21.2.1 QoE Measurement Collection Activation and Reporting

The feature is activated in the gNB either by direct configuration from the OAM system (management-based activation), or by signalling from the OAM via the 5GC (signalling-based activation), containing UE-associated QoE configuration. One or more QoE measurement collection configurations can be activated at a UE per service type, and each QoE measurement configuration is uniquely identified by a QoE reference.

For signalling-based QoE measurements, the OAM initiates the QMC activation for a specific UE via the 5GC, and the gNB receives one or more QoE measurement configurations by means of UE-associated signalling. The QoE measurement configuration for signalling-based QMC activation includes an application layer measurement configuration list and the corresponding information for QoE measurement collection, e.g., QoE reference, service type, MCE IP address, slice scope, area scope, MDT alignment information, the indication of available RAN visible QoE metrics and assistance information.

For management-based QMC activation, the OAM sends one or more QoE measurement configurations directly to the gNB. The QoE measurement configuration for management-based QMC activation also includes an application layer measurement configuration list and the corresponding information for QoE measurement collection. The gNB selects UE(s) that have the required QoE measurement capability, and that meet the measurement collection criteria related to area scope and slice scope.

An application layer measurement configuration received by the gNB from the OAM or from the 5GC is encapsulated in a transparent container, which is forwarded to a UE as measConfigAppLayerContainer in the RRCReconfiguration message (there can be multiple configurations in the same message). Application layer measurement reports received from UE's application layer are encapsulated in a transparent container and sent to the network in the MeasurementReportAppLayer message, as specified in TS 38.331 [12]. The UE can send multiple application layer measurement reports to the gNB in one MeasurementReportAppLayer message. In order to allow the transmission of application layer measurement reports which exceed the maximum PDCP SDU size, segmentation of the MeasurementReportAppLayer message may be enabled by the gNB. A measurement configuration application layer ID conveyed in the RRC signalling is used to identify the application layer measurement configuration and report between the gNB and the UE. The measurement configuration application layer ID is mapped to the QoE reference in the gNB, and the gNB forwards the application layer measurement report to MCE together with the QoE reference. The gNB can release one or multiple application layer measurement configurations from the UE in one RRCReconfiguration message at any time. The UE may additionally be configured by the gNB to indicate to the gNB when a QoE measurement session starts or stops for a certain application layer measurement configuration.

For a QoE measurement configuration, assistance information provided by OAM can be considered by the gNB for configuring a UE with a priority value. The priority value can be used by the UE to discard QoE measurement reports, as specified in TS 38.331 [12].