19.4 Summary

Virtualization is defined as the ability to run multiple guest operating systems within a single host operating system. A number of approaches to virtualization have been developed including guest operating system and hypervisor virtualization. Hypervisor virtualization falls into two categories known as Type-1 and Type-2. Type-2 virtualization solutions are categorized as para-virtualization, full virtualization and hardware virtualization, the latter making use of special virtualization features of some Intel and AMD processor models.

Virtual machine guest operating systems have a number of options in terms of networking including NAT, direct connection (MacVTap) and network bridge configurations.