of SAEGW Downlink Data Uplink Data SECONDARY RATE DATA USAGE REPORT Figure 10.10 - Option 3x call flow part 3 16. The SAEGW-C then sends the PFCP: Session Modification Request message to the SAEGW- U. This message contains the F-TEID information received from the eNB. The user plane then sends the PFCP: Session Modification Response with the F-TEID of the user plane. 17. The SAEGW-C then sends the Modify Bearer Response to the MME with the F-TEID information, which is sent to the radio. 18. Once the tunnel information is exchanged, the data path is set up and the UE can access it. The following call flow indicates the addition of a 5G secondary node. 19. The master eNB sends an RRC Connection Reconfiguration message to the UE. This message assigns radio resources to the UE: 5G NSA - option 3 call flows 5G secondary node addition LTE-5GNR UE LTE eNodeB 5G-NR gNodeB 4G Core Network MN-eNB SN-gNB 43: RRC Connection Reconfiguration (SRB3, DRB) nr-Config-r15, endc-ReleaseAndAdd-r15, nr-SecondaryCell GroupConfig-r15=CG-Config, hr-RadioBearerConfig-r15=NR-RRCRadioBearerConfig -cellGroupID, -rlc-Bearer ToAddModList, -mac-CellGroupConfig, -physicalCellGroupConfig, -reconfigurationWithSync = (newUE-Identity C-RNTI), -rif-TimersAndConstants, -riminSyncOutOfSyncThreshold, -spCellConfigDedicated, p_MaxEUTRA-r15, -sk-Counter-r15, -nr-RadioBearerConfig1-r15, -nr-RadioBearerConfig2-r15, -tdm-PatternConfig-r15, -nonCriticalExtension Extract NR information from LTE RRC Connection Reconfiguration 44:UE extracts NR RACH configuration information 45:Extract C-RNTI from'new UE Identity' in the 'reconfigu- ration With Sync' IE 46:P repare the NR RRC Reconfiguration Complete message 47: RRC Connection Reconfiguration (SRB3, DRB) scg-ConfigResponseNR-r15= NR RRCReconfiguration Complete 48: X2AP SgNB Reconfiguration Complete MeNB to SgNB Container = NR RRCReconfiguration Complete eNodeB starts copying data to the gNodeB 49: SN Status Transfer PDCP SN, HFN 50: Data 50: Data begin 51: Buffering data 5G Non-Standalone Networks Path update pr