Support for Requirement Traceability: The Tropos Case

1Universidade Federal de Pernambuco - Centro de Informatica

Support for Requirement Traceability: The Tropos Case

Rosa Pinto, Carla Silva, Jaelson Castro

{rccp, ctlls, jbc}@cin.ufpe.br

Outline Motivation Requirements traceability Meta-

model Tropos framework The Requirements Traceability

Process Case Study Conclusions

Motivation In complex systems there are quite

complex web of relationships

Methodologies supporting requirement traceability can develop higher quality software with fewer costs

Agent Oriented Development Software

Requirements Traceability Requirements traceability refers to

the ability to describe and follow the life of a requirement, in both a forwards and backwards direction (i.e., from its origins, through its development and specification, to its subsequent deployment and use, and through all periods of on-going refinement and iteration in any of these phases) [Pinheiro 2003]

Our Proposal

Agents

Tracing

Tropos

Requirements Traceability Reference Model [Toranzo 2002 e 2005]

Requirement Management sub-model

Design sub-model Rational model


E x t e r n a l

Organizational Objectives

0..n

1..n

0..n

1..n

<<resource>>

0..n 10..n 1

S y s t e m O b j e c t i v e s

0..n1..n0..n1..n << resource>>0..n 10..n 1

C o n s t r a i n t

Change Purpose

0..n

0..n

0..n

0..n

<<satisfy>>

T a s k

0..n

0..n

0..n

0..n

<<resource>>

0..n0..n 0..n0..n<<resource>>

0..n 10..n 10..n0..n0..n0..n<<resource>>

S t a k e h o l d e r

I n f o r m a t i o n

0..n

1..n

0..n

1..n<<satisfy>>

0..n 0..n0..n

<<resource>>

0..n0..n

0..n

0..n

0..n

<<responsability>>

R e q u i r e m e n t

0..n0..n

0..n0..n

<<resource>>

1..n0..n 1..n0..n

<<resource>>

0..n 10..n 1

0..n0..n 0..n0..n

<<responsability>>

0..n

0..n

0..n

0..n

<<resource>>

Design sub-model

S u b s y s t e m

D i a g r a m

R e q u i r e m e n t 0..n0..n 0..n0..n <<allocated_to>>

T e s t0..n

0..n

0..n

0..n<<resource>>

P r o g r a m

0..n

0..n

0..n

0..n

<< resource>>

0..n

0..n

0..n

0..n<<represents>>

0..n

0..n

0..n

0..n <<resource>>

T a s k

D e s i g n E l e m e n t0..n

1..n

0..n

1..n

<<satisfy>>

Change Purpose0..n 0..n0..n 0..n<<resource>>

S t a k e h o l d e r I n f o r m a t i o n0..n0..n 0..n0..n <<responsability>>

0..n

0..n

0..n <<resource>>

0..n

Rational Model

E x t e r n a l

Organizational Objectives

0..n

1..n

0..n

1..n

<<resource>>

0..n 10..n 1

S y s t e m O b j e c t i v e s

0..n1..n0..n1..n << resource>>0..n 10..n 1

C o n s t r a i n t

Change Purpose

0..n

0..n

0..n

0..n

<<satisfy>>

T a s k

0..n

0..n

0..n

0..n

<<resource>>

0..n0..n 0..n0..n<<resource>>

0..n 10..n 10..n0..n0..n0..n<<resource>>

S t a k e h o l d e r

I n f o r m a t i o n

0..n

1..n

0..n

1..n<<satisfy>>

0..n 0..n0..n

<<resource>>

0..n0..n

0..n

0..n

0..n

<<responsability>>

R e q u i r e m e n t

0..n0..n

0..n0..n

<<resource>>

1..n0..n 1..n0..n

<<resource>>

0..n 10..n 1

0..n0..n 0..n0..n

<<responsability>>

0..n

0..n

0..n

0..n

<<resource>>

Tropos Framework Concepts and Phases

Early

requirements Late

requirements

Architectural

design Detaile

d

designEarly

requirements Late

requirements

Architectural

design Detaile

d

design

Requirements-driven Software developmentRequirements-driven Software development

DEPENDUMDEPENDER DEPENDEE


Estudo de Caso: Media Shop

Requirements Traceability Process Stages of process

1. Information Gathering (IG): identify the information to be traced

2. Information Structuring (ST) used to: achieve the proper structuring of the information

identified before defined the set of valid values for association

instances

3. Definition of the Traceability Matrixes (TM): guide the construction of the appropriate traceability

matrixes

Requirements Traceability Process Stage 1. Information Gathering (IG)

IG1. Requirement Management sub-model classes from SD diagram of the actor representing the system

