PaaSport project has as goal to lift the barriers that cause the vendor lock-in problem and empower Cloud customers and Cloud application developers by allowing them to choose freely the Cloud PaaS offering that best fits their needs. This will also lead to encourage the entrance of European SME Cloud vendors in the PaaS market and to strengthen their market position relative to the big vendors. To achieve this goal PaaSport made an analysis of existing ontologies for cloud computing, in general, and PaaS, in particular, as well as the identification of the requirements the semantic models have to satisfy. In computer science terms, an ontology is a formal naming and definition of the types, properties, and interrelationships of the entities that exist in a particular domain of discourse. In addition, the report elaborates on the upper-level ontologies that have been reused and extended, so as to align the PaaSport semantic models with existing foundational schemata towards promoting reusability and knowledge sharing. In the scope of the PaaSport project, the use of semantic models is twofold:
- Aligning the models of different PaaS offerings, thus resolving semantic interoperability conflicts among heterogeneous Cloud PaaS offerings that exploit diverse platform and application models, offered service descriptions, offered resources, Quality of Service, SLA formats, billing policies and other important issues (such as location of service or service certifications); and,
- Bridging the gap between business application requirements and PaaS offerings capabilities, thus, facilitating the matchmaking and the identification of the specific PaaS that fulfills the business and technical requirements of a particular application.