5.4.14.2 Setup of UE-Satellite-UE communication with IMS user plane components on-board satellites

The AMF reports the identifier of the satellite serving the UE to the SMF as part of the PDU Session establishment and update procedures as described in clauses 4.2.3, 4.3.2 and 4.3.3 of TS 23.502 [3].

NOTE 1: The AMF can determine that the UE is accessing gNB onboard a LEO or MEO satellite and can also determine the satellite identifier based on local configuration, e.g. Global RAN Node IDs associated with the LEO or MEO satellite.

Upon receiving a request from the P-CSCF for accessing network information report (e.g. as a result of the P-CSCF processing an IMS call setup), the PCF subscribes to Access Network Information report from the SMF for the IMS PDU Session, as described in clause 6.1.3 of TS 23.503 [45]. The Access Network Information report contains the identifier of the satellite serving the UE as reported by the AMF.

NOTE 2: How the serving satellite identifier is used by the IMS to determine whether the UE-Satellite-UE communication can be activated is specified in TS 23.228 [15].