Model of Virtualization
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.
Goals of Virtualization
Organizations are often seeking different things when using virtualization technology. An organization’s virtualization goals might include the following:
- Allowing any network-enabled device to access any network-accessible application over any network, even if that application was never designed to work with that type of device
- Isolation of one workload or application from another to enhance security or manageability of the environment
- Isolation of an application from the operating system, allowing an application to continue to function even though it was designed for a different version of the operating system
- Isolation of an application from the operating system, allowing an application to function on a foreign operating system
- Increasing the number of people that an application can support, by allowing multiple instances to run on different machines simultaneously
- Decreasing the time it takes for an application to run, by segmenting either the data or the application itself and spreading the work over many systems
- Optimizing the use of a single system, allowing it to work harder and more intelligently (that is, reducing the amount of time the processor sits idle)
- Increasing the reliability or availability of an application or workload through redundancy (if any single component fails, this virtualization technology either moves the application to a surviving system or restarts a function on a surviving system)
The organization’s choice of virtualization technology is dependent upon what it’s trying to accomplish. While there are typically many ways to accomplish these goals, some goals direct organizations’ decision-makers to select specific tools.