QuoteKVM's approach differs from that of Xen, which governs access to hardware using a combination of a lightweight "hypervisor" foundation and a privileged operating system, which is typically Linux. KVM's method is conceptually closer to one of two approaches used by VMware--the "hosted" model used in the free VMware Server and Player products. In that model, guest virtual machines run atop a copy of the operating system. In the second VMware approach, used in the higher-end ESX Server product, a full-featured, heavyweight hypervisor governs access to underlying hardware.
QuoteSupported Operating Systems: Windows Server 2003, Standard Edition (32-bit x86); Windows Server 2003, Standard x64 Edition; Windows Vista Business; Windows Vista Business 64-bit edition; Windows Vista Enterprise; Windows Vista Enterprise 64-bit edition; Windows Vista Ultimate; Windows Vista Ultimate 64-bit edition; Windows XP Professional Edition ; Windows XP Professional x64 Edition ; Windows XP Tablet PC Edition
An x64-based or an x86-based computer with a 400 MHz or faster (1 GHz recommended) processor with L2 cache
QuoteXen 3.0.4 changes this. By including what's called a virtual frame buffer, Xen's controlling "host" operating system can capture video data written to a specific part of memory and then send it to the display. The technology lets users see virtual machines through a graphical interface, a feat competitors such as EMC's VMware can already accomplish, rather than the text-based command line suitable chiefly for the technically proficient.
QuoteAccording to Microsoft's Windows Vista End User License Agreement (EULA), the platform's Home Basic and Home Premium editions cannot be run as a virtual machine (VM). Such restrictions do not apply to the business versions of the OS. "Today, customers using this technology are primarily business customers addressing application compatibility needs or technology enthusiasts," the spokesperson said. "For everyday use, Windows Vista Home and Home Premium cannot be installed in any virtual machine technology, but Business and Ultimate versions can. Each virtual installation of Windows requires a new license just as it was for Windows XP."