The GSM/UMTS core network charging architecture and principles are specified in this TS, which thus provides an umbrella for other charging management TSs.
A set of domain/subsystem/service specific TSs covers the domains (CS, PS, 5GS), subsystem (IMS) and service
(MMS, LCS, PoC, MBMS, SMS, MMTel etc.) levels, respectively, in the TS 32.25x, TS 32.26x and TS 32.27x TS
number ranges. These TSs describe the mapping of the common architecture specified in the present document onto the
specific domain/subsystem/service and the scenarios and information for online and offline charging that are specific to
the domain/subsystem/service. They are commonly referred to as the middle tier charging TSs.
A set of TSs in the TS 32.28x range covers common services, such as the Advice of Charge service.
A set of TSs in the TS 32.29x range covers common aspects, such as CDR parameter and syntax descriptions, online
and offline charging applications, and the charging interactions within the network (CDR transfer) as well as between
the network and the Billing Domain (CDR file transfer).