Dealing with non-functional requirements in model-driven development

The impact of non-functional requirements (NFRs) over software systems has been widely documented. Consequently, cost-effective software production method shall provide means to integrate this type of requirements into the development process. In this vision paper we analyze this assumption over a particular type of software production paradigm: model-driven development (MDD). We report first the current state of MDD approaches with respect to NFRs and remark that, in general, NFRs are not addressed in MDD methods and processes, and we discuss the effects of this situation. Next, we outline a general framework that integrates NFRs into the core of the MDD process and provide a detailed comparison among all the MDD approaches considered. Last, we identify some research issues related to this framework.Preprin

Assisting software architects in architectural decision-making using Quark

Non-Functional Requirements (NFRs) and constraints are among the principal drivers of architectural decision-making. NFRs are improved or damaged by architectural decisions (ADs), while constraints directly include or exclude parts of the architecture (e.g., logical components or technologies). We may determine the impact of an AD, or which parts of the architecture are affected by a constraint, but at the end it is hard to know if we are respecting the NFRs and the imposed constraints with all the ADs made. In the usual approach, architects use their own experience to produce software architectures that comply with the NFRs and imposed constraints, but at the end, especially for crucial decisions, the architect has to deal with complex trade-offs between NFRs and juggle with possible incompatibilities raised by the imposed constraints. In this paper we present Quark, a method to assist software architects in architectural decision-making, and the conceptualization of the relationship between NFRs and ADs defined in Arteon, an ontology to represent and manage architectural knowledge. Finally, we provide an overview of the Quark and Arteon implementation, the ArchiTech tool.Peer ReviewedPostprint (published version

Development of service-oriented architectures using model-driven development : a mapping study

Context: Model-Driven Development (MDD) and Service-Oriented Architecture (SOA) are two challenging research areas in software engineering. MDD is about improving software development whilst SOA is a service-based conceptual development style, therefore investigating the available proposals in the literature to use MDD when developing SOA may be insightful. However, no studies have been found with this purpose. Objective: This work aims at assessing the state of the art in MDD for SOA systems. It mainly focuses on: what are the characteristics of MDD approaches that support SOA; what types of SOA are supported; how do they handle non-functional requirements. Method: We conducted a mapping study following a rigorous protocol. We identified the representative set of venues that should be included in the study. We applied a search string over the set of selected venues. As result, 129 papers were selected and analysed (both frequency analysis and correlation analysis) with respect to the defined classification criteria derived from the research questions. Threats to validity were identified and mitigated whenever possible. Results: The analysis allows us to answer the research questions. We highlight: (1) predominance of papers from Europe and written by researchers only; (2) predominance of top-down transformation in software development activities; (3) inexistence of consolidated methods; (4) significant percentage of works without tool support; (5) SOA systems and service compositions more targeted than single services and SOA enterprise systems; (6) limited use of metamodels; (7) very limited use of NFRs; and (8) limited application in real cases. Conclusion: This mapping study does not just provide the state of the art in the topic, but also identifies several issues that deserve investigation in the future, for instance the need of methods for activities other than software development (e.g., migration) or the need of conducting more real case studies.Peer ReviewedPostprint (author's final draft

Contribución a la estimulación del uso de soluciones Cloud Computing: Diseño de un intermediador de servicios Cloud para fomentar el uso de ecosistemas distribuidos digitales confiables, interoperables y de acuerdo a la legalidad. Aplicación en entornos multi-cloud.

184 p.El objetivo del trabajo de investigación presentado en esta tesis es facilitar a los desarrolladores y operadores de aplicaciones desplegadas en múltiples Nubes el descubrimiento y la gestión de los diferentes servicios de Computación, soportando su reutilización y combinación, para generar una red de servicios interoperables, que cumplen con las leyes y cuyos acuerdos de nivel de servicio pueden ser evaluados de manera continua. Una de las contribuciones de esta tesis es el diseño y desarrollo de un bróker de servicios de Computación llamado ACSmI (Advanced Cloud Services meta-Intermediator). ACSmI permite evaluar el cumplimiento de los acuerdos de nivel de servicio incluyendo la legislación. ACSmI también proporciona una capa de abstracción intermedia para los servicios de Computación donde los desarrolladores pueden acceder fácilmente a un catálogo de servicios acreditados y compatibles con los requisitos no funcionales establecidos.Además, este trabajo de investigación propone la caracterización de las aplicaciones nativas multiNube y el concepto de "DevOps extendido" especialmente pensado para este tipo de aplicaciones. El concepto "DevOps extendido" pretende resolver algunos de los problemas actuales del diseño, desarrollo, implementación y adaptación de aplicaciones multiNube, proporcionando un enfoque DevOps novedoso y extendido para la adaptación de las prácticas actuales de DevOps al paradigma multiNube

Validating a model-driven software architecture evaluation and improvement method: A family of experiments

