Section: 5.2.3 Charging data transfer in converged charging
Content: In converged charging, charging events mirroring the resource usage request of the user are transferred from the CTF or CEF to the CHF via the Nchf service-based interface. - The CTF determines whether to use Event based charging (IEC and PEC) or Session based charging (SCUR and ECUR). - The CEF determines the type of Event based charging (IEC and PEC) to use. The charging data transfer for the converged online and offline charging is the converged operation of the online and offline charging specified in the clause 5.2.1 and 5.2.2. Details on the protocol application for the Nchf interface, including the message types and the domain / subsystem /service content of the messages, can be found in TS 32.290[ Telecommunication management; Charging management; 5G system; Services, operations and procedures of charging using Service Based Interface (SBI) ]  [57] and TS 32.291[ Telecommunication management; Charging management; 5G system, charging service; Stage 3 ]  [58].