An i*-based Reengineering Framework for Requirements Engineering

Avui en dia, els sistemes d'informació són un actiu clau en les organitzacions i sovint els proporcionen un avantatges competitiu. Per a que això segueixi així, han de ser mantinguts i evolucionats d'acord amb els objectius estratègics de la organització. Aquesta evolució inclou els requeriments del sistema d'informació, la tecnologia emprada i els processos suportats. L'impacte dels canvis pot anar des de petites modificacions al desenvolupament d'un nou sistema d'informació i, per aquest motiu, l'evolució dels sistemes d'informació s'analitza durant la fase de requeriments, on es possible avaluar-ne la magnitud utilitzant menys recursos. Des d'aquest punt de vista, els mètodes de l'enginyeria de requeriments i els de la reenginyeria de processos sovint comparteixen els mateixos objectius i es pot considerar que la reenginyeria de processos es adequada tant per al desenvolupament com per al manteniment dels sistemes d'informació. El llenguatge i* està orientat a objectius i permet modelar els sistemes d'informació en termes d'actors i dependencies entre ells. El llenguatge i* s'utilitza en l'enginyeria de requeriments i en la reenginyeria de processos de negoci, però no existeixen gaires propostes comunes a ambdues disciplines. Amb l'objectiu d'utilitzar el llenguatge i* en la reenginyeria de processos, s'ha definit PRiM, un mètode basat en i* per a la reenginyeria de processos (Proces Reenginieering i*-based Method). PRiM assumeix que ja existeix un procés que s'utilitzarà com a punt de partida per l'especificació o l'evolució del nou sistema d'informació. El mètode PRiM consta de sis fases: 1) l'anàlisi dels processos i dels sistemes d'informació actuals, 2) la construcció del model i*, 3) la reenginyeria dels processos actuals, 4) la generació de models i* representant les diferents alternatives, 5) l'avaluació de les alternatives utilitzant mètriques estructurals i 6) l'especificació del nou sistema d'informació a partir del model i* escollit. En les sis fases de PRiM, s'utilitzen diferents mètodes i tècniques algunes creades expressament pel mètode i d'altres provinents de l'enginyeria de requeriments i la reenginyeria de processos. Tot i això, hi ha altres mètodes i tècniques que poden ser utilitzades enlloc d'aquestes i que poden ser mes convenients quan les condicions d'aplicació del mètode canvien. Per tal de permetre la selecció i inclusió d'altres tècniques, es proposa l'aplicació de l'enginyeria de mètodes (Method Engineering). Aquesta disciplina permet construir nous mètodes a partir de parts de mètodes ja existents, i s'ha utilitzat per definir un mètode marc per a la reenginyeria anomenat ReeF (Reengineering Framework). A ReeF, les sis fases de PRiM es presenten de forma genèrica per tal de permetre la selecció de la tècnica més apropiada per cada una de les fases, a partir de l'experiència de l'usuari com dels seus coneixements de l'aplicació. Com a exemple d'aplicació de ReeF, s'ha definit el mètode SARiM.Les contribucions principals de la tesis son dues. En primer lloc, els dos mètodes basats en i* definits (PRiM per a la reenginyeria de processos, i SARiM, per a la reenginyeria d'arquitectures software). En segon lloc, les diferents tècniques i* definides en PRiM i que poden ser utilitzades per construir models i*, generar alternatives i avaluar-les amb mètriques estructurals. Aquestes tècniques i mètodes s'han obtingut a partir de l'estudi de l'estat de l'art i s'han validat en diferents casos d'estudi formatius i en un cas d'estudi industrial. Com a suport, s'han desenvolupat dues eines: 1) REDEPEND-REACT, que permet la modelització gràfica de models i*, la generació d'alternatives i la definició de mètriques estructurals, i 2) J-PRiM, que dóna suport a les fases de PRiM mitjançant el tractament textual dels models i*.Information Systems are a crucial asset of the organizations and can provide competitive advantages to them. However, once the Information System is built, it has to be maintained and evolved, which includes changes on the requirements, the technology used, or the business processes supported. All these changes are diverse in nature and may require different treatments according to their impact, ranging from small improvements to the deployment of a new Information System. In both situations, changes are addressed at the requirements level, where decisions are analysed involving less resources. Because Requirements Engineering and Business Process Reengineering methods share common activities, and the design of the Information System with the business strategy has to be maintained during its evolution, a Business Process Reengineering approach is adequate for addressing Information Systems Development when there is an existing Information System to be used as starting point. The i* framework is a well-consolidated goal-oriented approach that allows to model Information Systems in a graphical way, in terms of actors and dependencies among them. The i* framework addresses Requirements Engineering and Business Process Reengineering but none of the i*-based existing approaches provides a complete framework for reengineering. In order to explore the applicability of i* for a reengineering framework, we have defined PRiM: a Process Reengineering i* Method, which assumes that there is an existing process that is the basis for the specification of the new Information System. PRiM is a six-phase method that combines techniques from the fields of Business Process Reengineering and Requirements Engineering and defines new techniques when needed. As a result PRiM addresses: 1) the analysis of the current process using socio-technical analysis techniques; 2) the construction of the i* model by differentiating the operationalization of the process form the strategic intentionality behind it; 3) the reengineering of the current process based on its analysis for improvements using goal acquisition techniques; 4) the generation of alternatives based on heuristics and patterns; 5) the evaluation of alternatives by defining structural metrics; and, 6) the specification of the new Information System from the selected i* model.There are several techniques from the Requirements Engineering and Business Process Reengineering fields, that can be used instead the ones selected in PRiM. Therefore, in order to not enforce the application of a certain technique we propose a more generic framework where to use and combine them. Method Engineering is the discipline that constructs new methods from parts of existing ones and, so, it is the approach adopted to define ReeF: a Reengineering Framework. In ReeF the six phases of PRiM are abstracted and generalized in order to allow selecting the most appropriate techniques for each of the phases, depending on the user expertise and the domain of application. As an example of the applicability of ReeF, the new method SARiM is defined. The main contributions of this work are twofold. On the one hand, two i*-based methods are defined: the PRiM method, which addresses process reengineering, and SARiM, which addresses software architecture reengineering. On the other hand, we provide several i*-based techniques to be used for constructing i* models, generating alternatives, and evaluating them using Structural Metrics. These methods and techniques are based on exhaustive review of existing work and their validation is done by means of several formative case studies and an industrial case study. Tool support has been developed for the approach: REDEPEND-REACT supporting the graphical modelling of i*, the generation of alternatives and the definition of Structural Metrics; and J-PRiM supporting all the phases of the PRiM method using a textual visualization of the i* models

