School of Specs 23.501v20.2.0

3GPP 23.501 v20.2.0 — the document's own text

4.3.3.2 Roaming architecture

Taught in 19. Living next to 4G (The 5G system architecture, in depth), 7. Roaming, other accesses, the edge and the outside (The 5G system architecture, overview).

Figure 4.3.3.2-1 represents the Roaming architecture with local breakout and Figure 4.3.3.2-2 represents the Roaming architecture with home-routed traffic for interworking between 5GC via non-3GPP access and EPC/E-UTRAN.

Figure 4.3.3.2-1: Local breakout roaming architecture for interworking between 5GC via non-3GPP access and EPC/E-UTRAN
Figure 4.3.3.2-1: Local breakout roaming architecture for interworking between 5GC via non-3GPP access and EPC/E-UTRAN

NOTE 1: There can be another UPF (not shown in the figure above) between the N3IWF/TNGF and the UPF + PGW-U, i.e. the UPF + PGW-U can support N9 towards the additional UPF, if needed.

NOTE 2: S9 interface from EPC is not required since no known deployment exists.

NOTE 3: N26 interface is not precluded, but it not shown in the figure because it is not required for the interworking between 5GC via non-3GPP access and EPC/E-UTRAN.

Figure 4.3.3.2-2: Home-routed roaming architecture for interworking between 5GC via non-3GPP access and EPC/E-UTRAN
Figure 4.3.3.2-2: Home-routed roaming architecture for interworking between 5GC via non-3GPP access and EPC/E-UTRAN

NOTE 4: N26 interface is not precluded, but it not shown in the figure because it is not required for the interworking between 5GC via non-3GPP access and EPC/E-UTRAN.