3. Types of Virtualization

3.1. Full Virtualization

Red Hat Enterprise Linux contains virtualization packages and tools to run fully virtualized, unmodified, operating system guests. This provides companies with the ability to consolidate older systems onto newer, more efficient hardware, and reduces physical space and operating costs involved with powering and cooling older, less efficient systems. Full virtualization offers lower I/O performance than native (or bare-metal) installations of operating systems.

3.2. Para-Virtualization

Para-virtualization is a virtualization technique which involves running modified versions of operating systems. The para-virtualized operating system is modified to be aware that it is being virtualized, offering an increased ability for optimization as the guest is more aware of its environment. Performance is generally very close to running bare-metal, non-virtualized operating systems.

3.3. Para-virtualized drivers

Para-virtualization and full virtualization can be combined to allow unmodified operating systems to receive near native I/O performance by using para-virtualized drivers on fully virtualized operating systems.
The para-virtualized drivers contain storage and network device drivers for fully virtualized Microsoft Windows® guests. The drivers provide Microsoft Windows® guests running on Red Hat Enterprise Linux with enhanced disk and network I/O performance.