Category:Virtualization: Difference between revisions

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In computing, virtualization is a broad term that refers to the abstraction of computer resources:

   * Virtual machine (VM), a software implementation of a machine (computer) that executes programs like a real machine
         o Platform virtualization, which separates an operating system from the underlying platform resources
               + Full virtualization, sensitive instructions replaced by binary translation or trapped by hardware - all software can run in the VM, e.g. IBM's CP/CMS, VirtualBox, VMware Workstation
               + Hardware-assisted virtualization, CPU traps sensitive instructions - runs unmodified guest OS; used e.g. by VMware Workstation, Xen, KVM
               + Partial virtualization, for specific applications rather than the operating system
               + Paravirtualization, a virtualization technique that presents a software interface to virtual machines that is similar, but not identical, to that of the underlying hardware, thereby requiring guest operating systems to be adapted
               + Operating system-level virtualization, a method where the operating system allows for multiple user-space instances (virtual hosting, chroot jail + resource management)
         o Application virtualization, the hosting of individual applications on alien hardware/software
               + Portable application, a computer software program that runs from a removable storage device as a USB flash drive
               + Cross-platform virtualization, allows software compiled for a specific CPU and operating system to run unmodified on different CPUs and/or operating systems
               + Virtual appliance, a virtual machine image designed to run on a virtualization platform
               + Emulation or simulation
   * Virtual memory, which allows uniform, contiguous addressing of physically separate and non-contiguous memory and disk areas
   * Storage virtualization, the process of completely abstracting logical storage from physical storage
   * Network virtualization, creation of a virtualised network addressing space within or across network subnets
   * Virtual private network (VPN), a computer network in which some of the links between nodes are carried by open connections or virtual circuits in some larger network(s), such as the Internet
   * Memory virtualization, aggregates RAM resources from networked systems into virtualized memory pool
   * Desktop virtualization, the remote manipulation of a computer desktop
   * Timeline of virtualization development, further work in this area