Step 1.
The NWDAF service consumer (NWDAF containing AnLF or NWDAF containing MTLF) subscribes/requests for a (set of) trained ML Model(s) associated with a/an (set of) Analytics ID(s) by invoking the Nnwdaf_MLModelProvision_Subscribe / Nnwdaf_MLModelInfo_Request service.
Step 2.
The NWDAF containing MTLF determines whether the set of ML Model(s) associated with a/an (set of) Analytics ID(s) should be retrieved from the ADRF.
When NWDAF containing MTLF authorizes the NF consumer to retrieve the ML Model(s) stored in the ADRF directly, steps 3 and 4 is skipped.
If NWDAF containing MTLF determines that the set of ML Model(s) corresponding Analytics ID(s) requested in step 1 needs to be retrieved from ADRF and the NF consumer is agnostic to where the ML model(s) is stored, then Steps 3 and 4 is performed.
Step 3.
The ADRF service consumer (NWDAF containing MTLF) requests for the ML Model stored in ADRF by invoking the Nadrf_MLModelManagement_RetrievalRequest Request (Storage Transaction Identifier or one or more unique ML Model identifier(s)) service operation.
Step 4.
The ADRF verifies the service consumer (NWDAF containing MTLF) as described in Annex X.10 of
TS 33.501. If verification is successful, the ADRF sends
Nadrf_MLModelManagement_RetrievalRequest Response (ML Model file address of Model file(s) stored in ADRF) service operation.
Step 5.
The NWDAF containing MTLF notifies/ response to the NWDAF service consumer with the tuple Analytics ID, one or more tuples of unique ML Model identifier and ML Model Information. The ML Model information may contain the ML Model file address or ADRF (Set) ID. The ADRF(Set) ID is included only when the NWDAF containing MTLF authorizes the NF consumer to retrieve the ML Model(s) stored in the ADRF in step 2. When ADRF (Set) ID is provided and the NWDAF containing MTLF authorizes the NF Service Consumer to retrieve all ML Models corresponding to a Storage Transaction ID, the Storage Transaction ID may be provided. In other cases, the NWDAF containing MTLF only provides ML Model identifier(s).
Step 6.
If in step 5, the NWDAF service consumer (NWDAF containing AnLF or NWDAF containing MTLF) received ADRF (Set) ID (where the ML Model(s) requested in step 1 is stored) and/or the ML Model provide indicator, then the NWDAF service consumer may invoke the Nadrf_MLModelManagement_RetrievalRequest (Storage Transaction Identifier or one or more unique ML Model identifier(s)) service operation to get the ML Model stored in ADRF.
Step 7.
The ADRF verifies the service consumer as described in Annex X.10 of
TS 33.501. If verification is successful, the ADRF sends
Nadrf_MLModelManagement_RetrievalRequest Response (ML Model identifier(s) and address(es) of Model file(s) stored in ADRF to the NWDAF service consumer.