1. May 14, 2015 1 May 14, 2015May 14, 2015May 14, 2015 Azusa, CA Sheldon X. Liang Ph. D. Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap

2. May 14, 2015 2 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Abstract Success of software ? How? How to know the purpose ? –Identifying stakeholders –Identifying stakeholders’ needs –Creating documentation for: Analysis Communication Implementation

3. May 14, 2015 3 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap  Introduction  Foundation  Groundwork  Eliciting Req  Modeling & Analysis  Communicating Req  Agreeing Req  Evolving Req  Integrating Req E  RE Roadmap  What is the future?

4. May 14, 2015 4 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Inherent difficulties –Numerous and distributed stakeholders –Vary and conflicting goals –Goals may not be explicit –Difficult to articulate requirements  Introduction

5. May 14, 2015 5 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Definition of Requirement Engineering “ Requirements engineering is the branch of software engineering concerned with the real-world goals for, functions of, and constraints on software systems. It is also concerned with the relationship of these factors to precise specifications of software behavior, and to their evolution over time and across software families. ”  Foundation

6. May 14, 2015 6 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap What's good about the definition ? –Highlights the importance of real-world goals –Precise specification of: Analyzing – requirements Validating – what stakeholders need Defining – what designers have to build Verifying – they have done so correctly Evolution – capable to cope with the changes What's ambiguous in the definition ? –Main focus is on software engineering  Foundation

7. May 14, 2015 7 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap The context in which RE takes place is usually human activity system and the problem owner are people. Techniques for eliciting and modeling, drawn on cognitive and social sciences: –Cognitive Psychology –Anthropology –Sociology –Linguistics  Foundation

8. May 14, 2015 8 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap RE is often the fore-end activity in the software system development process RE plays an important role in the management of change in software development RE processes depend on the type of product Groundwork mean the assessment of project’s feasibility and associated risks  Groundwork

9. May 14, 2015 9 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Requirements to Elicit –Boundaries Identify the high level boundaries of the system Stakeholders and Use Cases depend on boundaries –Stakeholders Customer or Clients Developers Users –Goals Eliciting High level goals early in development –Tasks When it is difficult to articulate user requirements  Eliciting Req

10. May 14, 2015 10 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Elicitation Techniques –Traditional Techniques Questionnaires and Surveys Interviews Analysis of existing documentation –Group Elicitation Group brainstorming sessions RAD (Rapid Application Development) JAD (Joint Application Design) –Prototyping Where there is great deal of uncertainty Early feedback from stakeholders is needed  Eliciting Req

11. May 14, 2015 11 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Elicitation Techniques –Model-Driven Goal Based Methods – KAOS & I Scenario Based Methods - CREWS –Cognitive Protocol Analysis Laddering Card Sorting Repertory Grids –Contextual Alternative to Tradition and Cognitive techniques Ethnographic Technique– Participant Observation  Eliciting Req

12. May 14, 2015 12 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap “The construction of abstract descriptions that are amenable to interpretation ” Enterprise Modeling –Understanding organization's structure –Business rules –Goals, tasks and responsibilities –Data Data Modeling –Understand, manipulate and manage large volume of information –How to represent real world phenomenon into system information  Modeling & Analysis

13. May 14, 2015 13 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Behavioral Modeling –Dynamic or Functional behavior of stakeholders and system, both existing and required Domain Modeling –Abstract description of the world in which the system will operate –Requirements reuse within a domain Modeling Non-Functional Requirements –Difficult to express in a measurable way –Difficult to analyze –Properties of a system as a whole  Modeling & Analysis

14. May 14, 2015 14 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Analyzing Requirements Models –Requirements Animation –Automated Reasoning –Analogical and Case-based Reasoning –Knowledge based Critiquing –Consistency Checking  Modeling & Analysis

15. May 14, 2015 15 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Requirement Management “The ability, not only to write requirements but also to do so in a form that is readable and traceable by many, in order to manage their evolution over time ” Requirement Traceability (RT) “The ability to describe and follow life of a requirement in both forwards and backwards direction ”  Communicating Req

16. May 14, 2015 16 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Maintaining agreement with the stakeholders can be a problem Validation “Validation is the process of establishing that the requirements and models elicited provide an accurate account of stakeholder requirements ” Validation is difficult for two reasons: –Question of truth and what is knowable –Reaching agreement among different stakeholders  Agreeing Req

17. May 14, 2015 17 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Adding requirements –Changing stakeholder needs –Missed in initial analysis Requirement Scrubbing – Removing requirements –Usually only during development, to forestall cost and schedule overruns Manage inconsistency in requirements Managing changing requirements –Continued requirement elicitation –Evaluation of Risk –Evaluation of systems in the environment  Evolving Req

18. May 14, 2015 18 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Product Family –Increasingly important form of development activity –Range of software product that share similar requirements and architectural characteristics, yet differ in certain key requirements –Research issue : Identifying the core requirements for the architectures that are: Stable in the presence of change Flexible enough to be customized and adapted to changing requirements  Evolving Req

19. May 14, 2015 19 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Different approaches to manage and integrate RE activities: –Problem Frames –Viewpoints Automated tools: –DOORS –Requisite Pro –Cradle  Integrating RE

20. May 14, 2015 20 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap Three radical ideas –Modeling and analysis cannot be performed adequately in isolation from the organizational and social context in which the new system will have to operate –RE should not focus on specifying the functionality of a new system, but instead should concentrate on modeling indicative and optative properties of the environment –Attempt to build consistent and complete requirement models is futile.  RE Roadmap

21. May 14, 2015 21 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap New techniques for formally modeling and analyzing properties of the environment Richer model for capturing and analyzing non- functional requirements Bridging the gap between requirements elicitation apporaches. Better understanding of software architectural choices Reuse of requirement models Multidisciplinary training of requirements practitioners  What’s the Future

22. May 14, 2015 22 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap

23. May 14, 2015 23 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap

24. May 14, 2015 24 Software Engineering in CS at APU Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ CS 524 Requirement Engineering: A Roadmap

25. Thank you very much! Questions? May 14, 2015 25 Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/http://www.apu.edu/clas/computerscience/ Software Engineering in CS at APU CS 524 Requirement Engineering: A Roadmap