Initializing a Miniport-Intermediate Driver

A miniport-intermediate driver combines a miniport driver for a virtual device, a protocol driver, and a miniport driver for a physical device. A miniport-intermediate driver functions similarly to an intermediate driver layered over a miniport driver. Such a driver allows an intermediate driver to communicate directly with an underlying miniport driver without incurring the performance penalties that might result with two separate drivers.

To register its physical miniport driver, a miniport-intermediate driver calls the NdisMRegisterMiniportDriver function with appropriate parameters just as for any miniport driver. To register its virtual miniport, the driver calls NdisMRegisterMiniportDriver again, but with the NDIS_INTERMEDIATE_DRIVER flag set in the structure at MiniportDriverCharacteristics .

For each virtual or physical device instance of a miniport-intermediate driver, if the IMMiniport registry key is set to DWORD:0x0000001, NDIS calls the MiniportInitializeEx function that the driver registered for the virtual device. Otherwise, NDIS calls the driver's MiniportInitializeEx function that the driver registered for the physical device.