Section: E.2.1 High level common architecture
Content: The overall logical charging architecture is depicted below. The Rf and Ro reference points are applicable to GPRS, EPC or IMS NEs only, whereas the Nchf interface is applicable to 5GC NFs only. Figure E.2.1.1: High level overall charging architecture and information flows When the target charging system (i.e. 5G CCS or EPC OCS/OFCS) needs to support termination of a reference point or interface from the opposite type of core network (i.e. Ro/Rf or Nchf) implementations will need to include interworking between the HTTP used by SBI and the Diameter protocol.