3GPP 23.501 v20.2.0 — the document's own text
8.2.1.2 5G-AN - AMF
Taught in 8. What actually travels on the wire (The 5G system architecture, in depth).

Legend:
- NG Application Protocol (NG-AP): Application Layer Protocol between the 5G-AN node and the AMF. NG-AP is defined in TS 38.413 [34].
- Stream Control Transmission Protocol (SCTP): This protocol guarantees delivery of signalling messages between AMF and 5G-AN node (N2). SCTP is defined in RFC 4960 [44].