Section: 5.2.21.4.2 Nnsacf_SliceEventExposure_Subscribe service operation
Content: Service operation name: Nnsacf_SliceEventExposureSubscribe Description: This service operation is used by the consumer NF to subscribe or modify a subscription with the NSACF for event based notifications of the current number of UEs registered for a network slice or the current number of PDU Sessions established on a network slice. Inputs, Required: Event ID, Event Filter, Event Reporting information. The Event ID parameter defines whether to notify the number of UEs registered with a network slice or the number of PDU Sessions established on a network slice. The Event Filter parameter is the S-NSSAI for which the current number of UEs registered for a network slice or the current number of PDU Sessions established on a network slice or both are to be notified to the consumer NF. The Event Reporting information parameter defines whether the notification is threshold based (e.g. the notification is triggered when the current number of UEs or PDU Sessions with a network slice reaches a defined threshold value) or the notification is periodical (e.g. the notification is triggered at expiry of a periodic timer) and optionally the Immediate reporting flag. Inputs, Optional: Notification threshold, Notification periodicity. The Notification threshold parameter is optional. It is provided when the Notification is threshold base. The notification threshold parameter may be a numeric value or a percentage of the maximum number of the UEs or PDU Sessions per network slice. The Notification periodicity parameter is optional. It is provided when the Notification is periodical. The Notification periodicity parameter defines the time between the notification periodicity. Outputs, Required: Operation execution result response, Subscription Correlation Id.