r network. 42 Chapter 1 NG-RAN supports differentiated handling of traffic for different network slices which have been preconfigured. The support of slice capabilities in terms of the NG-RAN functions (i.e., the set of NFs that comprise each slice) is implementation dependent. The NG-RAN supports the selection of the RAN part of the network slice by assistance information pro- vided by the UE or the 5GC which unambiguously identifies one or more preconfigured network slices in the PLMN. The NG-RAN supports policy enforcement between slices according to service-level agreements. It is possible for a single NG-RAN node to support multiple slices. The NG-RAN can apply the best RRM policy depending on the service agreements for each supported slice. The NG-RAN further supports QoS differentiation within a slice. For initial attach, the UE may provide assistance information to support the selection of an AMF and the NG-RAN uses this information for routing the initial NAS to an AMF. If the NG-RAN is unable to select an AMF using this information or the UE does not provide such information, the NG-RAN sends the NAS signaling to a default AMF. For subsequent accesses, the UE provides a Temp ID, which is assigned to the UE by the 5GC, to enable the NG-RAN to route the NAS message to the appropriate AMF as long as the Temp ID is valid. Note that the NG-RAN is aware of and can reach the AMF which is asso- ciated with the Temp ID. The NG-RAN supports resource isolation between slices via RRM policies and protection mechanisms that would avoid conditions such as shortage of shared resources in one slice resulting in under-service issues in another slice. It is possible to fully dedicate the NG- RAN resources to a certain slice. Some slices may be available only in certain parts of the network. Awareness in the NG-RAN of the slices supported in the cells of its neighbors may be beneficial for inter-frequency mobility in the connected mode. It is assumed that the slice configuration does not change within the UE's registratio