Quality in Use and Software Greenability Coral Calero, Mª Ángeles Moraga Instituto de Tecnologías y Sistemas de la Información University of Castilla-La Mancha Ciudad Real, Spain {Coral.Calero; MariaAngeles.Moraga}@uclm.es Manuel F. Bertoa Departamento de Lenguajes y Ciencias de la Computación University of Malaga Malaga, Spain bertoa@lcc.uma.es Leticia Duboc Universidade do Estado do Rio de Janeiro Rio de Janeiro, Brasil. leticia@ime.uerj.br Abstract— Software sustainability has recently begun to gain importance. However, although proposals concerning what it is and how to achieve it are starting to appear, until now, there have been very few proposals on how to model it. Sustainable development consists of three dimensions: Social sustainability, Economic sustainability and Environmental sustainability; the latter being more closely related to technical aspects. There are also three environmental impact levels for ICTs: direct environmental effects of production and use of ICTs, indirect environmental impacts related to the effects of ICTs and indirect effects on the environment. In this paper, we focus on environmental sustainability and the first environmental impact level, and more concretely, on the direct environmental effect of software use. We specifically propose a greenability in use characteristic to be considered as part of the quality in use model proposed by the ISO 25010 standard. This model can be used using measures, indicators, or even Bayesian Networks in order to link it with product quality. We therefore present an example of a Bayesian Network that links product quality to greenability in use. Our eventual goal is to provide developers with indicators and guidelines on how to develop an environmentally friendly software product. Index Terms—Software quality, green software, greenability I. INTRODUCTION Quality is currently among organizations’ main goals because nowadays the industry made efforts to obtain the ISO9000 or CMMI (even been mandatory in the USA if a company want to collaborate with the government). The SWEBOK (Software Engineering Body of Knowledge) [16], the main reference guide of software engineers includes a specific chapter about software quality and how to apply it to the software engineering discipline. A large number of organizations provide similar products, thus permitting consumers to choose from a wide variety of brands. The survival of these organizations depends, to an increasing extent, on the quality of the products and services provided. The need for quality is also present in the software industry, which has consequently become concerned about software quality. This has led to the appearance of the ISO/IEC 25000 series of standards, representing the evolution of the ISO/IEC 9126 and the ISO/IEC 14598 series. This family is divided into five divisions, one of which, the ISO/IEC 2501n (and more concretely the 25010), presents various software quality models. However, none of these models considers sustainability or the ecological aspects of software products. This is, from our point of view, an important weakness of the standards, since sustainability is gaining more and more importance in society in general and in industry in particular. We believe this characteristic should also be considered in the software quality context. Our proposal is to complete the quality models of the standard in such a manner that we will be able to take sustainability into consideration when developing or evaluating a software product. This will allow to create the necessary foundation to incorporate into and assess greenability of a software product. In this paper, we present our progress with respect to this goal. The reminder of this paper is organized as follows: Section two presents important aspects of sustainability in general. Section three discusses the importance of sustainability in the software context and presents the focus of our research. Section four describes the relevant aspects of the ISO/IEC 25010 standard and its quality models. The product greenability characteristic, proposed by the authors in a previous work, is also shown in the fourth section. In Section five, we propose the greenability in use, a new characteristic to be added to the quality in use model of the standard. Some examples of the levels of impact of this new characteristic are shown in Section six. Section seven shows how to combine the product quality and the quality in use models by means of Bayesian networks. Finally, Section eight presents our conclusions and future work. II. SUSTAINABILITY One of humanity’s current challenges is to conserve the environment and attain a sustainable economic and social development. Sustainable development is commonly defined as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [9]. According to the United Nations World Commission on Environment and Development [17], sustainable development needs to satisfy the requirements of the three dimensions of society, economy, and the environment. Sustainability has recently become more and more important to businesses. A business that fails to have a sustainable development as one of its top priorities could