%0 Generic %A Petcu, Dana %A Crǎciun, Ciprian %A Neagul, Marian %A Lazcanotegui, Iñigo %A Rak, Massimiliano %T Building an interoperability API for Sky computing %J Proceedings of the 2011 International Conference on High Performance Computing and Simulation, HPCS 2011 %D 2011 %U https://hdl.handle.net/11556/1571 %X The federation of Cloud resources can be treated at different levels of abstractions. In this paper we focus on application programming interfaces for building Cloud-based applications using services from multiple Cloud providers. A full stack of APIs is proposed to decouple the development of a Cloud-based application from its deployment and execution. A particular attention is paid to the design of the interoperability API aiming to provide programming language interoperability and protocol syntax or semantic enforcements. %~