Quoting from Network World:
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The PCI-SIG Working Group is developing a specification that adds I/O virtualization capability to PCIe. This functionality lets network administrators virtualize or share peripherals and endpoints across different CPUs or CPU complexes.
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In the new specification, root complex topologies provide two levels of I/O virtualization. In the first level, called single-root I/O virtualization (IOV), the virtualization capability is provided by the physical endpoint itself. The endpoint supports one or more virtual endpoints, and mechanisms are used to enable each virtual endpoint to directly sink I/O and memory operations from various system images, and source direct memory access, completion and interrupt operations to a system image without run-time intervention.n the second level, called multiroot IOV, the virtualization capability is extended by the use of a multiroot switch and a multiroot endpoint. These switches and endpoints have mechanisms to let multiple root complexes and system images share common endpoints…
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