Virtualizacion

Monolithic Hypervisor
Monolithic hypervisor design involves using hypervisor-aware device drivers that are hosted within
and managed by the hypervisor as shown in Figure 2-3 .
HypervisorMonolithic
Hardware
VM1
Admin
VM2 VM3
Drivers
FIGURE 2-3 Monolithic hypervisor platforms require hypervisor-aware device drivers .

The monolithic design choice results in some benefitsbut also some drawbacks . For example,
monolithic hypervisors do not need a controlling, or parent, operating system because all guest
operating systems interact directly with the underlyingphysical hardware of the host computer by
using hypervisor-aware device drivers . This is an example of the benefit of the monolithic design
.

On the other hand, the fact that device drivers mustbe specifically developed for the hypervisor
creates significant challenges because there are so many different types of motherboards, storage
controllers, network adapters, and other types ofhardware devices on the market . The result is
that vendors of monolithic hypervisor platforms have to work closely with manufacturers of hardware
devices to ensure these manufacturers develophypervisor-aware versions of device drivers for their
hardware . It also means that vendors
of monolithic hypervisor platforms are dependent on manufacturers of hardware devices to supply
such driversfor their products . The result is that the number of devices that can be used in
virtualized operating system environments running on monolithic hypervisor plat- forms can be more
limited thanwhen those same operating system environments are run directly on physical computers .

One important point is that in this design you’re ignoring one of the most important security
tenets:defense in depth . With defense in depth, you provide multiple layers of defense to
prevent against attacks . In this model, there is no defense in depth because everything is
running in the most...