Full virtualization is an implementation variant of server virtualization. Virtualization is achieved by replicating a complete hardware environment for the virtual machine( VM). The Virtual Machine Monitor( VMM) runs as an application on an operating system and provides virtual environments for guest operating systems at runtime, from which the real hardware is completely hidden, but which at the same time find a true-to-original - virtual - hardware environment right up to a simulated BIOS.
Thus the normal operating system-sided device drivers can be used, whereby from the VMM usually only a small number of different devices, e.g. network cards, are made available. Examples of products based on this principle are VMwareWorkstation + Server, Microsoft Virtual PC + Server.
Their architecture is quite straightforward, as a guest operating system finds a familiar environment and does not require any modifications. However, it has a negative effect on the runtime speed, because due to the unfavorable architecture of x86 processors for virtualization, the VMM has to execute time-consuming context switches to simulate a real environment for each guest and at the same time prevent illegal CPU instructions.