US Patent 8719914 Virtual computing infrastructure

A system has a virtual overlay infrastructure mapped onto physical resources for processing, storage and network communications, the virtual infrastructure having virtual entities for processing, storage and network communications. Virtual infrastructures of different users share physical resources but are isolated and have their own management entities. An interface between infrastructures allows controlled relaxation of the isolation, using a gateway between virtual nets, or shared virtual storage devices. This can allow businesses to share data or applications, while maintaining control of security.