packets. For downlink transmission, the AMF sends the Downlink NAS Transport request with possibly a TAI restriction list and a paging priority indicator. If the NG-RAN node does not transmit the message, it informs the AMF via the NAS Non-Delivery Indication message. When a mobile makes an attachment request, the NG-RAN node transfers the message to a source AMF function. In the case of virtualization of network functions, and slicing of the network (Network Slicing), the choice of the radio node is defined on the basis of the information requested by NSSAI. 2.2.3.6. Global procedures Global procedures allow us to: - configure the NG-RAN nodes and the AMF function in order to ensure the full interoperability of the two entities (NG Setup message); - reinitialize the NG-RAN node in the event of a fault at the level of the radio node or of the 5GC core network via the NG Reset message; - update the configuration of the NG-RAN node and the configuration of the AMF function; - inform the radio node in the event of the start or end of AMF congestion. NG-RAN and 5G-NR 2.3. Identities of the XnAP and NG-AP application protocols An application protocol identity (AP ID) is allocated per mobile for each new logical connection creation on the NG-RAN interfaces: - RAN UE NGAP ID uniquely identifies for a gNB, the UE connection on the NG interface. The identity is created by the base station and is transmitted to the AMF entity; - AMF UE NGAP ID uniquely identifies the connection of the mobile on the NG interface for an AMF. The identity is created by the AMF function and is transmitted to the base station; - M-NG-RAN node UE XnAP ID uniquely identifies the mobile on the Xn interface in the case of dual connectivity. The identifier is created by the master base station and is transmitted to the secondary base station; - S-NG-RAN node UE XnAP ID uniquely identifies the mobile on the Xn interface in the case of dual connectivity. The identifier is created by the secondary base station and is transmitted to the master base stat