Context: Software architectures should be evaluated during the early stages of software development in order to verify whether the non-functional requirements (NFRs) of the product can be fulfilled. This activity is even more crucial in software product line (SPL) development, since it is also necessary to identify whether the NFRs of a particular product can be achieved by exercising the variation mechanisms provided by the product line architecture or whether additional transformations are required. These issues have motivated us to propose QuaDAI, a method for the derivation, evaluation and improvement of software architectures in model-driven SPL development. Objective: We present in this paper the results of a family of four experiments carried out to empirically validate the evaluation and improvement strategy of QuaDAI. Method: The family of experiments was carried out by 92 participants: Computer Science Master s and undergraduate students from Spain and Italy. The goal was to compare the effectiveness, efficiency, perceived ease of use, perceived usefulness and intention to use with regard to participants using the evaluation and improvement strategy of QuaDAI as opposed to the Architecture Tradeoff Analysis Method (ATAM). Results: The main result was that the participants produced their best results when applying QuaDAI, signifying that the participants obtained architectures with better values for the NFRs faster, and that they found the method easier to use, more useful and more likely to be used. The results of the meta-analysis carried out to aggregate the results obtained in the individual experiments also confirmed these results. Conclusions: The results support the hypothesis that QuaDAI would achieve better results than ATAM in the experiments and that QuaDAI can be considered as a promising approach with which to perform architectural evaluations that occur after the product architecture derivation in model-driven SPL development processes when carried out by novice software evaluators.The authors would like to thank all the participants in the experiments for their selfless involvement in this research. This research is supported by the MULTIPLE Project (MICINN TIN2009-13838) and the ValI+D Program (ACIF/2011/235).González Huerta, J.; Insfrán Pelozo, CE.; Abrahao Gonzales, SM.; Scanniello, G. (2015). Validating a model-driven software architecture evaluation and improvement method: A family of experiments. Information and Software Technology. 57:405-429. https://doi.org/10.1016/j.infsof.2014.05.018S4054295

A Methodology for Eliciting and Ranking Control Points for Adaptive Systems

Designing an adaptive system to meet its quality constraints in the face of environmental uncertainties, such as variable demands, can be a challenging task. In cloud environment, a designer has to also consider and evaluate different control points, i.e., those variables that affect the quality of the software system. This thesis presents a method for eliciting, evaluating and ranking control points for web applications deployed in cloud environments. The proposed method consists of several phases that take a high-level stakeholders' adaptation goal and transform it into lower level MAPE-K loop control points. The MAPE-K loop is then activated at runtime using an adaptation algorithm. We conducted several experiments to evaluate the different phases of the methodology and we report the results and the lesson learnt

Aplicando una estrategia de mejora que incluye conceptos de requisitos funcionales y no funcionales

Organizations should set and reach business goals for varied purposes using the suitable strategies. Basically, a strategy specifies the activities, methods and another related resources that should be considered in order to achieve a given goal purpose. Goal purposes and their associated strategies can aim at evaluating, testing, developing, or maintaining some entity. Some concrete evaluation purposes such as to understand or monitor can be achieved by strategies embracing non-functional requirements definition, measurement, evaluation and analysis activities. Other specific evaluation purposes such as to improve or control also imply changing the target entity; therefore, strategies should embrace functional requirements definition activities as well. Moreover, specific development and maintenance purposes always involve functional requirements. In this work, we relate business and information need goals with functional and nonfunctional requirements concepts, which are paramount for well-defined strategies. Therefore, we specify vocabularies for them, and illustrate the applicability of an improving strategy –which embeds these concepts- in the context of a running example. Having well-structured vocabularies serving as common ground for diverse strategies may promote a more effective operationalization of projects dealing with evaluation, testing, development and maintenance goal purposes.Las organizaciones deben establecer y alcanzar metas de negocio para diferentes propósitos utilizando las estrategias adecuadas. Básicamente, una estrategia especifica las actividades, los métodos y los recursos relacionados que deben considerarse para lograr un determinado propósito. Los propósitos de las metas y sus estrategias asociadas pueden apuntar a la evaluación, prueba, desarrollo o mantenimiento de alguna entidad. Algunos propósitos específicos de evaluación, como comprender o monitorear, pueden lograrse mediante estrategias que abarcan actividades de definición de requisitos no funcionales, medición, evaluación y análisis. Otros propósitos de evaluación, como mejorar o controlar, implican además cambiar la entidad o su contexto; por lo tanto, las estrategias también deben incluir actividades de definición de requisitos funcionales. En cuanto a los propósitos específicos de desarrollo y mantenimiento, estos siempre implican requisitos funcionales. Este trabajo relaciona las metas de negocio y de necesidad de información con conceptos de requisitos funcionales y no funcionales, que son fundamentales para estrategias bien definidas. Por lo tanto, especificamos sus vocabularios e ilustramos la aplicabilidad de una estrategia de mejora –la cual embebe estos conceptos- mediante un ejemplo que desarrollamos a lo largo de las secciones. Tener vocabularios bien estructurados que sirvan de base común para diversas estrategias puede promover una operacionalización más efectiva de los proyectos que tienen que ver con propósitos de metas de evaluación, prueba, desarrollo y mantenimiento.Facultad de Informátic