IntelŴVirtualization Technology for Directed I/O

Intel ® Virtualization Technology Δ for Directed I/O (VT-d) is the next important step toward comprehensive hardware support for the virtualization of Intel ® platforms. VT-d extends Intel's Virtualization Technology (VT) roadmap from existing support for IA-32 (VT-x) (1) and Itanium ® processor (VT-i) (2) virtualization to include new support for I/O-device virtualization. This paper surveys a variety of established and emerging techniques for I/O virtualization and outlines their associated problems and challenges. We then detail the architecture of VT-d and describe how it enables the industry to meet the future challenges of I/O virtualization.