A.6 UE Initiated UL QoS Flow

38.3003GPPNRNR and NG-RAN Overall descriptionRelease 17Stage 2TS

The following figure shows an example message flow when the UE AS receives an UL packet for a new QoS flow for which a QFI to DRB mapping rule does not exist.

Figure A.6-1: UL packet with a new QoS flow for which a mapping does not exist in UE

0. PDU session and DRBs (including a default DRB) have been already established.

1. UE AS receives a packet with a new QFI from UE NAS.

2. UE uses the QFI of the packet to map it to a DRB. If there is no mapping of the QFI to a DRB in the AS mapping rules for this PDU session, then the packet is assigned to the default DRB.

3. UE sends the UL packet on the default DRB. The UE includes the QFI in the SDAP header.

4. gNB sends UL packets to UPF and includes the corresponding QFI.

5. If gNB wants to use a new DRB for this QoS flow, it sets up one. It can also choose to move the QoS flow to an existing DRB using RQoS or RRC signalling (see clauses A.2 and A.3).

6. User Plane Data for the new QoS flow can then be exchanged between UE and gNB over the DRB according to the updated mapping rules and between UPF and gNB over the tunnel for the PDU session.

Annex B (informative):
Deployment Scenarios