Transfer of PDU Session Information for Downlink Data Packets

The Transfer of PDU Session Information for downlink data packets involves transfer of control information elements related to the PDU Session from UPF/NG-RAN to NG-RAN.

A PDU session user plane instance that makes use of this transfer procedure is associated to a single PDU Session. The procedure is invoked whenever packets for that particular PDU Session must be transferred across the related interface instance.

The DL PDU SESSION INFORMATION frame includes a QoS Flow Identifier (QFI) field that is associated with the transferred packet. The NG-RAN uses the received QFI to determine the QoS flow and QoS profile which are associated with the received packet.

The following frame shows the respective DL PDU SESSION INFORMATION.

NOTE: In current implementation, the Reflective QoS Indicator (RQI) and Paging Policy Presence (PPP) in DL PDU SESSION INFORMATION frame is not supported.