Formal and quantitative approach to non-functional requirements modeling and assessment in software engineering

In the software market place, in which functionally equivalent products compete for the same customer, Non Functional Requirements (NFRs) become more important in distinguishing between the competing products. However, in practice, NFRs receive little attention relative to Functional Requirements (FRs). This is mainly because of the nature of these requirements which poses a challenge when taking the choice of treating them earlier in the software development. NFRs are subjective, relative and they become scattered among multiple modules when they are mapped from the requirements domain to the solution space. Furthermore, NFRs can often interact, in the sense that attempts to achieve one NFR can help or hinder the achievement of other NFRs at particular software functionality. Such an interaction creates an extensive network of interdependencies and tradeoffs among NFRs which is not easy to trace or estimate. This thesis contributes towards achieving the goal of managing the attainable scope and the changes of NFRs. The thesis proposes and empirically evaluates a formal and quantitative approach to modeling and assessing NFRs. Central to such an approach is the implementation of the proposed NFRs Ontology for capturing and structuring the knowledge on the software requirements (FRs and NFRs), their refinements, and their interdependencies. In this thesis, we also propose a change management mechanism for tracing the impact of NFRs on the other constructs in the ontology and vice-versa. We provide a traceability mechanism using Datalog expressions to implement queries on the relational model-based representation for the ontology. An alternative implementation view using XML and XQuery is provided as well. In addition, we propose a novel approach for the early requirements-based effort estimation, based on NFRs Ontology. The effort estimation approach complementarily uses one standard functional size measurement model, namely COSMIC, and a linear regression techniqu

