The virtualization of I/O resources is an important step toward enabling a significant set of emerging usage models in the data center, the enterprise, and the home. VT-d support on Intel platforms provides the capability to ensure improved isolation of I/O resources for greater reliability, security, and availability.

Specifically, VT-d supports the remapping of I/O DMA transfers and device-generated interrupts. The architecture of VT-d provides the flexibility to support multiple usage models that may run un-modified, special-purpose, or "virtualization aware" guest OSs. The VT-d hardware capabilities for I/O virtualization complement the existing Intel® VT capability to virtualize processor and memory resources. Together, this roadmap of VT technologies offers a complete solution to provide full hardware support for the virtualization of Intel platforms.

Ongoing and future developments within the virtualization hardware and software communities will build upon VT-d to ensure that the requirements for sharing, security, performance, and scalability are being met. I/O devices will become more aware of the existence of VT-d to ensure efficient caching and consistency mechanisms to enhance their performance. Given the protection provided by VT-d, future I/O devices will emerge that are sharable among multiple guest OSs. With VT-d, software developers can develop and evolve their architectures that provide fully protected sharing of I/O resources that are highly available, provide high performance, and scale to increasing I/O demands.