A Distributed Virtual Infrastructure (VI) Manager is responsible for the efficient management of the virtual infrastructure as a whole, by providing functionality for deployment, control and monitoring of groups of interconnected Virtual Machines (VMs) across a pool of resources. An added functionality of these management tools is the dynamic scaling of the virtual infrastructure with resources from remote providers, so seamless integrating remote Cloud resources with in-house infrastructures. This novel functionality allows to add and remove capacity in order to meet peak or fluctuating service demands, so providing the foundation for interoperation between Cloud infrastructures. The distributed virtual infrastructure would run on top of a geographically distributed physical infrastructure consisting of resources from the private cloud and several external cloud providers.

Following the terminology defined by the Grid community for getting Grids to work together, we use the term interoperation for the set of techniques to get production Cloud infrastructures to work together using adapters and gateways. While interoperability would refer to the ability of Cloud infrastructures to interact directly via common open standards.

Since release 1.0, OpenNebula distribution includes the plugins required to supplement local resources with Amazon EC2 resources to satisfy peak or fluctuating demands. This novel feature has been illustrated in several use cases for computing clusters and web servers. The open and flexible architecture of OpenNebula enables to create new plugins to access other cloud providers. In order to illustrate this and to provide KVM users with an utility access to remote resources, the OpenNebula team has just released the plugins required to dynamically grow the infrastructure using ElasticHosts resources. ElasticHosts is the world’s first public cloud based upon KVM, providing scalable and flexible virtual server capacity for cloud hosting. An interesting result is that a private infrastructure could dynamically grow using resources from different Cloud providers according to provisioning policies based on resource availability, performance, costs, availability...

The release of these new plugins represents a new step towards an open-source framework for cloud infrastructure federation, which is one of the main goasl of the Reservoir project, European research initiative in virtualized infrastructures and cloud computing.