WiFiCx QoS R1

  • Article

QoS R1 introduces advanced traffic management capabilities for WiFiCx devices. QoS R1 enables prioritization of Wi-Fi data packets through Mirrored Stream Classification Service (MSCS) and QoS Mapping (DSCP-to-UP Mapping). These features enhance network efficiency and user experience by applying appropriate QoS policies to different types of traffic.

QoS R1 functionality encompasses sections 3.1 and 3.2 in the WFA Wi-Fi QoS Management Specification.

Starting with WiFiCx version 1.2, you can incorporate QoS R1 features into your WiFiCx client driver. QoS R1 is only available in the WiFiCx driver model. This article outlines the driver changes required to support these features.

QOS R1 driver requirements

To support the QoS R1 feature suite, a WiFiCx client driver must:

  1. Support WiFiCx version 1.2 or higher.
  2. Support WMM (Wi-Fi Multimedia) standards.
  3. Have the capability to send/receive action frames.
  4. Introduce support for OS-configurable Wake on Incoming Action Frame.
  5. Communicate OS support of QoS features to Access Points (AP) through (re)association frames.
  6. Indicate driver support for both MSCS and QoS Mapping if the preceding criteria are met.

MSCS

To support MSCS:

  1. The driver sets the MSCSSupported field in WIFI_STATION_CAPABILITIES to TRUE.

  2. If the driver sets MSCSSupported to true, Windows will indicate MSCS support by marking the MSCSSupported bit in WDI_TLV_CONNECTION_SETTINGS.

  3. If Windows sets the MSCSSupported bit to 1, the driver must set the Mirrored SCS field of the Extended Capabilities element (Bit 85) to 1 in the (re)association request.

Following a successful association, Windows will attempt to set up an MSCS session with the AP:

  1. Windows sends an OID_WDI_TASK_SEND_REQUEST_ACTION_FRAME task to the driver.

  2. This task prompts the driver to send an MSCS Request Action Frame to the AP with default TCLAS mask parameters (as specified in the WFA test specification).

  3. The driver indicates the status of the Action Frame response via NDIS_STATUS_WDI_INDICATION_ACTION_FRAME_RECEIVED.

When MSCS support is indicated, the driver must support Wake on Incoming Action Frame for MSCS. When going to Dx with an active MSCS session, the OS will configure the driver to wake on receipt of an MSCS response frame.

The OS may prompt the driver to send an MSCS Request Action Frame to the AP to request MSCS teardown via the OID_WDI_TASK_SEND_REQUEST_ACTION_FRAME task.

QoS Mapping

To support QoS Mapping:

  1. The driver sets the DSCPToUPMappingSupported field in WIFI_STATION_CAPABILITIES to TRUE.

  2. If the driver sets DSCPToUPMappingSupported to true, Windows will indicate support for QoS Mapping by marking the DSCPToUPMappingSupported bit in WDI_TLV_CONNECTION_SETTINGS.

  3. If Windows sets the DSCPToUPMappingSupported bit to 1, the driver must set the QoS Map field of the Extended Capabilities element (Bit 32) to 1 in the (re)association request.

After QoS Mapping is established through either (re)association or a QoS Map Configure Action Frame that includes a QoS Map element, the OS will set appropriate UP values based on mapping received from the AP.

For successful associations in which QoS Mapping support is indicated, the driver must:

  1. Include the WDI_TLV_ASSOCIATION_RESPONSE_FRAME in the WDI_TLV_ASSOCIATION_RESULT.

  2. Indicate incoming QoS Map Configure Action Frames to the OS via NDIS_STATUS_WDI_INDICATION_ACTION_FRAME_RECEIVED.

When QoS Mapping support is indicated, the driver must support Wake on Incoming Action Frame for DSCP-to-UP Mapping. When going to Dx with QoS Mapping established, the OS will configure the driver to wake on receipt of a QoS Map Configure Action Frame.