Software Requirements

1. Software Requirements By Jane Cleland-Huang Presentation by Donovan Faustino

2. Introduction • Requirements Engineering - process of eliciting, analyzing, validating, and managing requirements • IEEE standards such as IEEE Std 830-1998 provide guidelines for recommended practices

3. Requirements • Defining Requirements • – property of the system or a constraint placed either upon the product itself or upon the process by which the system is created. Formally IEE Std 610.12.1990 – 1) A condition or capability needed by a user to solve a problem or achieve an objective • 2) A condition or capability that must be met or possessed by a system or system component to satisfy a contract, standard, specification, or other formally imposed documents. • 3) A documented representation of a condition or capability as in (1) or (2).

4. Phases of Requirements • Elicitation • Analysis • Specification • Management • Validation

5. Elicitation • proactively working with stakeholders to discover their needs, identify and negotiate potential conflicts, and establish a clear scope and boundaries for the project

6. Elicitation(cont) • Understanding the Problem and Its Domain • Making the business case • current trends have organizations are no longer willing to invest in IT projects unless those projects return clear value to the business • From a requirements perspective, these include a lack of clear purpose for the product, insufficient stakeholder involvement, lack of agreement between stakeholders, rapidly changing the requirements, goldplating(adding additional and unnecessary features), poor change management, and lack of analysis of the requirements

7. Elicitation(cont) • Elicitation techniques • Collaborative sessions • Interviewing techniques • Questionaires • Ethnography • Protyping • Documentation • Modeling • Roleplaying • Checklists of NFRs

8. Elicitation • Conflict Identification and Negotiation

9. Analysis • a deeper understanding of the product and its interactions, identify requirements, define high-level architectural design, allocating req to architectural components, and identify additional conflicts that merge through considering architectural implementations and negotiating agreements between stakeholders

10. Analysis(cont) • Conceptual Modeling • ML is very well known. • IEEE Std 1320.1, IDEF0 for functional modeling and IEEE Std 1320.2 IDEF1 X97 for information modeling. • Architectural Design and Requirement Allocation • Architectural quality is measured by its ability to fulfill the stated requirements

11. Specification • documents that capture the system and software req. in order to support their systematic review, evaluation, and approval. Document that describes the system to be developed in a format that can be reviewed, evaluated and approved in a systematic way.

12. Specification(cont) • Qualities of an Individual Requirement • Concise • Correct • Nonambiguous • Feasible • Verifiable

13. Specification (cont) • Qualities of the Set of Requirements • Realistic • Concise • Complete • Consistent

14. Validation • goes through the other four activities. Ensure the system meets stakeholders requirements through activities such as formal and informal reviews

15. Validation(cont) • Types of validation • Reviews • Prototyping • Model validation • Acceptance Tests

16. Management • starts from the moment the first req is elicited and ends only when the system is finally decommissioned. requirement management includes software configuration management, traceability, impact analysis, and version control

17. Management(cont) • Requirements traceability • Ability to describe and follow the life of a requirement, in both a forward and backward direction. • Change Requests • Managed systematically • Requirements attributes

18. Conclusion • Traditional Method • Agile Methods

19. My own opinion

20. Validation