5.3.1 Basic principles

32.2753GPPCharging managementMultiMedia Telephony (MMTel) chargingRelease 17Telecommunication managementTS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

Online charging of MMTel services is done according to the general principles of Diameter Credit-Control Applications (Debit / Reserve Units Response) as specified in TS 32.299 [50].

The CTFs implementing the MMTel online charging functionality may apply:

– Immediate Event Charging (IEC) with Debit Units Request [Event] generated, or

– Event Charging with Unit Reservation (ECUR), or Session Charging with Unit Reservation (SCUR), both with Reserve Units Request [Initial or Termination] generated.

The circumstances on which IEC, ECUR or SCUR are applied, depend on the MMTel supplementary service and/or operator’s policy. Further details are specified in clause 5.3.2.