Tech-invite  3GPPspace  IETFspace
21  22  23  24  25  26  27  28  29  31  32  33  34  35  36  37  38  4‑5x

Content for  TS 26.501  Word version:  18.6.0

Top   Top   Up   Prev   Next
1…   4…   4.0.6…   4.1…   4.2…   4.2.2…   4.3…   4.4   4.5…   4.6…   4.7…   4.7.4…   4.8   4.9…   4.10…   5…   5.2…   5.2.4   5.2.5…   5.3…   5.3.2…   5.4…   5.5…   5.6…   5.7…   5.7.4…   5.7.8   5.8…   5.10…   5.10.5…   5.10.6…   5.11…   5.12…   5.12.4…   5.12.5…   6…   6.2…   6.2.2.2…   6.2.3…   6.3…   6.4…   6.8…   6.9…   6.9.5…   6.9.7   7…   8…   9…   A…   A.4…   A.8   A.9   A.10   A.11   A.12   A.13   A.14   A.15…   A.15.3…   B…   B.3   C…   C.3   C.4   C.5   D…   E… 
5.7.4 DASH Streaming  5.7.5 Parameters for dynamic policy invocation configuration  5.7.6 Dynamic Policy selection for downlink media streaming based on Service Operation Point signalling  5.7.7 Use of Service Operation Point signalling to optimise delivery of low-latency live media streaming services (informative)  5.7.7.1 5GMS System acts as a CDN  5.7.7.2 5GMSd AS deployed in an external DN 
...

 

