3GPP 23.501 v20.2.0 — the document's own text
S.4.1 Control Plane Protocol Stacks to support N2 interface for MWAB node
Taught in 26. Relays, satellites, femtos and shared networks (The 5G system architecture, in depth).
Figure S.4.1-1 illustrates the Control Plane Protocol Stacks to support the N2 interface. A PDU session between MWAB-UE and MWAB-UPF is established as a backhaul link to support the overlayed N2 interface. The N2 interface terminates at MWAB-gNB and UE-AMF respectively, which includes NGAP and SCTP/IP layer protocols between them.