3GPP 23.501 v20.2.0 — the document's own text
5.34.10 Support for 5G LAN-type service
Taught in 26. Relays, satellites, femtos and shared networks (The 5G system architecture, in depth).
This clause defines how 5GS supports 5G LAN-type service as defined in clause 5.29 in the case of deployments topologies with specific SMF Service Areas.
The UE may be connected with the PSA via an I-UPF which is controlled by the I-SMF. In this case, traffic switching (e.g. UPF local traffic switching) is controlled by the SMF as described in clause 5.29.4 without any specific knowledge or involvement of the I-SMF to support the 5G LAN-type service.