allocation of the QoS flow to a DRB is shown in Figure 3.4.8. 0. UE is registered with the network, and PDU sessions and DRBs are established to send data between UE and the network. 1. gNB receives a new data packet with a new QFI marking. 2. gNB decides to send this QoS flow on an existing DRB that meets the QoS requirement and to use AS reflective mapping. 3. gNG sends the data packet on the chosen DRB with the QFI and RQI bit set in the SDAP header. 3 5G System Overview 0. PDU session and DRB established 1. NG-U: DL packet [New QFI] 2. gNB decides to reuse an existing DRB to send this QoS flow 3. User plane: DL packet [LCID, QFI, RQI] 4. UE updates it DRB mapping table with new QFI 5. User plane data over DRB [QFI] 5. PDU data tunnel [QFI] Figure 3.4.8 An example signaling for a UE configuration of the DRB mapping for a new QoS flow using AS reflective mapping. 4. UE, upon receipt of the packet with the RQI bit set, updates the mapping table to send UL data with this QFI on this DRB. 5. Data for this QoS flow are exchanged over the DRB. 3.4.5 NR Control Plane RRC (specified in 3GPP TS 38.331) is control-plane protocol used to configure and manage the radio interface connection. RRC provides a set of procedures that are used for connec- tion establishment, security configuration, mobility, physical layer, and user-plane config- urations. 3.4.5.1 RRC States RRC supports three different UE states: CONNECTED INACTIVE. The IDLE and CONNECTED states are similar to LTE. A UE in active communication exchanging data with the network will be in the CONNECTED state. In this state, phys- ical channels and user-plane protocols are configured and set up. UE mobility is controlled by the network using RRC messages. A UE context is created in the RAN when the UE moves to the RRC CONNECTED state. The UE context includes the information about the connection to the CN, the user plane, and physical layer configurations. The UE context is cleared when the UE leaves RRC CONNECTED and goes back to RRC IDLE. A UE is in IDLE or INACT