When queried, the OID_802_11_SUPPORTED_RATES OID requests that the miniport driver return the underlying NIC's data rate set, which includes the data rates that the NIC's radio supports.
Data rate sets are encoded as eight bytes. Each byte describes a single rate in units of 0.5 Mbps. Rates from the IEEE 802.11 BSSBasicRateSet that are included in the supported rates are used, for example, for control and broadcast frames.
Each supported rate from the BSSBasicRateSet is encoded as a byte with the most significant bit (bit 7) set to 1. For example, a 1-Mbps rate in the BSSBasicRateSet is encoded as 0x82.
Rates that are not included in the BSSBasicRateSet are encoded with the most significant bit set to zero. For example, a 2-Mbps rate that does not belong to the BSSBasicRateSet is encoded as 0x04.
The data type for this OID is the NDIS_802_11_RATES array, which is defined as follows:
If the device supports less than eight rates, the driver must set the unused entries at the end of the array to zero.
If the device supports more than eight rates, the miniport driver returns the highest eight rates.