19.2 Hypervisor Virtualization
In hypervisor virtualization, the task of a hypervisor is to handle resource and memory allocation for the virtual machines in addition to providing interfaces for higher level administration and monitoring tools. Hypervisor based solutions are categorized as being either Type-1 or Type-2.
Type-2 hypervisors (sometimes referred to as hosted hypervisors) are installed as software applications that run on top of the host operating system, providing virtualization capabilities by coordinating access to resources such as the CPU, memory and network for guest virtual machines. Figure 19-2 illustrates the typical architecture of a system using Type-2 hypervisor virtualization:
Figure 19-2
To understand how Type-1 hypervisors work, it helps to understand a little about Intel x86 processor architecture. The x86 family of CPUs provides a range of protection levels known as rings in which code can execute. Ring 0 has the highest level privilege...
