Section: 5.5.3.9 Charging principles for 5G Roaming architecture with local breakout
Content: The 5G System roaming architecture with local breakout is specified in TS 23.501[ System architecture for the 5G System (5GS) ]  [215]. The breakout point for both the control plane signalling and user plane traffic is in the VPLMN, i.e. the vSMF and vUPF respectively. The VPLMN charging mechanism collects charging information related to the 5G data connectivity usage for each UE detected as in-bound roamer. The information collected include details of the services used by the visiting subscriber and it is conveyed to both the CHF in VPLMN and to the CHF in the HPLMN. The CHF in the VPLMN uses the collected charging information for wholesale charging including service aware towards the HPLMN The CHF in the HPLMN uses the collected charging information for retail charging towards the home subscriber while roaming. Charging for Roaming with Local Breakout is covered by the 5G data connectivity domain converged charging architecture specified in TS 32.255[ Telecommunication management; Charging management; 5G data connectivity domain charging; Stage 2 ]  [15], using the SMF embedding the CTF.