NEF controls the analytics exposure mapping among the AF identifier with allowed Analytics ID and associated inbound restrictions (i.e, applied to subscription of the Analytics ID for an AF) and/or outbound restrictions (i.e. applied to notification of Analytics ID to an AF).
In this Release, AF is configured with the appropriated NEF to subscribe to analytics information, the allowed Analytics ID(s) and with allowed inbound restrictions (i.e. parameters and/or parameter values) for subscription to each Analytics ID.
The AF subscribes to or cancels subscription to analytics information via NEF by invoking the Nnef_AnalyticsExposure_Subscribe
service operation defined in TS 23.502
. If the AF wants to modify an existing analytics subscription at NEF, it includes an identifier (Subscription Correlation ID) to be modified in the invocation of Nnef_AnalyticsExposure_Subscribe
, in addition, if the AF has taken an action(s) influenced by the previously received analytics information at step 4, which may or may not affect the ground truth data corresponding to Analytics ID requested at the time which the prediction refers to, the AF may include Analytics feedback information in the invocation of Nnef_AnalyticsExposure_Subscribe
. If the analytics information subscription is authorized by the NEF, the NEF proceeds with the steps below.
Based on the request from the AF, the NEF subscribes to or cancels subscription to analytics information by invoking the Nnwdaf_AnalyticsSubscription_Subscribe
If the parameters and/or parameters values of the AF request comply with the inbound restriction in the analytics exposure mapping, NEF forwards in the subscription to NWDAF service the Analytics ID, parameters and/or parameters values from the AF request.
If the request from AF does not comply with the restrictions in the analytics exposure mapping, NEF may apply restrictions to the subscription request to NWDAF (e.g. restrictions to parameters or parameter values of the Nnwdaf_AnalyticsSubscription_Subscribe
service operations), based on operator configuration and/or may apply parameter mapping (e.g. geo coordinate mapping to TA(s)/Cell-id(s)).
The NEF records the association of the analytics request from the AF and the analytics request sent to the NWDAF.
The NEF selects an NWDAF that supports analytics information requested by the AF using the NWDAF discovery procedure defined in TS 23.501
If the subscription relates to outbound roaming users, the NWDAF in the HPLMN may decide to retrieve or to subscribe to input data or analytics from the VPLMN.
If the AF request is for a modification of the existing analytics subscription(s), the NEF invokes Nnwdaf_AnalyticsSubscription_Subscribe
to modify the analytics subscription identified by an identifier (Subscription Correlation ID) associated with the AF.
If the NEF has subscribed to analytics information, the NWDAF notifies the NEF with the analytics information or Termination Request by invoking Nnwdaf_AnalyticsSubscription_Notify service operation.
If the NEF receives the notification from the NWDAF, the NEF notifies the AF with the analytics information or Termination Request by invoking Nnef_AnalyticsExposure_Notify
service operation defined in TS 23.502
. NEF may apply outbound restrictions to the notifications to AFs (e.g. restrictions to parameters or parameter values of the Nnef_AnalyticsExposure_Notify
service operation) based on analytics exposure mapping and may apply parameter mapping for external usage (e.g. TA(s), Cell-id(s) to geo coordinate). The AF checks if a Termination Request is present in the Nnef_AnalyticsExposure_Notify
as defined in step 2 in clause 220.127.116.11
When calculating the analytics/ML model accuracy information with the retrieved Analytics feedback information, in addition to comparing predictions of ML model and its corresponding ground truth data, the NWDAF may determine/take into account whether the action(s) taken by the AF affects the ground truth data corresponding to Analytics ID requested at the time which the prediction refers to or start rating AF(s) used as data sources, as described in clauses 6.2D
and 6.2E, which may affect the ML Model Accuracy monitoring.