5G Qos management is more complex than the simple QoS mapping of LTE EPS bearer.
The 5G QoS model is based on the QoS flow. The QoS flow is the best granularity for differentiating QoS differences in the PDU session and is uniquely identified by the QoS flow ID (QFI), which allow adapting to various services.
The 5GC maps the service package to the QoSFlow, and the NG RAN maps the QoSFlow to the DRB on the air interface. to ensure the service quality.
The 5GC establishes one or more PDU sessions for each UE. One or more QoSflows may be established in the PDU session. In the same PDU dialog, the NG-RAN establishes different DRBs for QoSflows with different requirements or maps multiple QoSflows with the same QoSrequirements to the same DRB.
- The 5G QoSarchitecture applies only to the SA networking scenario
- The QoS object of 5G is PDU Session/QoSFlow, and that of 4G is E-RAB.
- The 5G uses the QoS Flow granularity for QoS control. The 4G uses the EPS Bearer for QoS control.