5G • Core Network
Session-AMBR
Session Aggregate Maximum Bit Rate
Maximum aggregate bit rate allowed across all Non-GBR QoS flows within a single PDU session.
Technical Explanation
Session-AMBR is subscribed in UDM and enforced by the UPF in the downlink and UE/UPF in the uplink. It caps the cumulative bandwidth of all best-effort flows (browsing, background sync, downloads) belonging to that specific PDU session, regardless of momentary radio capacity.
Key Functions
- Caps aggregate bandwidth across all non-GBR flows in a single PDU session
- Enforced by the UPF in downlink and UE/UPF in uplink
- Configured per subscriber subscription profile in UDM
Specifications
3GPP TS 23.501
Interfaces
N4N1
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