Support for Requirement Traceability: The Tropos Case

1. Support for Requirement Traceability: The Tropos Case Rosa Pinto, Carla Silva, Jaelson Castro {rccp, ctlls, jbc}@cin.ufpe.br Universidade Federal de Pernambuco - Centro de Informatica

2. Outline • Motivation • Requirements traceability Meta-model • Tropos framework • The Requirements Traceability Process • Case Study • Conclusions

3. 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

4. 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]

5. Tracing Agents Tropos Our Proposal

6. Requirements Traceability Reference Model • [Toranzo 2002 e 2005] • Requirement Management sub-model • Design sub-model • Rational model

7. Requirement Management sub-model

8. Design sub-model

9. Rational Model

10. Requirements-driven Software development Detailed design Detailed design Architectural design Architectural design Early requirements Early requirements Late requirements Late requirements DEPENDER DEPENDUM DEPENDEE Tropos Framework • Concepts and Phases

11. Estudo de Caso: Media Shop Universidade Federal de Pernambuco - Centro de Informatica

12. 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

13. 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

14. SD Diagram for Medi@ System STAKEHOLDERS Universidade Federal de Pernambuco - Centro de Informatica

15. Requirements Traceability Process • Stage 1. Information Gathering (IG) • IG1. Requirement Management sub-model classes from SD diagram of the actor representing the system • Rule 2. System actor is dependee of softgoal, resource or task • the dependum  REQUIREMENT class

16. DEPENDER DEPENDUM DEPENDEE SD Diagram for Medi@ System STAKEHOLDERS REQUIREMENTS Universidade Federal de Pernambuco - Centro de Informatica

17. Requirements Traceability Process • Stage 1. Information Gathering (IG) • IG1. Requirement Management sub-model classes from SD diagram of the actor representing the system • Rule 3. System actor is dependee of a goal dependency of the actor representing the organization • The depedum  ORGANIZATIONAL OBJECTIVES class

18. DEPENDER DEPENDUM DEPENDEE SD Diagrama for Medi@ System STAKEHOLDERS REQUIREMENTS ORGANIZATIONAL OBJECTIVE Universidade Federal de Pernambuco - Centro de Informatica

19. Requirements Traceability Process • Stage 1. Information Gathering (IG) • IG1. Requirement Management sub-model classes from SD diagram of the actor representing the system • Rule 4. System actor is depender of a goal dependency of the actor does not represent the organization • The goal  SYSTEM OBJECTIVES class

20. DEPENDER DEPENDUM DEPENDEE SD Diagrama for Medi@ System Organizational Map STAKEHOLDERS REQUIREMENTS ORGANIZATIONAL OBJECTIVE SYSTEM OBJECTIVE

21. Requirements Traceability Process • Stage 1. Information Gathering (IG) • IG1. Requirement Management sub-model classes from SD diagram of the actor representing the system • Rule 5. System actor is depender of goal, softgoal, resource or task • The dependum  EXTERNAL class

22. DEPENDER DEPENDUM DEPENDEE SD Diagrama for Medi@ System Organizational Map STAKEHOLDERS REQUIREMENTS ORGANIZATIONAL OBJECTIVE SYSTEM OBJECTIVE EXTERNAL

23. Requirements Traceability Process • Stage 1. Information Gathering (IG) • 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

24. DEPENDER DEPENDUM DEPENDEE SR Diagrama for Medi@ System SYSTEM OBJECTIVE REQUIREMENTS

25. Requirements Traceability Process • Stage 1. Information Gathering (IG) • 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

26. Requirements Traceability Process • Stage 1. Information Gathering (IG) • 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

27. Requirements Traceability Process • Stage 1. Information Gathering (IG) • IG4. Design Sub-model classes from the architectural design model • Rule 1. Each architectural component  SUBSYSTEM class

28. 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.

29. 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.

30. 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).

31. Requirement Management sub-model C O N S T R A I N T EXTERNAL 0..n <<resource>> <<resource>> 0..n <<satisfy>> 1..n 0..n 1 1..n 0..n 0..n ORGANIZATIONAL INFORMATION I N F O R M A T I O N 0..n 0..n 0..n <<satisfy>> 0..n 0..n <<resource>> <<resource>> 1 0..n 1..n SYSTEM OBJECTIVES <<resource>> 0..n CHANGE PURPOSE <<resource>> 0..n 0..n 0..n <<resource>> 0..n 0..n 1 0..n T A S K 0..n <<resource>> 1..n <<resource>> 0..n 0..n 1 0..n R E Q U I R E M E N T 0..n 0..n <<responsability>> <<responsability>> S T A K E H O L D E R 0..n 0..n

32. Case Study

33. Case Study • Estimating the impact of a change • If some organizational information is changed, the impact in the system requirements can be analyzed.

34. 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.

35. Questions/suggestions ?