Decomposition of Reliability Requirements for Self-Adaptive Systems Using the NFR Framework
Resumo
Context: Self-adaptive systems (SAS) can change their behavior at runtime according to their needs and problems, presenting dynamic and complex operations. Problem: One way to help ensure the quality of SAS is to correctly address non-functional requirements (NFRs), such as security, usability, and reliability. However, dealing with NFRs is naturally a difficult task, as they have some problems related to their relationships with other NFRs or their sub-characteristics. Solution: SASs have characteristics directly linked to NFRs or quality characteristics that must be adequately maintained for the system to work. One way to map the conflicts of RNFs is using SIGs (Softgoal Interdependency Graph), basic units that represent non-functional requirements or generic and flexible goals. Aiming to support the implementation of NFRs in SAS and contribute to improving the quality assurance of these systems, this work aims to propose a reliability SIG for self-adaptive systems. IS Theory: General systems theory, specifically the interfaces between different parts of systems and solutions that communicate, exchanging information. These parts can be systems from different institutions that require integration, consisting of Information Systems. Method: We conducted a systematic mapping of the literature to identify which NFRs are most used in evaluating SASs. Next, the reliability NFRs decomposition step was performed, generating a reliability SIG for SAS as a product, which was evaluated by specialists in SAS. Summary of Results: As the main results, we obtain that: (i) reliability was the most cited characteristic among the 31 selected studies, (ii) availability was the most cited in the works, and (iii) reliability significantly influences the properties and performance of SAS, in addition to impact service quality. The SIG developed throughout this study can be used as a support base for developers or requirements analysts interested in understanding the relationships between the reliability NFR in SASs. Contributions and Impact in the IS area: The results contribute to SI in bringing discussions about quality of SAS is to correctly address non-functional requirements (NFRs). The main contribution is a systematic mapping and SIG.