5.7.4  DASH Streaming  p. 108

It is assumed here that the key information to initialize the media decoding and rendering pipeline is present in the Media Player Entry (or referenced by the Media Player Entry). The intention is to provide the client with information to setup the media decoding and rendering pipeline in such a way that no pipeline reset is needed during the session. Implementations need to consider that parts of the information are provided with the initialization segments.
It is assumed that the client is enabled to use the same media decoding and rendering pipeline during the session.
Copy of original 3GPP image for 3GPP TS 26.501, Fig. 5.7-2: High Level Procedure for DASH content
Figure 5.7-2: High Level Procedure for DASH content
(⇒ copy of original 3GPP image)
Up
Prerequisites:
  • The 5GMSd Application Provider has provisioned the 5G Media Streaming System and has set up content ingest.
  • The 5GMSd-Aware Application has received the service announcement from the 5GMSd Application Provider.
  • The Service Announcement Information contains detailed information for the policy related interactions. Specifically, the information includes URLs for the 5GMSd AF, an identifier of the Provisioning Session and a list of authorized Policy Type indications for that specific application.
  • The 5GMSd Application Provider has agreed an SLA with the Network Operator defining the possible QoS levels and their charging rates (see clause 6.1.3.22 of TS 23.503). The PCF is configured with the corresponding QoS parameters and charging information.
Steps:
Step 1.
The 5GMSd-Aware Application triggers the Service Announcement and Content Discovery procedure. The Content Discovery procedure only involves the App 5GMSd-Aware Application and the 5GMSd Application Provider. The Service Announcement includes either the whole Service Access Information (i.e. details for Media Session Handling (M5d) and for Media Streaming access (M4d)) or a reference to the Service Access Information. The configuration parameters are listed in Table 5.7.4-1.
Step 2.
A media content item is selected.
Step 3.
The 5GMSd-Aware Application triggers the Media Session Handler to start media playback. The Media Player Entry is provided to the Media Session Handler.
Step 4.
When the 5GMS-Aware Application has received only a reference to the Service Access Information (see step 1), the Media Session Handler interacts with the 5GMSd AF to acquire the whole Service Access Information.
Step 5.
The Media Session Handler triggers the Media Player to start the session.
Step 6.
The Media Player establishes a transport session for acquiring the MPD referenced by the Media Player Entry.
Step 7.
The Media Player requests the MPD.
Step 8.
The Media Player receives the MPD.
Step 9.
The Media Player processes the MPD. It determines, for example, the number of needed transport sessions for media acquisition. The Media Player should be able to use the MPD information to initialize the media pipelines for each media stream. The MPD should also contain information to start the DRM client initialization, when DRM is used.
Step 10.
The Media Player notifies the Media Session Handler about the MPD. The notification may contain parameters from the MPD.
Step 11.
(Optional) the Media Player acquires the necessary DRM information, for example a DRM License.
Step 12.
The Media Player configures the media rendering pipeline.
Step 13.
The Media Player establishes the necessary transport session(s) for acquiring the content. For example, the Media Player may establish one transport session for each media component (audio, video, etc) and possibly additional transport sessions for other media representations.
Step 14.
The Media Session Handler is notified about the established transport session(s) for the content by providing the Service Data Flow Description of the application flows as defined in the Service Access Information. This can be for example 5-tuples.
Step 15.
The Media Session Handler requests that a dynamic policy be applied to the media session. The request includes at least the Provisioning Session identifier, the Service Data Flow Description(s) and the Policy Template identifier (see Table 5.7.4-1), to be applied to the described transport session. In some cases, a QoS specification is also provided, containing desired QoS information. The 5GMSd AF uses the Policy Template for the related procedure and to identify the related network function.
Step 16.
This step applies when the 5GMSd AF resides in the trusted Data Network. Depending on the Policy Template, the step is executed either:
  1. When the Policy Template relates to QoS, the 5GMSd AF may either directly interact with the PCF or may use a NEF service:
    • when directly interacting with the PCF, the 5GMSd AF uses the Npcf_PolicyAuthorization service as defined in clause 5.2.5.3 of TS 23.502).
    • when interacting via the NEF with the PCF, continue at step 17a.
  2. When the Policy Template relates to a different charging scheme, the 5GMSd AF may either directly interact with the PCF or may use a NEF service:
    • when directly interacting with the PCF, the 5GMSd AF uses the Npcf_PolicyAuthorization service as defined in clause 5.2.5.3 of TS 23.502).
    • when interacting via the NEF with the PCF, continue at step 17b.
Step 17.
This step applies when the 5GMSd AF resides in the external Data Network. Depending on the Policy Template, the step is executed either:
  1. When the Policy Template relates to QoS, the 5GMSd AF may use the Nnef_AFsessionWithQoS service as defined in clause 5.2.6.9 of TS 23.502. (The complete call flow is described in clause 4.15.6.6 of TS 23.502.)
  2. When the Policy Template relates to a different charging scheme, the 5GMSd AF may use the Nnef_ChargeableParty service as defined in clause 5.2.6.8 of TS 23.502. (The complete call flow is described in clause 4.15.6.4 and clause 4.15.6.5 of TS 23.502.) The Policy Template may contain the Sponsor Information (values, based on SLA negotiation) and Background Data Transfer Reference ID. The Flow Description is provided by the Media Session Handler at API invocation.
Step 18.
The Media Session Handler queries the status of the dynamic policy invocation. The response contains status information (policy accepted, rejected, etc) and information on policy enforcement such as the enforcement method and enforcement bit rate.
Step 19.
The Media Session Handler updates the configuration of the Media Player according to the response from the 5GMSd AF (See Table 5.6.4-2).
Step 20.
The Media Player requests a DASH initialization segment. The Media Player repeats this step for each required initialization segment.
Step 21.
The Media Player receives the initialization segments.
Step 22.
The Media Player requests DASH media segments according to the MPD.
Step 23.
The Media Player receives media segments and feeds them into the appropriate media rendering pipeline.
Step 24.
Previous steps are repeated according to the MPD information.
Up

5.7.5  Parameters for dynamic policy invocation configuration  p. 110

Parameters Description
Policy EnforcementInformation about the policy enforcement system.

