3GPP 23.501 v20.2.0 — the document's own text
5.20a Data Collection from an AF
Taught in 20. Computing close by, and opening the door (The 5G system architecture, in depth).
An NF that needs to collect data from an AF may subscribe/unsubscribe to notifications regarding data collected from an AF, either directly from the AF or via NEF.
The data collected from an AF is used as input for analytics by the NWDAF.
The details for the data collected from an AF as well as interactions between NEF, AF and NWDAF are described in TS 23.288 [86].