Towards Multi-Clouds engineering

Multi-Clouds are nowadays motivated by the needs of Cloud service consumers to ensure a certain level of service quality. Main requirements and challenges of the developing Multi-Clouds are analyzed in this paper. A particular attention is payed on the application and service portability. As complementary solution to the current approaches of using uniform application programming interfaces or standard protocols, a model-driven engineering approach dealing with the quality of service in Multi-Clouds is discussed.