5.7.6  Dynamic Policy selection for downlink media streaming based on Service Operation Point signalling |R18|  p. 111

This clause provides an extension to the general call flow in clause 5.2.3 in order to address the usage of Service Descriptions to select a Dynamic Policy in downlink 5G Media Streaming services that supports the requirements of an abstract Service Operation Point. Details are shown in Figure 5.7.6-1.
Copy of original 3GPP image for 3GPP TS 26.501, Fig. 5.7.6-1: High-level procedure for DASH content streaming
Figure 5.7.6-1: High-level procedure for DASH content streaming
(⇒ copy of original 3GPP image)
Up
with Service Operation Point handling
Prerequisites:
  • The 5GMSd Application Provider has provisioned the content hosting feature in the 5G Media Streaming System.
  • The 5GMSd-Aware Application has received the Service Announcement from the 5GMSd Application Provider.
Extended Steps:
Step 1.
Policy Templates are provisioned in the 5GMSd AF.
Step 12.
The Media Player informs the 5GMS-Aware Application about the set of Service Descriptions associated with the Media Player Entry document for the content selected in step 3. Each Service Description is identified by a different External reference.
Step 13.
The 5GMSd-Aware Application selects one of the available Service Descriptions.
Step 14.
The Media Player provides the External reference of the selected Service Description to the Media Session Handler.
Step 15.
The Media Session Handler selects a Dynamic Policy with a matching External reference.
Step 21.
The Media Player provides Operation Point metrics to the Media Session Handler.
Step 22.
The Media Session Handler sends Service Operation Point measurements and events to the 5GMSd AF.
Up

5.7.7  Use of Service Operation Point signalling to optimise delivery of low-latency live media streaming services (informative) |R18|  p. 112

5.7.7.1  5GMS System acts as a CDN  p. 112

In this case, the specific aspects are as follows:
  1. A provisioning agreement is struck between the 5GMSd Application Provider and the operator of the 5GMS System in the form of one or several Service Operation Points expressed as Service Descriptions and/or Policy Templates. (Service Descriptions may be derived from Policy Templates if the latter are omitted, or vice versa.)
  2. DASH or HLS content is provided externally. Media Entry Point documents are annotated with Service Descriptions. The content is published to the 5GMS System for distribution over downlink media streaming.
  3. Content is ingested by the 5GMSd AS at reference point M2d such that the latency requirements can be met.
  4. The 5GMS System distributes the ingested content according to the provisioning agreement, i.e. meeting bit rate and latency requirements of the agreed Service Operation Point.
  5. The Service Operation Point metrics collated by the 5GMSd AF are used by the 5GMS System to determine whether the agreed Service Operation Point has been satisfied, or whether the Policy Templates need to be adjusted so that it can be satisfied.
For low-latency streaming where the 5GMS System acts as a CDN, the basic call flow documented in clause 5.7.6 is extended as follows.
Extended steps:
Step 1.
Policy Templates suitable for supporting low-latency media streaming are provisioned in the 5GMSd AF.
Step 2.
Media ingest supports a low-latency protocol, e.g. segment content is provided in chunks.
Step 14.
5GMSd-Aware Application selects a low-latency Service Description and provides its External reference to the Media Session Handler.
Step 17.
The Media Player configures itself for low-latency playback based on the low-latency Service Description selected in step 14.
Step 21.
The Media Player operates in a low-latency media delivery mode.
Up

5.7.7.2  5GMSd AS deployed in an external DN  p. 113

In this case, the specific aspects are as follows:
  1. A provisioning agreement is struck between the 5GMS Application Provider and the operator of the 5GMS System in the form of one or several Service Operation Points expressed as Service Descriptions and/or Policy Templates. (Service Descriptions may be derived from Policy Templates if the latter are omitted, or vice versa.)
  2. The 5GMSd AS external.
  3. Content ingest by the 5GMSd AS is out of scope.
  4. The 5GMS System distributes the content according to the agreed provisioning agreement, i.e. meeting bit rate and latency requirements of the agreed Service Operation Point.
  5. The Service Operation Point metrics collated by the 5GMSd AF are used by the 5GMS System to determine whether the agreed Service Operation Point has been satisfied, or whether the Policy Templates need to be adjusted so that it can be satisfied.
For low-latency streaming where the 5GMSd AS is deployed in an external DN, the basic call flow documented in clause 5.7.6 is extended as follows.
Extended steps:
Step 1.
Policy Templates suitable for supporting low-latency media streaming are provisioned in the 5GMSd AF.
Step 14.
5GMSd-Aware Application selects a low-latency Service Description.
Step 17.
The Media Player configures itself for low-latency playback based on the low-latency Service Description selected in step 14.
Step 21.
The Media Player operates in a low-latency media delivery mode.
Up

Up   Top   ToC