5.43.2 Edge Computing via UPF deployed on satellite

This clause only applies to the case where Edge Computing is deployed with UPF and Edge Computing services on-board the satellite. The UPF deployed on satellite can act as UL CL/BP/local PSA UPF or act as PSA UPF.

NOTE 1: In this Release, Edge Computing via UPF deployed on satellite only applies to GEO satellite backhaul.

To select the UPF deployed on satellite as PSA, the following enhancements apply:

• If the UE is accessing gNB with satellite backhaul and AMF is aware of the satellite backhaul category, the AMF sends the satellite backhaul category to the PCF. If GEO satellite backhaul category is indicated, the PCF may take it into account to generate or update the URSP rule as defined in clause 6.1.2.2 of TS 23.503 [45] to including an appropriate Route Selection Descriptor for services deployed on GEO satellite, which further enable PDU Session Establishment with PSA UPF on the satellite.

Based on GEO satellite ID provided by the AMF, the SMF performs PSA UPF selection or UL CL/BP/local PSA selection and insertion during the PDU Session Establishment procedure as described in clause 4.3.2 of TS 23.502 [3] or PDU Session Modification procedure as described in clause 4.3.3 of TS 23.502 [3] to select the UPF deployed on the GEO satellite if available, which includes:

• Based on configuration, the AMF may determine the GEO Satellite ID serving the UE and send it to the SMF. If GEO satellite ID changes, e.g. due to UE handover to an gNB using different GEO satellite as part of backhaul, the AMF may update the latest GEO Satellite ID to the SMF.

NOTE 2: It is assumed that AMF determines the GEO Satellite ID based on local configuration, e.g. based on Global RAN Node IDs associated with satellite backhaul.

• The SMF determines DNAI based on local configuration, DNN or S-NSSAI or both and the GEO Satellite ID received from AMF.

NOTE 3: It is assumed that one or more DNAI values are assigned for each GEO Satellite ID by the operator. SMF is locally configured with mapping relationship between DNAI and GEO Satellite ID.

• If the UE is allowed to access the service(s) according to the EAS Deployment Information as described in clause 6.2.3.4 of TS 23.548 [130], the SMF selects the PSA UPF or UL CL/BP/local PSA based on the DNAI corresponding to the GEO Satellite ID and other factors as described in clause 6.2.3.2 of TS 23.548 [130].

NOTE 4: EASDF may be deployed on satellite based on local configuration.