Feature-based generation of pervasive systems architectures utilizing software product line concepts

As the need for pervasive systems tends to increase and to dominate the computing discipline, software engineering approaches must evolve at a similar pace to facilitate the construction of such systems in an efficient manner. In this thesis, we provide a vision of a framework that will help in the construction of software product lines for pervasive systems by devising an approach to automatically generate architectures for this domain. Using this framework, designers of pervasive systems will be able to select a set of desired system features, and the framework will automatically generate architectures that support the presence of these features. Our approach will not compromise the quality of the architecture especially as we have verified that by comparing the generated architectures to those manually designed by human architects. As an initial step, and in order to determine the most commonly required features that comprise the widely most known pervasive systems, we surveyed more than fifty existing architectures for pervasive systems in various domains. We captured the most essential features along with the commonalities and variabilities between them. The features were categorized according to the domain and the environment that they target. Those categories are: General pervasive systems, domain-specific, privacy, bridging, fault-tolerance and context-awareness. We coupled the identified features with well-designed components, and connected the components based on the initial features selected by a system designer to generate an architecture. We evaluated our generated architectures against architectures designed by human architects. When metrics such as coupling, cohesion, complexity, reusability, adaptability, modularity, modifiability, packing density, and average interaction density were used to test our framework, our generated architectures were found comparable, if not better than the human generated architectures

A reactive architecture for cloud-based system engineering

PhD ThesisSoftware system engineering is increasingly practised over globally distributed locations. Such a practise is termed as Global Software Development (GSD). GSD has become a business necessity mainly because of the scarcity of resources, cost, and the need to locate development closer to the customers. GSD is highly dependent on requirements management, but system requirements continuously change. Poorly managed change in requirements affects the overall cost, schedule and quality of GSD projects. It is particularly challenging to manage and trace such changes, and hence we require a rigorous requirement change management (RCM) process. RCM is not trivial in collocated software development; and with the presence of geographical, cultural, social and temporal factors, it makes RCM profoundly difficult for GSD. Existing RCM methods do not take into consideration these issues faced in GSD. Considering the state-of-the-art in RCM, design and analysis of architecture, and cloud accountability, this work contributes: 1. an alternative and novel mechanism for effective information and knowledge-sharing towards RCM and traceability. 2. a novel methodology for the design and analysis of small-to-medium size cloud-based systems, with a particular focus on the trade-off of quality attributes. 3. a dependable framework that facilitates the RCM and traceability method for cloud-based system engineering. 4. a novel methodology for assuring cloud accountability in terms of dependability. 5. a cloud-based framework to facilitate the cloud accountability methodology. The results show a traceable RCM linkage between system engineering processes and stakeholder requirements for cloud-based GSD projects, which is better than existing approaches. Also, the results show an improved dependability assurance of systems interfacing with the unpredictable cloud environment. We reach the conclusion that RCM with a clear focus on traceability, which is then facilitated by a dependable framework, improves the chance of developing a cloud-based GSD project successfully

ICSEA 2021: the sixteenth international conference on software engineering advances

