Modelling and Analysing Highly-Configurable Services

Abstract

Since the emergence of XaaS and Cloud Computing paradigms, the number and complexity of available services have been increasing enormously. These services usually o er a plethora of con guration options, which can even include additional services provided as a bundled o er. In this scenario, usual tasks, such as description, discovery and selection, become increasingly complex due to the variability of the decision space. The notion of Highly-Con gurable Service (HCS) has been coined to identify such group of services that can be con gured and bundled together to perform demanding computing tasks. In this paper we characterize HCSs by means of an abstract model and a text-based, human-readable notation named SYNOPSIS that facilitates the execution of various service tasks. In particular, we validate the usefulness of our model when checking the validity of HCSs descriptions in SYNOPSIS, as well as selecting the optimal con guration with regards to user requirements and preferences by providing a prototype implementation.