A.15 Hybrid uplink and downlink media streaming using content preparation
26.5013GPP5G Media Streaming (5GMS)General description and architectureRelease 18TS
This scenario represents a hybrid end-to-end form of collaboration across uplink media streaming and downlink media streaming services. An external 5GMS Application Provider relies on the 5GMS System to support both the uplink streaming media transmission by 5GMSu Clients and subsequent distribution of that content via downlink media streaming for reception by 5GMSd Clients within the same 5GMS System.
Figure A.15-1: Hybrid uplink and downlink media streaming
Figure A.15-2 shows the call flow for this scenario. To simplify the call flow, the content preparation process is omitted.
Figure A.15-2: Call flow for hybrid uplink and downlink media streaming using content preparation
Steps:
1. The 5GMSd Application Provider creates a Provisioning Session with the 5GMSd AF (M1d).
2. The 5GMSd Application Provider provisions the 5GMSD AF with a Content Hosting Configuration.
3. The 5GMSdAF, based on the received Content Hosting Configuration, requests the 5GMSd AS to confirm the availability of distribution resources (M3d, procedures not specified).
4. The 5GMSd AF acknowledges to the 5GMSd Application Provider the successful creation of the Content Hosting Configuration (M1d).
5. The 5GMS Application Provider creates a Provisioning Session with the 5GMSu AF (M1u).
6. The 5GMSu AF requests the 5GMSu AS to confirm the uplink resources availability. (M3u, procedures not specified).
7. The 5GMSu AF acknowledges to the 5GMSu Application Provider of the successful provisioning (M1u).
At some later point in time:
8. The 5GMSu Application Provider provides Service Access Information to the 5GMS-Aware Application at reference point M8u.
9. The 5GMS-Aware Application requests the 5GMSu Client to start an uplink streaming session (M6u/M7u).
10. The 5GMSu Client requests that the 5GMSu AF initialises uplink media streaming (M5u).
Alternatively:
11. The 5GMS-Aware Application requests the 5GMSu Client to start an uplink streaming session (M6u/M7u).
12. The 5GMSu Client requests Service Access Information from the 5GSMu AF at reference point M5u.
At some later point in time:
13. If remote configuration and control is activated, the 5GMSu AF configures and controls the 5GMSu Client remotely (M5u).
14. Uplink media streaming starts from the 5GMSu Client to the 5GMSu-like AS (M4u′).
15. Media streaming egest starts from the 5GMSu-like AS to the 5GMSu Application Provider (M2u′).
16. If content preparation was provisioned in step 6, the uplinked media may be manipulated by the 5GMSu AS prior to being streamed to the 5GMSd AS.
17. The 5GMSu AS streams the content to the 5GMSd AS (I2, not specified).
Steps 18–22 concern the 5GMS downlink streaming process:
18. The 5GMS Application Provider optionally provides the service access information to the 5GMSd-Aware Application (M8d).
19. The 5GMS-Aware Application requests the 5GMSd Client to start an uplink streaming session (M6d/M7d).
20. If Service Access Information was not provided in step 14, the 5GMSd Client requests this information from the 5GSMd AF (M5d).
21. The 5GMSd Client requests the start of the downlink streaming session from the 5GSMd AF (M5d).
22. The downlink media streaming starts (M4d).
Finally:
23. The 5GMSu AS releases its uplink content preparation resources after observing a period of interactivity.
24. The 5GMSd AS releases its downlink content preparation resources after observing a period of interactivity.
NOTE: Steps 23 and 24 are implementation-dependent.
Annex B (informative):
MNO-specific Service Access Information acquisition