Virtualization, in computing, is the creation of a virtual (rather than actual) version of something, such as a hardware platform, operating system, a storage device or network resources.[1]
Virtualization can be viewed as part of an overall trend in enterprise IT that includes autonomic computing, a scenario in which the IT environment will be able to manage itself based on perceived activity, and utility computing, in which computer processing power is seen as a utility that clients can pay for only as needed. The usual goal of virtualization is to centralize administrative tasks while improving scalability and work loads.[1]
Main article: Hardware virtualization |
Hardware virtualization or platform virtualization refers to the creation of a virtual machines that acts like a real computer with an operating system. Software executed on these virtual machines are separated from the underlying hardware resources. For example, a computer that is running Microsoft Windows may host a virtual machine that looks like a computer with Mac OS X operating system. Subsequently, Mac OS X-based software can be run on that virtual machine.[1][2]
In hardware virtualization, the term host machine refers to the actual machine on which the virtualization takes place; the term guest machine, however, refers to the virtual machine. Likewise, the adjectives host and guest are used to help distinguish the software that run on the actual machine from those that run on the virtual machine. The software or firmware that creates a virtual machine on the host hardware is called Hypervisor or Virtual Machine Monitor.
Different types of hardware virtualization include:
Hardware-assisted virtualization is a way of improving the efficiency of hardware virtualization. It involves employing specially-designed CPUs and hardware components that help improve the performance of a guest environment.
Hardware virtualization must not be mistaken with hardware emulation: In hardware emulation, a piece of hardware imitates another, while in hardware virtualization, a hypervisor (a piece of software) imitates a computer hardware. Furthermore, a hypervisor must not be mistaken with an emulator. These two are defined similarly: Both are computer programs that imitate hardware. However, their domain of use in language differs.
See also: Mobile Virtualization |