Section: 6.2.5.1.1.4 QoS flow descriptions
Content: The network can also provide the UE with one or more QoS flow descriptions associated with a PDU session at the PDU session establishment or at the PDU session modification. Each QoS flow description contains: a) a QoS flow identifier (QFI); b) if the flow is a GBR QoS flow: 1) Guaranteed flow bit rate (GFBR) for UL; 2) Guaranteed flow bit rate (GFBR) for DL; 3) Maximum flow bit rate (MFBR) for UL; 4) Maximum flow bit rate (MFBR) for DL; and 5) optionally averaging window, applicable for both UL and DL; c) 5QI, if the QFI is not the same as the 5QI of the QoS flow identified by the QFI; and d) optionally, an EPS bearer identity (EBI) if the QoS flow can be mapped to an EPS bearer as specified in subclause 4.11.1 of 3GPP TS 23.502[ Procedures for the 5G System (5GS) ]  [9]. If the averaging window is not included in a QoS flow description for a GBR QoS flow with a 5QI indicated in 3GPP TS 23.501[ System architecture for the 5G System (5GS) ]  [8] table 5.7.4-1, the averaging window associated with the 5QI in 3GPP TS 23.501[ System architecture for the 5G System (5GS) ]  [8] table 5.7.4-1 applies for the averaging window. If the averaging window is not included in a QoS flow description for a GBR QoS flow with a 5QI not indicated in 3GPP TS 23.501[ System architecture for the 5G System (5GS) ]  [8] table 5.7.4-1, the standardized value of two seconds is used as the averaging window.