D or DNN Information PDU session status SUPI or GPSI PDU session ID, DNN, or UE IP address SUPI or GPSI PDU session ID, DNN, or UE IP address N6 traffic routing information SUPI or GPSI PDU session ID, DNN, or UE IP address Figure 3.15 - Exposure data stored in the UDR The UDR offers the following services to its network function consumers: NF service Service Operations Operation Semantics Example Consumer(s) Data Management (DM) Query Request/Response UDM, PCF, and NEF Create Request/Response Delete Request/Response Update Request/Response UDM, PCF, and NEF Subscribe Subscribe/Notify UDM, PCF, and NEF Unsubscribe UDM, PCF, and NEF Notify UDM, PCF, and NEF GroupIDmap Query Request/Response NRF and SCP Figure 3.16 - Services offered by the UDR Let us go over the various service operations provided by the UDR, per 3GPP Release 16, 23.502: REST in 5G The Nudr_DataManagement service operation, Nudr_DM_Query, is used by a requesting consumer to request a set of data from the UDR. The query contains the key that is used to retrieve the record from the database. The Nudr_DM_Create service operation is used to create a new entry in the UDR. Hence, the service consumers can use this to insert a new record into the database. The Nudr_DM Delete Nudr_DM_Update service operations are used by the network function consumer to respectively delete or update an existing record in the UDM. The Nudr_DM_Subscribe service operation is used by the network consumer to subscribe to be notified of any changes or additions to the subscription data. The consumer can also unsubscribe using the Nudr_DM_Unsubscribe service. The Nudr_DM Notify service operation is used by the UDR to notify the subscribed network consumers about any change in subscription information. The Nudr_GroupIDmap_query service operation is used by the UDR to allow the retrieval of an NF group ID of a particular subscriber. AUSF services The AUSF services are used to provide a UE authentication service to the requesting network function. The following table describes the 