QoS Enforcement
The SMF enforces QoS at PCC rule (SDF) level, QoS flow level, and session level by creating one QER:
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per PCC rule level to enforce MBR/GBR as per the associated QoS Desc supplied by PCF and associated to the given PCC rule.
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at QoS flow level which has aggregated MBR/GBR of all the PCC rules associated with a QFI.
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at session level to enforce the Session AMBR for all non-GBR QoS flows.
Once these QERs are created, the SMF associates:
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the session level QER to all PDRs belonging to the non-GBR QoS category.
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the SDF level QER to each individual PCC rule.
For any QoS modification including movement of the PCC rules from one flow to another and QoS modification within flow, the SMF modifies the GFBR/MFBR (or Session AMBR) and updates the QERs accordingly on the N4 interface.