Section: 4.2 High level common architecture 4.2.1 General
Content: The architectural differences between the domains (e.g. PS), services (e.g. MMS) and subsystems (e.g. the IMS) affect the way in which the charging functions are embedded within the different domains, services and subsystems. However, the functional requirements for charging are always the same across all domains, services and subsystems. This clause describes a common approach for the definition of the logical charging functions, which provides a ubiquitous logical charging architecture for all 3GPP network domains, subsystems and services that are relevant for charging standardisation. It should be noted that this common charging architecture provides only a common logical view and the actual domain / service / subsystem specific charging architecture depends on the domain / service / subsystem in question. The physical mapping of the common logical architecture onto each domain, subsystem or service is described in the respective middle tier TS, i.e. the TS 32.25[ None ] x, TS 32.26[ None ] xand TS 32.27[ None ] x number ranges. Figure 4.2.1.1 provides an overview of the logical ubiquitous charging architecture and the information flows for offline and online charging, in both referent points and service based interface variants, respectively further detailed in clause 4.2.2 and clause 4.2.3. The common architecture for Network Slice Charging is provided in clause 4.2.4 The common charging functions are detailed further for the reference points variant, in clauses 4.3.1 for offline charging, and clause 4.3.2 for online charging, and for the service based interface variant in clause 4.3.3 for converged online and offline charging. The reference points are further specified in clause 4.4. The service based interface is further specified in clause 4.2.3. Figure 4.2.1.1: Logical ubiquitous charging architecture and information flows