Virtualization is the provision of an abstraction between a user and a physical resource in a way that preserves for the user the illusion that he or she could actually be interacting directly with the physical resource. While you could imagine virtualizing any physical resource, the focus of this issue of Queue is the computing machine virtualization that is the current rage. The user gets a high-fidelity copy of what appears to be a complete computer system, while he or she is actually dealing with an abstraction layer known as the VMM (virtual machine monitor) that runs on the real machine and maps resources on behalf of the user.
Abstractions are useful, particularly if they are simple and efficient. The main benefit of any abstraction is the decoupling that it facilitates. With virtualization the user is able not to care about the hardware and how it actually behaves. As long as the performance characteristics are met, the user can also be freed from caring about who operates the hardware, where the hardware is located, and whose logo (if any) is on it. The ultimate extension of this is the utility computing model provided by virtualized compute services. It's worth looking at the benefits of virtualization from two points of view: from the perspective of the user who is above the VMM and from the perspective of the infrastructure provider beneath it.More information:
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