Sky Computing: When Multiple Clouds Become One

Summary form only given. The growing number of announced commercial and scientific clouds strongly suggests that in the near future these providers will be differentiated according to the types of their services, their cost, availability and quality. Users will be able to use these and other criteria to determine which clouds best suit their needs, a plausible scenario being the case when users need to aggregate capabilities provided by different clouds. In such scenarios it will be essential to provide virtual networking technologies that enable providers to support cross-cloud communication and users to deploy cross-cloud applications. This talk will describe one such technology, its salient features and remaining challenges. It will also put forward the idea of virtual clouds, i.e. providers of computing services overlaid on more than one cloud. A virtual cloud spans across multiple cloud providers and presents the view of a single logical cloud. Virtual clouds would enable high-level computing services to be provided by third parties who do not own physical resources, could be short or long-lived and highly dynamic. Enabling technologies, challenges and examples of sky computing will be presented.