NDIS_QOS_CAPABILITIES structure (ntddndis.h)

Article
05/26/2021

The NDIS_QOS_CAPABILITIES structure specifies the NDIS Quality of Service (QoS) capabilities of a network adapter that supports the IEEE 802.1 Data Center Bridging (DCB) interface.

Syntax

typedef struct _NDIS_QOS_CAPABILITIES {
  NDIS_OBJECT_HEADER Header;
  ULONG              Flags;
  ULONG              MaxNumTrafficClasses;
  ULONG              MaxNumEtsCapableTrafficClasses;
  ULONG              MaxNumPfcEnabledTrafficClasses;
} NDIS_QOS_CAPABILITIES, *PNDIS_QOS_CAPABILITIES;

Members

Header

The type, revision, and size of the NDIS_QOS_CAPABILITIES structure. This member is formatted as an NDIS_OBJECT_HEADER structure.

The miniport driver must set the Type member of Header to NDIS_OBJECT_TYPE_QOS_CAPABILITIES. To specify the version of the NDIS_QOS_CAPABILITIES structure, the driver must set the Revision member of Header to the following value:

NDIS_QOS_CAPABILITIES_REVISION_1

Original version for NDIS 6.30 and later.

Set the Size member to NDIS_SIZEOF_QOS_CAPABILITIES_REVISION_1.

Flags

A ULONG value that contains a bitwise OR of flags that specify the NDIS QoS capabilities that a network adapter supports. The following flags are defined:

NDIS_QOS_CAPABILITIES_STRICT_TSA_SUPPORTED

If this flag is set, the network adapter supports the strict priority transmission selection algorithm (TSA). For more information about this algorithm, see Strict Priority Algorithm.

Note In order to be compliant with DCB, the network adapter must support the strict priority TSA.

NDIS_QOS_CAPABILITIES_MACSEC_BYPASS_SUPPORTED

If this flag is set, the network adapter supports the ability to bypass media access control security (MACsec) processing. For more information about MACsec, refer to the 802.1AE-2006 standard.

NDIS_QOS_CAPABILITIES_CEE_DCBX_SUPPORTED

If this flag is set, the network adapter and miniport driver supports the protocols that pre-date the IEEE 802.1Qaz Data Center Bridging Exchange (DCBX) protocol. These protocols include the Converged Enhanced Ethernet (CEE) suite of protocols.

NDIS_QOS_CAPABILITIES_IEEE_DCBX_SUPPORTED

If this flag is set, the network adapter and miniport driver supports the IEEE 802.1Qaz DCBX protocol. The DCBX protocol allows DCB parameters to be exchanged between two directly connected peers. This allows these peers to adapt and tune these parameters in order to optimize data transfer over the connection. For more information about this protocol, see Overview of Data Center Bridging.

Note If this flag is set, the miniport driver must reject any send requests for DCBX packets.

MaxNumTrafficClasses

A ULONG value that specifies the maximum number of NDIS QoS traffic classes that the network adapter supports. For more information, see NDIS QoS Traffic Classes.

Note In order for the network adapter to support NDIS QoS for DCB, it must support at least three traffic classes.

MaxNumEtsCapableTrafficClasses

A ULONG value that specifies the maximum number of QoS traffic classes that the network adapter can use with the Enhanced Transmission Selection (ETS) algorithm. This value must be less than or equal to the value of the MaxNumTrafficClasses member.

For more information about ETS, see Enhanced Transmission Selection (ETS) Algorithm.

Note In order for the network adapter to support NDIS QoS for DCB, it must support at least two ETS-capable traffic classes.

MaxNumPfcEnabledTrafficClasses

A ULONG value that specifies the maximum number of QoS traffic classes that the network adapter can use with the Priority-based Flow Control (PFC) algorithm. This value must be less than or equal to the value of the MaxNumTrafficClasses member.

For more information about PFC, see Priority-based Flow Control (PFC).

Note In order for the network adapter to support NDIS QoS for DCB, it must support at least one PFC-capable traffic class.

Remarks

The miniport driver registers the NDIS QoS capabilities of the underlying network adapter from the driver's MiniportInitializeEx function by following these steps:

The miniport driver initializes an NDIS_QOS_CAPABILITIES structure with the NDIS QoS capabilities of the network adapter.
The miniport driver initializes an NDIS_MINIPORT_ADAPTER_HARDWARE_ASSIST_ATTRIBUTES structure with the other hardware-assisted capabilities of the network adapter. The driver sets the HardwareQosCapabilities member of the NDIS_MINIPORT_ADAPTER_HARDWARE_ASSIST_ATTRIBUTES structure to a pointer to the NDIS_QOS_CAPABILITIES structure.
The miniport driver calls NdisMSetMiniportAttributes and sets the MiniportAttributes parameter to a pointer to the NDIS_MINIPORT_ADAPTER_HARDWARE_ASSIST_ATTRIBUTES structure.

The NDIS_QOS_CAPABILITIES structure is also returned in OID query requests of OID_QOS_CURRENT_CAPABILITIES and OID_QOS_HARDWARE_CAPABILITIES.

Requirements

Requirement	Value
Minimum supported client	Supported in NDIS 6.30 and later.
Header	ntddndis.h (include Ndis.h)