Windows 7 has added new device driver interfaces (DDIs) to provide support for Mobile Broadband (MB) devices, beginning with Windows 7 Beta. MB miniport drivers are based on the NDIS 6.20 model. You can learn more about NDIS 6.20 here. The MB DDIs consist of 21 new OIDs, 20 new NDIS status notifications specific to MB, and their associated structures and enumerations. To learn more about writing an MB miniport driver for Windows 7, go here, also see this for the MB reference documentation.