Infrastructure virtualization centers on using software and preexisting hardware to emulate other software or hardware. Virtualization came into being with modern computers, but really took off at the beginning of the 21st century with full server virtualization options. It is possible to virtualize nearly any piece of hardware or software, making the scope of this technology very broad. Some of the more common applications of infrastructure virtualization are operating system emulation, virtual desktops, and virtual servers.
The technology that eventually became infrastructure virtualization began in the mid-1960s. At its onset virtualization had two main goals, the creation of a "virtual memory" system and a "machine emulator" that was able to run software designed for other computer platforms. While several companies achieved these goals, the results were mixed and virtualization research continued.
The middle years of research had their ups and downs. True virtual machines came into development in the mid-1970s. These were programs that mimicked entire computers so closely that it was possible to run software through them. These early virtual machines rarely had enough power to run applications of any real size or complexity, but the technology had enough potential that several companies pursued research. The infrastructure virtualization research during the 1980s and 1990s brought several improvements but few breakthroughs.
In 2003, the first open-source hypervisor was released. This program allowed the monitoring of multiple operating systems running concurrently on a single machine. While virtual machine monitors had existed since the mid-1980s, this program was free, comprehensive, and powerful. With this software and multi-cored processors, it was possible to run multiple virtual servers on nearly any real server with little reduction in overall power. By running virtual servers, a company could cut power costs and increase the overall power of their network.
In the corporate world, virtualization is often the norm. Server rooms may have machines running half a dozen or more virtual servers with little to no reduction in speed or power. Virtual desktops have replaced the need for a computer for each worker. Instead of having his own machine, a single version of a base machine copies itself to the network and gives the worker access to a virtual computer. All of his information is saved on a central server.
Home computer users bump into infrastructure virtualization all the time, although many don't realize it. Programs that run through web portals without any form of installation are usually virtualized, often to reduce transmission lag and improve performance. Applications that were originally designed to run on one operating system (OS) can now run on multiple systems due to virtual OS wrappers. These programs run inside a host program and convert the input and output to that of the proper operating system. This is especially common when moving PC-based games to other systems.
