Dan Kusnetzky - Virtualization: A Managers Guide

Analysts often find that it is much easier to understand a complex environment if they build a reference model. The Kusnetzky Group Model of virtualization () is an example. Reference models must be comprehensive and the segments must be mutually exclusive to be really useful.

Over time, most of the functions that computers perform have in some way benefited from virtualization. It is important to note that some products incorporate features that straddle one or more layers of the model. Those products are typically assigned to the layer describing their most commonly used functions. As one would expect, industry and technological changes require that the model be revisited regularly to determine if previous categories should be merged into a single new category or deleted.

Figure 1-1. Kusnetzky Group model of virtualization

Virtualization is a way to abstract applications and their underlying components away from the hardware supporting them and present a logical or virtual view of these resources. This logical view may be strikingly different from the physical view. The goal of virtualization is usually one of the following: higher levels of performance, scalability, reliability/availability, agility, or to create a unified security and management domain.

This virtual view is constructed using excess processing power, memory, storage, or network bandwidth.

Virtualization can create the artificial view that many computers are a single computing resource or that a single machine is really many individual computers. It can make a single large storage resource appear to be many smaller ones or make many smaller storage devices appear to be a single device.