Question: What information does the source gNB include in the Source eNB to Target eNB Transparent Container during the handover preparation phase from 5GS to EPS with the Source Node used as target Secondary Node?
Option 1: The Source NG-RAN node ID and the RAN UE NGAP ID.
Option 2: The target en-gNB ID and the X2 SgNB Addition Request message.
Option 3: The DL UP data for the SN terminated bearers.
Option 4: The handover procedure details.
Explanation: During the inter-system handover from 5GS to EPS with the Source Node used as target Secondary Node, the source gNB triggers the handover preparation phase and includes the Source NG-RAN node ID and the RAN UE NGAP ID in the Source eNB to Target eNB Transparent Container. This information is necessary for the target eNB to identify the correct target en-gNB and perform the X2AP SgNB Addition procedure.