The ndis device class consists of devices that can be associated with network driver interface specification (NDIS) media access control (MAC) drivers to support network communications. You access these devices by using functions.
The lineGetID and phoneGetID functions fill a VARSTRING structure, setting the dwStringFormat member to the STRINGFORMAT_BINARY value and appending these additional members:
HANDLE hDevice; // NDIS connection identifier
CHAR szDeviceType[1]; // name of device
The hDevice member is the identifier to pass to a MAC, such as the asynchronous MAC for dial-up networking, to associate a network connection with the call/modem connection. The szDeviceType member is a null-terminated ASCII string specifying the name of the device associated with the identifier.