Content for TS 26.502 Word version: 17.3.0
5.3 Procedures for User Service provisioning p. 38
The procedure begins with the MBS Application Provider provisioning an MBS User Service and, within its scope, a set of MBS User Data Ingest Sessions, as shown in Figure 5.3-1 and Figure 5.3-2 below.
Figure 5.3-1: Call flow for MBS User Service provisioning by MBS Application Provider
(⇒ copy of original 3GPP image)
(⇒ copy of original 3GPP image)
First, the MBS Application Provider provisions a new MBS User Service Session in the MBS System:
Step 1.
Immediately, or at some later time, the MBS Application Provider creates at least one MBS User Data Ingest Session (as defined in clause 4.5.5) within the scope of the MBS User Service created in step 2 above:
To support Use Cases (e.g. Group Communication) where there is a requirement for TMGI allocation to be managed outside the MBS System, the MBS Application Provider may pre-allocate a TMGI for some or all of the MBS Distribution Sessions declared in step 3 below by invoking the Nmbsmf_TMGI_Allocate service operation on the MB-SMF at reference point Nmb13 (or N33+N29mb, if invoked via the NEF), as specified in clause 9.1.2.2 of TS 23.247.
Step 2.
The MBS Application Provider invokes the Nmbsf_MBSUserService_Create service operation at reference point Nmb10 (or N33+Nmb5 if invoking via the NEF) to create a new MBS User Service, as defined in clause 4.5.3.
Step 3.
Shortly before a provisioned MBS User Data Ingest session is scheduled to become active (see clause 4.5.5), or immediately if no schedule of active periods is provisioned, the MBSF establishes in the MBSTF all MBS Distribution Sessions comprising that MBS User Data Ingest Session as shown in Figure 5.3-2 below.
The MBS Application Provider creates an MBS User Data Ingest Session by invoking the Nmbsf_MBSUserDataIngestSession_Create service operation at reference point Nmb10 (or N33+Nmb5, if invoked via the NEF).
The MBS User Data Ingest Session optionally includes a schedule of start and end times referred to as active periods.
The MBS User Data Ingest Session comprises the details of one or more MBS Distribution Session(s), as defined in clause 4.5.6. Each such MBS Distribution Session fully specifies one of the distribution methods defined in clause 6 and may optionally nominate a TMGI to be used if one was pre-allocated in step 1 above.
Step 4.
The MBS Application Provider subscribes to status events from the MBSF relating to the MBS User Data Ingest Session just created by invoking Nmbsf_MBSUserDataIngestSession_StatusSubscribe service operation at reference point Nmb10 (or N33+Nmb5, if invoked via the NEF).
Step 5.
The MBSF may notify the status of each created MBS User Data Ingest Session to the MBS Application Provider by invoking the Nmbsf_MBSUserDataIngestSession_StatusNotify callback service operation at reference point Nmb10 (or N33+Nmb5, if invoked via the NEF).
For each such MBS Distribution Session:
Step 6.
If a TMGI was not nominated by the MBS Application Provider in step 1 above, the MBSF allocates one at this point for the MBS Distribution Session by invoking the Nmbsmf_TMGI_Allocate service operation on the MB-SMF at reference point Nmb1, as specified in clause 9.1.2.2 of TS 23.247.
Step 7.
The MBSF creates an MBS Session to reserve resources in the MBS System for the MBS Distribution Session by invoking the Nmbsmf_MBSSession_Create service operation on the MB-SMF at reference point Nmb1, as specified in clause 9.1.3.6 of TS 23.247). The TMGI reserved for the MBS Distribution Session in step 1 or step 6 above is provided as an input parameter. The MBSF determines the other input parameters as specified in clause 4.5.9.
Step 8.
The MBSF creates the MBS Distribution Session in the MBSTF by invoking the Nmbstf_MBSDistributionSession_Create service operation at reference point Nmb2. This is a mirror of the entity in the MBSF (see clause 4.5.6). In the case of the Packet Distribution Method, the response may include additional content ingest parameters chosen by the MBSTF for this MBS Distribution Session (see MBSTF ingest endpoint addresses in Table 4.5.6-3).
Step 9.
In the case of the Packet Distribution Method, the MBSF invokes the Nmbsf_MBSUserDataIngestSession_StatusNotify callback service operation at reference point Nmb10 (or Nmb5+N33, if invoked via the NEF) to inform the MBS Application Provider of the content ingest parameters that have been chosen for this MBS Distribution Session (see MBSTF ingest endpoint addresses in Table 4.5.6-3).
Step 10.
The MBSF subscribes to status events from the MBSTF relating to the MBS Distribution Session just created by invoking the Nmbstf_MBSDistributionSessionStatusSubscribe service operation at reference point Nmb2.
Step 11.
The MBSTF attempts to establish content ingest from the MBS Application Provider at reference point Nmb8 according to the ingest parameters and distribution method provisioned for the MBS Distribution Session in question (see Table 4.5.6-1).
On success, the state of the MBS Distribution Session in the MBSTF becomes ESTABLISHED; on failure, it remains INACTIVE (see step 2 in clause 4.6.1).
Step 12.
The MBSTF invokes the Nmbstf_MBSDistributionSession_StatusNotify callback service operation at reference point Nmb2 to inform the MBSF of the (un)successful establishment of content ingest.
On success, the state of the MBS Distribution Session in the MBSF becomes ESTABLISHED; on failure, it remains INACTIVE (see step 2 in clause 4.6.1).
Step 13.
The MBSF invokes the Nmbsf_MBSUserDataIngestSession_StatusNotify callback service operation at reference point Nmb10 (or Nmb5+N33, if invoked via the NEF) to inform the MBS Application Provider of the (un)successful establishment of content ingest for the MBS Distribution Session in the context of its parent MBS User Data Ingest Session.
Step 14.
If content ingest was established successfully in step 11 above, the MBSF compiles the metadata relating to this MBS Distribution Session into an MBS Distribution Session Announcement, as defined in clause 4.5.8.
