The UE is notified about the 5G bearer via the RRC Connection Reconfiguration message. The UE then connects to the 5G network while maintaining the connectivity to the 4G network .
Read moreWhat is the difference between the RRC IDLE and the RRC inactive state?
When UE is power up it is in Disconnected mode/Idle mode, It can move RRC connected with initial attach or with connection establishment. If there is no activity from UE for a short time, It can suspend its session by moving to RRC Inactive and can resume its session moving to RRC connected mode .19 Kas 2017
Read moreWhat does RRC mean in LTE?
3GPP LTE RRC (Radio Resource Control ) Layer.
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