The Sixteenth International Conference on Software Engineering Advances (ICSEA 2021), held on October 3 - 7, 2021 in Barcelona, Spain, continued a series of events covering a broad spectrum of software-related topics. The conference covered fundamentals on designing, implementing, testing, validating and maintaining various kinds of software. The tracks treated the topics from theory to practice, in terms of methodologies, design, implementation, testing, use cases, tools, and lessons learnt. The conference topics covered classical and advanced methodologies, open source, agile software, as well as software deployment and software economics and education. The conference had the following tracks: Advances in fundamentals for software development Advanced mechanisms for software development Advanced design tools for developing software Software engineering for service computing (SOA and Cloud) Advanced facilities for accessing software Software performance Software security, privacy, safeness Advances in software testing Specialized software advanced applications Web Accessibility Open source software Agile and Lean approaches in software engineering Software deployment and maintenance Software engineering techniques, metrics, and formalisms Software economics, adoption, and education Business technology Improving productivity in research on software engineering Trends and achievements Similar to the previous edition, this event continued to be very competitive in its selection process and very well perceived by the international software engineering community. As such, it is attracting excellent contributions and active participation from all over the world. We were very pleased to receive a large amount of top quality contributions. We take here the opportunity to warmly thank all the members of the ICSEA 2021 technical program committee as well as the numerous reviewers. The creation of such a broad and high quality conference program would not have been possible without their involvement. We also kindly thank all the authors that dedicated much of their time and efforts to contribute to the ICSEA 2021. We truly believe that thanks to all these efforts, the final conference program consists of top quality contributions. This event could also not have been a reality without the support of many individuals, organizations and sponsors. We also gratefully thank the members of the ICSEA 2021 organizing committee for their help in handling the logistics and for their work that is making this professional meeting a success. We hope the ICSEA 2021 was a successful international forum for the exchange of ideas and results between academia and industry and to promote further progress in software engineering research

Modelling Event-Based Interactions in Component-Based Architectures for Quantitative System Evaluation

This dissertation thesis presents an approach enabling the modelling and quality-of-service prediction of event-based systems at the architecture-level. Applying a two-step model refinement transformation, the approach integrates platform-specific performance influences of the underlying middleware while enabling the use of different existing analytical and simulation-based prediction techniques

Certifications of Critical Systems – The CECRIS Experience

In recent years, a considerable amount of effort has been devoted, both in industry and academia, to the development, validation and verification of critical systems, i.e. those systems whose malfunctions or failures reach a critical level both in terms of risks to human life as well as having a large economic impact.Certifications of Critical Systems – The CECRIS Experience documents the main insights on Cost Effective Verification and Validation processes that were gained during work in the European Research Project CECRIS (acronym for Certification of Critical Systems). The objective of the research was to tackle the challenges of certification by focusing on those aspects that turn out to be more difficult/important for current and future critical systems industry: the effective use of methodologies, processes and tools.The CECRIS project took a step forward in the growing field of development, verification and validation and certification of critical systems. It focused on the more difficult/important aspects of critical system development, verification and validation and certification process. Starting from both the scientific and industrial state of the art methodologies for system development and the impact of their usage on the verification and validation and certification of critical systems, the project aimed at developing strategies and techniques supported by automatic or semi-automatic tools and methods for these activities, setting guidelines to support engineers during the planning of the verification and validation phases

An open source software selection process and a case study

In this study, I design an empirical open source software selection process, which reuses some ideas from Commercial Off-the-Shelf selection methods and addresses the characteristics of the open source software. Basically, it consists of three basic steps: identification, screening and evaluation. The identification step is to find all possible alternatives to open source software that can meet the high level requirements. The next step is screening, in which the refined requirements are applied to filter the alternatives. The evaluation step is based on the Analytic Hierarchy Process, in which the alternatives are inspected from functional suitability, source code, support strength and popularity. In more detail, under functionality suitability criterion, alternatives to open source software are evaluated in viewing of how much functionality can fit in with the functional user requirements. The source code of the alternatives is evaluated from six criteria: programming language, code size, code comment, code intra-module complexity and code inter-module complexity. The evaluation of support strength depends on the evaluation of field support and support resources. The field support includes commercial support and community support. The community support specifically refers to the direct responses from the community to the support requests. Aside from field support, open source software projects also provide various support-related resources such as, documents, wiki, blog, etc. To determine the popularity of the alternatives, I evaluate them from software use, development participation and web popularity. In the case study, I utilize the process to select the best open source unified modeling language tool from the ten alternatives for the software development process. After the screening phase, the four competitive alternatives, BOUML, ArgoUML, UMLet and Violet, are evaluated from functionality, source code, support strength and popularity criteria. The evaluation result indicates that ArgoUML is the best tool for the requirement. The case study demonstrates the effectiveness of the selection process. Various important attributes of open source software are taken into consideration systematically and the final decision is reached based on comprehensive investigation and analysis. The process provides an operable solution to the open source selection problem in practice