5G • 5G-Advanced (Rel-18)
XR Frame PDB
Frame-Level Packet Delay Budget Allocation
QoS enhancement in Rel-18 where the Packet Delay Budget is enforced across the entire video frame rather than on isolated individual IP packets.
Technical Explanation
Standard 5G QoS enforces Packet Delay Budgets (PDB) independently on every IP packet. In video streaming, if 99 packets arrive in 5 ms but the 100th packet is delayed past the 15 ms frame deadline, the entire video frame is discarded by the decoder, wasting radio resources. Rel-18 Frame PDB schedules packets collectively to ensure 100% of the frame arrives within the budget.
Key Functions
- Enforces latency constraints across the complete collection of packets in a video frame
- Prevents transmission of trailing packets when a video frame has already missed its deadline
- Saves cellular radio bandwidth by flushing useless stale frame fragments from buffers
- Guarantees deterministic end-to-end latency for interactive cloud gaming and AR
Specifications
3GPP TR 38.835, TS 23.501 (Rel-18)
Interfaces
UuN3N6
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