The procedures for uplink media streaming allow a 5GMSu Application Provider to create, modify, establish and delete sessions. Uplink media streaming sessions exist between a 5GMSu Client and a 5GMSu AS. The uplink streaming procedures follow a general high-level workflow, starting from provisioning to the actual uplink streaming sessions. The Egest Session refers to the time period during which media content is uplink streamed to the 5GMSu AS and optionally egested from there to the 5GMS Application Provider. The Provisioning Session refers to the time period during which the 5GMSu Client is permitted to upload stream media content. Interactions between the 5GMSu AF and the 5GMSu Application Provider may occur at any time while the Provisioning Session is active. The 5GMSu Provisioning API allows the selection of Media Session Handling (M5u) and Uplink Streaming (M4u) options, including whether the media content is published to trusted 5GMSu ASs. The 5GMSu AF selects the M5u interface according to the provisioning option. The Media Session Handling interface exposed by the 5GMSu AF can be used for metrics reporting, requesting different policy and charging treatments, or 5GMSu AF-based Network Assistance. When the 5GMSu AF and 5GMSu AS reside in the same DN, then the 5GMSu AF selects the 5GMSu AS. Interactions between a 5GMSu AF and a 5GMSu AS (M3u interactions) take place for Content Egest (M2u) and Uplink Streaming (M4u) resource reservations. The 5GMSu AS allocates M2u and M4u resources and communicates resource identifiers back to the 5GMSu AF. The 5GMSu AF provides information about the provisioned resources (in the form of resource identifiers) for Media Session Handling, Content Egest, and Uplink Streaming to the 5GMSu Application Provider. The resource identifiers for Media Session Handling and Uplink Streaming are needed by the 5GMSu Client to access the selected features. 5GMSu Client can (in principle) start the uplink streaming by activating its uplink streaming session. The uplink streaming session for a given UE (or for each UE) is active from the time at which the 5GMSu-Aware Application activates the transmission of an uplink streaming service until its termination. The 5GMSu-Aware Application receives application metadata from the 5GMSu Application Provider before transmitting the uplink streaming media. The application metadata contains Service Access Information, which acts as an entry point for the 5GMSu Client to start the uplink streaming session. The 5GMSu Client may either receive the Service Access Information from the 5GMSu Application Provider (using a not standardized interface) or instructions for a remote control session through the 5GMS-Aware Application. The Network Assistance (NA) feature enables a UE that is receiving an uplink media stream to improve the QoE of the media streaming session, by being able to make use of two distinct facilities. The first facility is bit rate recommendation (throughput estimation). This enables the UE to start an uplink streaming session at the most appropriate bit rate for the network conditions at hand, or to obtain a recommendation from the network which will remain valid until further notice during a media streaming session. The recommended bit rate is based on network estimations or predictions of available link bandwidth. This function is provided as an additional tool to support the UE, in addition to the common approach of the UE performing its own estimation based on measurement of the uplink traffic in the past. The second facility is the delivery boost. The 5GMSu Client uses this function to indicate to the network that a temporary boost, i.e., a temporary increase of network throughput for this client is needed, for example in order to prevent the uplink media streaming buffer in the Media Streamer from overflowing. Network Assistance may be offered to the UE in one of two ways:

• Based on interaction between the UE and the 5GMSu AF, with a subsequent interaction between the 5GMSu AF and the PCF (or the NEF), as defined in clause 6.5.
• Based on interaction between the UE and the RAN, re-using the ANBR-based RAN signalling as defined in clause 6.7.

The UE shall not use both approaches on the same Network Assistance session. Figure 6.1-1 provides a basic high-level call flow for uplink streaming. The corresponding collaboration scenario is defined in clause A.10.

Steps: At some later point in time: Alternatively: Then: Clauses A.11 to A.15 define additional collaboration scenarios for uplink streaming. The call flow for each collaboration scenario is also included in each clause.