The NOVA OS Virtualization Architecture is a research project aimed at constructing a secure virtualization environment with a small trusted computing base. NOVA consists of a microhypervisor and an unprivileged multi-server user environment running on top of it.
Like third-generation microkernels, the NOVA microhypervisor uses a capability-based authorization model and provides only basic mechanisms for virtualization, spatial and temporal separation, scheduling, communication and delegation of platform resources. The disaggregated user environment implements additional functionality, such as device drivers, system services and policies. On machines with hardware virtualization features, NOVA can run multiple unmodified guest operating systems concurrently. Each VM has its own associated virtual-machine monitor (VMM) that runs as an unprivileged user application on top of the microhypervisor.