Rule 1. Actor which has some dependency relationship with

System actor STAKEHOLDER class


SD Diagram for Medi@ System

STAKEHOLDERS



Rule 2. System actor is dependee of softgoal, resource or task

the dependum REQUIREMENT class


SD Diagram for Medi@ System

STAKEHOLDERS

REQUIREMENTS




Rule 3. System actor is dependee of a goal dependency of the actor representing the organization

The depedum ORGANIZATIONAL OBJECTIVES class


SD Diagrama for Medi@ System

STAKEHOLDERS

REQUIREMENTS

ORGANIZATIONAL OBJECTIVE




Rule 4. System actor is depender of a goal dependency of the actor does not represent the organization

The goal SYSTEM OBJECTIVES class

Organizational Map


STAKEHOLDERS

REQUIREMENTS


SYSTEM OBJECTIVE




Rule 5. System actor is depender of goal, softgoal, resource or task

The dependum EXTERNAL class

Organizational Map

STAKEHOLDERS

REQUIREMENTS


SYSTEM OBJECTIVE

EXTERNAL




IG2. Requirement Management sub-model classes from SR diagram of the actor representing the system

Rule 1. Goal SYSTEM OBJECTIVES class

Rule 2. Task REQUIREMENT class Rule 3. Softgoal REQUIREMENT class Rule 4. Resource REQUIREMENT class

SR Diagrama for Medi@ System

REQUIREMENTS

SYSTEM OBJECTIVE



IG3. Rational model classes from the process for selecting the proper architectural style

Rule 1. SUBJECT class issue on which a decision must be taken

Rule 2. POSITION class alternative solutions for the SUBJECT

Rule 3. ARGUMENT class some criteria used for choosing the proper solution


IG3. Rational model classes from the process for selecting the proper architectural style

Rule 4. ASSUMPTION class facts that must be taken into account for choosing

Rule 5. CONSTRAINT class limitations/restrictions that must be taken into account for deciding the proper solution

Rule 6. DOCUMENT class some information used as reference for choosing the proper solution


IG4. Design Sub-model classes from the architectural design model

Rule 1. Each architectural component SUBSYSTEM class

Requirements Traceability Process Stage 2. Information Structuring (ST)

ST1. to remove classes unnecessary, and to delete instances with the same meaning

ST2. for each pair of associated classes in the reference model, the association should be instantiated

ST3. for each instance created in the ST2, define the set of values assigned to it.

Requirements Traceability Process

Stage 3. Definition of the Traceability Matrixes (TM) Guideline TM1

For each pair of instantiated classes which are associated in a reference model, we can create a traceability matrix.

Guideline TM2 For each created matrix, we have to analyze the

system artifacts which are related to the matrix and fill the association which has been instantiated in a previous stage of the process.

Requirements Traceability Process Stage 3. Definition of the

Traceability Matrixes (TM) Applying TM1 and TM2:

create a traceability matrix to the instances of the <<resource>> association between REQUIREMENTS and ORGANIZATIONAL INFORMATION elements

<H> (High), <M> (Medium) or <L> (Low).


<<resource>>

<<resource>>

1

0..n

0..n

0..n0..n

<<resource>>

0..n1..n

<<satisfy>>0..n

0..n 1

0..n

0..n

<<resource>>

0..n

<<responsability>>

0..n 1

1..n <<resource>>

0..n

0..n

0..n 1

0..n

1..n

0..n

0..n

<<satisfy>>

<<resource>>

1..n

0..n

0..n<<responsability>>

0..n

0..n

<<resource>>

0..n

0..n

<<resource>>

EXTERNAL C O N S T R A I N T

CHANGE PURPOSE

ORGANIZATIONAL INFORMATION

S T A K E H O L D E R

<<resource>>

0..n

I N F O R M A T I O N

0..n

0..n

R E Q U I R E M E N T

SYSTEM OBJECTIVES

T A S K

Case Study

<<resource>>

[ORG1] Happy Customers

[ORG2] Run Shop

[ORG3] Improve Service

[RF1] Browse Catalogue

M M M

[RF2] Keyword Search

M M M

[RF3] Place Order

M M M

[RF4] Process Internet Orders

H H H

Case Study Estimating the impact of a change

If some organizational information is changed, the impact in the system requirements can be analyzed.

Conclusions We outline a process that can be used to extend Tropos

to address requirements traceability.

We intend to develop a complete and usable requirement traceability process for Tropos aiming to ensure the quality improvement of both the methodology and the software developed with it.

Further guidelines for instantiating all the classes of the three reference models (Requirement Management and Design sub-models and Rational model) for each phase of Tropos may be required.

Questions/suggestions ?

Documents

Support for Requirement Traceability: The Tropos Case