4.9 User consent handling in MDT for NG-RAN

32.4223GPPRelease 17Subscriber and equipment traceTelecommunication managementTrace control and configuration managementTS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

4.9.1 Signalling based MDT

In case of signalling based MDT getting user consent before activating the MDT functionality is required because of privacy and legal obligations. It is the Operator responsibility to collect user consent before initiating an MDT for a specific IMSI, IMEI number or SUPI.

Collecting the user consent shall be done via customer care process. The user consent information availability should be considered as part of the subscription data and as such this shall be provisioned to the UDM database.

The following figure summarizes the functionality.

Figure 4.9.1.1: Example for delivering user consent information in signalling based MDT

When the IMSI/IMEI(SV)/SUPI based MDT is activated it is targeted the UDM. Once the user consent availability information is stored in the UDM database, the UDM can check the user consent availability before starting a Trace Session for the given subscriber. If there is no user consent given by the specific user to network where TCE resides, the UDM should not start a Trace Session for the given subscriber.

As the user consent availability information is stored as part of the subscription data it should also be transferred to the AMF during update location procedure. This is required if the signalling based MDT is started from AMF. In that case similar checking is required as in the UDM case.

It should also be possible to handle user consent revocation. The process of user consent revocation shall be done also via customer care process and the user consent availability information should be updated in the UDM DB when a user consent revocation happens.

If the user consent revocation happens during an ongoing Trace Session with MDT, it is not required to stop and deactivate the Trace Recording Session, Trace Session respectively immediately i.e. to stop an ongoing Trace Recording Session in case of Immediate MDT. A notification to the management system should be sent and the management system should deactivate the Trace Session.

4.9.2 Management based MDT

The following figure summarizes the functionality.

Figure 4.9.2.1: Example for delivering user consent information in management based MDT

When UE attaches to the network, the UDM shall forward the user consent information, stored in the UDM database, to the corresponding AMF. When the AMF receives the user consent information it shall store it in its subscriber database.

The AMF shall also check the roaming status of the user. If the user is within its home operator’s PLMNs and the user has given its consent, the AMF shall send the Management based MDT PLMN List IE to the gNB during the UE context setup procedure (INITIAL CONTEXT SETUP REQUEST message, see TS 38.413 [49]). Otherwise the AMF shall not send the Management based MDT PLMN List IE to the gNB.

If the result of the roaming status check indicates a home subscriber, AMF shall forward the already stored user consent information to the corresponding gNB as part of Management based MDT PLMN List IE .

When the management based MDT activation is sent to gNB, gNB shall check the availability of the Management based MDT PLMN List IE before making the UE selection. In case the Management based MDT PLMN List IE is not available, the gNB shall not select the UE. In case the Management based MDT PLMN List IE is available, the gNB shall verify if the UE’s RPLMN matches the PLMN where TCE resides – Trace Reference PLMN (PLMN portion of the Trace Reference). In case of a mismatch, the gNB shall not select the UE. The gNB shall forward the received Management based MDT PLMN List IE during Xn based handovers to the target node. The Management based MDT PLMN List IE is stored in the gNB as part of the UE context. If the user consent information is updated while a UE context is already set up in the gNB, the changed user consent should be taken into account in the next call/session setup.

The AMF shall forward the received Management based MDT PLMN List IE during N2 based handovers to the target node in the HANDOVER REQUEST message. Furthermore, in case of path switch request procedure, the AMF shall forward the received Management based MDT PLMN List IE to the corresponding gNB in PATH SWITCH REQUEST ACKNOWLEDGE message, see TS 38.413 [49].

AMF subscribes to UDM SDM API to get notification on any changes of the UE AM subscription data, including the changes on MDT user consent information which is part of the UE AM subscription data. When being notified by the UDM about an MDT user consent information change, the AMF shall subsequently signal the updated Management Based MDT PLMN Modification List IE to the gNB in UE CONTEXT MODIFICATION REQUEST message, see TS 38.413 [49].