Content for  TS 29.502  Word version:  18.5.0

The Update service operation shall be used for HR PDU sessions or for PDU sessions involving an I-SMF to:

• update an individual PDU session in the H-SMF or SMF and/or provide the H-SMF or SMF with information received by the V-SMF or I-SMF in N1 SM signalling from the UE;
• update a MA PDU session to indicate an additional access type, if the UE requests establishment of MA PDU session via the other access after the UE is registered to both 3GPPP access and non-3GPP access and the MA PDU session was successfully established on the first access (see clause 4.22.2.2 of TS 23.502);
• release a MA PDU session over a single access in the H-SMF or SMF;
• update an individual PDU session in the V-SMF or I-SMF and/or provide information necessary for the V-SMF or I-SMF to send N1 SM signalling to the UE.

It is invoked by the V-SMF or I-SMF in the following procedures:

• UE or network (e.g. V-SMF, I-SMF) requested PDU session modification (see clauses 4.3.3.3 and 4.23.5.3 of TS 23.502);
• UE or network (e.g. AMF, V-SMF, I-SMF) requested PDU session release (see clause 4.3.4.3 of TS 23.502);
• UE or network (e.g. AMF, V-SMF, I-SMF) initiated MA PDU session release over a single access (see clause 4.22 of TS 23.502);
• EPS to 5GS handover execution using N26 interface (see clause 4.11 of TS 23.502);
• Handover between 3GPP and untrusted or trusted non-3GPP access procedures (see clauses 4.9.2 and 4.9.3 of TS 23.502), without AMF change or with target AMF in same PLMN;
• All procedures requiring to provide the H-SMF or SMF with information received by the V-SMF or I-SMF in N1 SM signalling from the UE to the H-SMF or SMF;
• Secondary RAT Usage Data Reporting (see clause 4.21 of TS 23.502);
• UPF anchored Mobile Originated Data Transport in Control Plane CIoT 5GS Optimisation (see clause 4.24.1 of TS 23.502);
• Connection Resume in CM-IDLE with Suspend procedure (see clause 4.8.2.3 of TS 23.502);
• Reporting of satellite backhaul change to SMF (see clause 5.43.4 of TS 23.501);
• UE Triggered Service Request without I-SMF/V-SMF change/removal (see clause 4.23.4.2 of TS 23.502) or UE Triggered Service Request with I-SMF/V-SMF change or with I-SMF insertion (see clause 4.23.4.3 of TS 23.502);
• Remote UE Report during 5G ProSe Communication via 5G ProSe Layer-3 UE-to-Network Relay without N3IWF (see clause 6.5.1.1 of TS 23.304;
• Support of Network Slice Replacement (see clause 5.15.19 of TS 23.501).

It is invoked by the I-SMF in the following procedures:

• Addition of PDU Session Anchor and Branching Point or UL CL controlled by I-SMF (see clause 4.23.9.1 of TS 23.502);
• Removal of PDU Session Anchor and Branching Point or UL CL controlled by I-SMF (see clause 4.23.9.2 of TS 23.502);
• Change of PDU Session Anchor for IPv6 multi-homing or UL CL controlled by I-SMF (see clause 4.23.9.3 of TS 23.502);
• Sending by I-SMF of N4 notifications related with traffic usage reporting (see clause 5.34.6 of TS 23.501);
• Simultaneous change of Branching Point or UL CL and additional PSA controlled by I-SMF (see clause 4.23.9.4 of TS 23.502);
• Simultaneous change of Branching Points or UL CLs controlled by different I-SMFs (see clause 4.23.9.5 of TS 23.502).

It is invoked by the H-SMF or SMF in the following procedures:

• Network (e.g. H-SMF, SMF) requested PDU session modification (see clauses 4.3.3.3 and 4.23.5.3 of TS 23.502);
• Network (e.g. H-SMF, SMF) requested PDU session release (see clause 4.3.4.3 of TS 23.502);
• Network (e.g. H-SMF, SMF) initiated MA PDU session release over a single access (see clause 4.22 of TS 23.502);
• All procedures requiring to provide information necessary for the V-SMF or I-SMF to send N1 SM signalling to the UE;
• EPS Bearer ID allocation or revocation (see clauses 4.11.1.4.1 and 4.11.1.4.3 of TS 23.502);
• Secondary authorization/authentication by an DN-AAA server (see clause 4.3.2.3 of TS 23.502).

It is invoked by the SMF in the following procedures:

• Addition of PDU Session Anchor and Branching Point or UL CL controlled by I-SMF (see clause 4.23.9.1 of TS 23.502);
• Removal of PDU Session Anchor and Branching Point or UL CL controlled by I-SMF (see clause 4.23.9.2 of TS 23.502);
• Change of PDU Session Anchor for IPv6 multi-homing or UL CL controlled by I-SMF (see clause 4.23.9.3 of TS 23.502);
• Policy update procedures with an I-SMF (see clause 4.23.6.2 of TS 23.502);
• Simultaneous change of Branching Point or UL CL and additional PSA controlled by I-SMF (see clause 4.23.9.4 of TS 23.502);
• Simultaneous change of Branching Points or UL CLs controlled by different I-SMFs (see clause 4.23.9.5 of TS 23.502).