Introduction to 802.11 Miniport Drivers
802.11 miniport drivers are built on the same Network Driver Interface Specification (NDIS) model used for connectionless miniport drivers. In particular, 802.11 miniport drivers are very similar to 802.3 miniport drivers.
In addition, 802.11 miniport drivers provide support for the following:
- 802.3 emulation
Protocols are bound to the 802.11 miniport driver interface as if it were an 802.3 device. The 802.11 miniport driver must support all of the mandatory Ethernet objects as part of its 802.3 emulation. The 802.11 miniport driver can support any non-mandatory Ethernet objects.
In addition, packets sent to or received from the driver must be in 802.3 format. The driver translates the 802.3 media access control (MAC) header of outgoing packets to the appropriate 802.11 MAC header before passing the packets to the underlying network interface card (NIC). Similarly, the driver translates the 802.11 MAC header of incoming packets to the appropriate 802.3 MAC header before indicating the packets to the NDIS layer.
- 802.11 configuration by the operating system
Microsoft Windows XP and later operating systems query and set 802.11 parameters through the 802.11 WLAN objects. The miniport driver must support all of the mandatory 802.11 WLAN objects. It can support any non-mandatory 802.11 objects.
- 802.11 status indications to the operating system
The driver must support the media-specific status indications for 802.11 devices in addition to the media connection status indications for 802.3 devices.
The driver is only required to support the set of 802.11 status indications that are applicable to the capabilities of the 802.11 device. For example, if the device does not support WPA2 authentication, then the driver does not need to support the PMKID candidate list indication.
Although the 802.11 WLAN objects can be supported on all NDIS platforms, this design guide describes these objects with respect to NDIS version 5.1 and later. This design guide also describes the actions of these objects with respect to Windows XP and later operating systems.