A Survey on Dynamic SLAs for Fog Computing

ABSTRACT The concept of a service‐level agreement (SLA), a contractual arrangement between providers and customers, is firmly established in the software engineering field. However, introducing enhanced dynamism to this service contract, in one or more directions to be subsequently specified, constitutes a challenge, an important step for the Computer Engineering community, and, in our case, an anticipated contribution to the fogSLAAntillas (fogSLA) collaborative project. Consequently, this paper seeks to improve the understanding, classification, and articulation of the terminology associated with dynamic SLAs as it has evolved in the literature. The discussion extends to methodological and practical options for integrating this concept within the fogSLA project framework. On this occasion, we share our experience with dynamic SLA in the context of scheduling pods for a Kubernetes cluster. Thus, the mentioned practical work is specifically devoted to the concept of dynamicity in SLA within the Cloud‐Fog‐Edge continuum. This survey commences with a literature review and subsequently explores potential research directions applicable to the fogSLA project and to the broader Cloud, Fog, and Edge Computing communities. Some of these paths are already well defined, but would require community endorsement to attain the status of standards in the future. Therefore, we propose novel ideas and extend beyond a mere survey of the existing literature. The main contributions of this paper are, first, to align with the goal of qualitative research by deepening the understanding of the dynamic SLA topic and the potential challenges it entails, and second, to demonstrate how we have practically tackled the problem of dynamic SLAs within a project involving industrial partners, thereby indicating a real demand for this concept.