ABSTRACT
VMware ESX is an enterprise class x86 architecture virtualization platform. While there is a clear buzz around the term virtualization right now, the term and the technology is still new to many people. Virtualization isn’t new. It has actually been around for more than 40 years. Virtualization is the act of hiding, or masking, resources to appear different than they actually are. This shouldn’t be confused with multitasking or hyperthreading technologies. Multitasking allows one or more CPU(s) to manage a single operating system and one or more applications. Hyperthreading behaves like multitasking, with the exception that one or more CPU(s) behaves as if each individual CPU is multiple logical CPUs. Also shown in Figure 3.1, virtualization allows one or more physical CPU(s) to be represented as a number of virtual CPUs while at the same time creating an isolated set of hardware. In turn, a single physical system can appear to be one or more different virtual systems, each with their own set of virtual hardware.
