An Ontology for the Cloud in mOSAIC

Cloud Computing has emerged as a model to provide access to large amount of data and computational resources by using simple interfaces. Computing is being transformed to a model consisting of services and they are delivered without regard to where and how services are hosted. The easiness of using and conguring resources has made this model widespread and several enterprises now oer Cloud-based services to end users and businesses. Anyway, Cloud Computing is still an emerging architecture, and new providers with dierent services rise every month. In addition, it is very hard to nd a single provider which oers all services needed by end users. For this reason, a way to provide a common access to Cloud services and to discover and use required services in Cloud federations is appealing. This is a problem, since dierent Cloud systems and vendors have dierent ways to describe and invoke their services, to specify requirements and to communicate. mOSAIC project addresses these problems by dening a common ontology and it aims to develop an open-source platform that enables applications to negotiate Cloud services as requested by users. The main problem in dening the mOSAIC ontology is in the heterogeneity of terms used by Clouds vendors, and in the number of standards which refer to Cloud Systems with dierent terminology. In this work the mOSAIC Cloud Ontology is described. It has been built by analysing Cloud standards and proposals. The Ontology has been then rened by introducing individuals from real cloud systems.