Feature Description
The N3 transfer of PDU session information involves the inclusion of QoS Field Identifier (QFI) IE in the GTP-U extension header while performing GTP-U encapsulation toward gNodeB on the N3 interface, and removal of the GTP-U extension header while performing GTP-U decapsulation when packets are received from the gNodeB.
The QFI IE detects traffic pertaining to specific QoS sessions. It is used to send control information between the gNodeB and the UPF.