establishment or at the last tracking area update. 2. The source gNB configures the UE measurement procedures and the UE reports according to the measurement configuration. 3. The source gNB decides to handover the UE, based on measurement reports and radio resource management (RRM) information. The source gNB issues a Handover Request message to the target gNB passing a trans- parent RRC container with necessary information to prepare for the handover at the target gNB. The information includes target cell ID, KgNB*, C-RNTI of the UE in the source gNB, RRM configuration including UE inactive time, basic AS-configuration including antenna info and DL carrier frequency, the current QoS flow to DRB map- ping rules applied to the UE, the SIB1 from source gNB, the UE capabilities for differ- ent RATs, and PDU Session related information, and can further include the UE reported measurement information including beam-related information. The PDU Session related information includes the slice information (if supported) and QoS flow level QoS profile(s). After issuing a Handover Request, the source gNB should not reconfigure the UE, including performing reflective QoS flow to DRB mapping. Admission control may be performed by the target gNB. Slice-aware admission con- trol is performed, if the slice information is sent to the target gNB. If the PDU sessions are associated with non-supported slices, the target gNB would reject those PDU sessions. The target gNB prepares the handover with L1/L2 and sends the Handover Request Acknowledge to the source gNB, which includes a transparent container to be sent to the UE as an RRC message to perform the handover. 7. The source gNB triggers the Uu handover by sending an RRCReconfiguration message to the UE, containing the information required to access the target cell, that is, the tar- get cell ID, the new C-RNTI, and the target gNB security algorithm IDs for the selected security algorithms. It can also include a set of dedicated RACH resources, the association between RACH reso