[ Thanks to Inkslinger for this link.
]
“The netkvm driver is a Network Driver Interface
Specification (NDIS) miniport network driver for Windows guests and
viostor is a Storport miniport driver, also for Windows guests.“Windows Server 2003 and later operating systems support
Storport, a storage port driver that is suitable for use with
high-performance buses, such as fibre channel buses and RAID
adapters, according to Microsoft.”