” “Pre-RS Traceabilit y is concerned wit h t hose aspect s of a requirement ’s lif e prior t o it s inclusion in t he RS” (i.e., Requirement deployment ) (i.e., Requirement product ion)

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RESS ‘94

Pre-RS & Post -RS Traceabilit y...

Reqs art if act s produced (relat ed t o product ion) Reqs art if act s produced (relat ed t o deployment ) RS

s0 s1 sn

Pre Post

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Persist ent RT Problems...

Traceabilit y Of what (inf ormat ional requirement s) I n what way (access & present at ional requirement s)

&

Depends on Who want s it (user charact erist ics) Why t hey want it (t ask charact erist ics) When t hey want it (proj ect & cont ext ual charact erist ics)

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RESS ‘94

Crux Of RT Problems...

....mmm.... No Can Do Can you help me locat e & access personnel? I t is a f undament al working pract ice... I need t o back up & augment inf o!

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Traceabilit y Of Requirement s Cont ribut ors & Cont ribut ions...

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Model cont ribut ion st ruct ure underlying reqs:

I can t race personnel I can ident if y sources of reqs-relat ed work We can ident if y sources

• f reqs

We can locat e personnel I can ident if y sources of reqs-relat ed inf o

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RESS ‘94

Our Approach (1)...

11 Document or Principal Aut hor Art if act Cont ribut ed_t o Cont ribut ed_by

Def ine cont ribut ion f ormat of art if act : P: agent whose posit ion or belief is est ablished by t he inf ormat ion t he art if act expresses A: agent responsible f or choosing & organising t he cont ent & st ruct ure of t he art if act D: agent responsible f or physical manif est at ion

• f t he art if act (i.e., capt ures or records it )

RESS ‘94

Our Approach (2)...

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Cont ribut ion f ormat of art if act & int ernal component s PAD agent s:

Art if act

P A D P A D P A D P A D

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RESS ‘94

Our Approach (3)...

I nf er cont ribut ion roles of agent s wrt art if act :

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Represent at ive Aut hor Sponsor Nominal Aut hor True Aut hor Ghost Aut hor Relayer P A D Deviser

RESS ‘94

Our Approach (4)...

I nf er agent commit ment t o art if act

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Who t o involve/ inf orm in queries/ changes: True Aut hor:

P hysical appearance Ant icipat ed/ realised ef f ect St ruct ural f orm Semant ic cont ent P hysical appearance Ant icipat ed/ realised ef f ect St ruct ural f orm Semant ic cont ent P hysical appearance Ant icipat ed/ realised ef f ect St ruct ural f orm Semant ic cont ent

Deviser: Relayer:

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RESS ‘94

Our Approach (5)...

(see chpt . 4) xy xyz req abc req abc elaborat e ref er copy I nf er more about t ypes/ degrees of commit ment Qualif y PAD st at us:

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RESS ‘94

Summarising...

Tracing required det ails about reqs elicit at ion process - Hinders reqs product ion & ref inement Fine/ rapid locat ion of personnel t o perf orm act ivit ies & address def ect s

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Cont ribut ion st ruct ures: Pot ent ial f or cont inuous reqs (re)-def init ion & (re)-assessment Problem:

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RESS ‘94

Quest ions...

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What elicit at ion det ails t ypically get document ed:

• How, when, why used/ by whom?

Which t echniques/ t ools couple det ails of elicit at ion process wit h end product s? Our approach: Scaleable? Dist inguishable? How ext ract , couple & use cont ribut or det ails? How current ly account f or dif f erent capacit ies in which RE part icipant s provide inf o? Now over t o you...