4 Architecture considerations

32.2783GPPCharging managementMonitoring event chargingRelease 17Telecommunication managementTS

4.1 High level monitoring event architecture

Figure 4.1.1 shows the overall architecture for Service Capability Exposure which enables the 3GPP network to securely expose its services and capabilities provided by 3GPP network interfaces to external 3rd party service provider applications, which includes Monitoring Event functionality, as described in TS 23.682 [243].

Figure 4.1.1: 3GPP Architecture for Service Capability Exposure

For roaming case, the Interworking SCEF (IWK-SCEF) is optionally deployed and located in the VPLMN, as described in figure 4.1.2.

Figure 4.1.2: 3GPP roaming Architecture for Service Capability Exposure

4.2 Monitoring Event offline charging architecture

As described in TS 32.240 [1], the CTF (an integrated component in each charging relevant NE) generates charging events and forwards them to the CDF. The CDF, in turn, generates CDRs which are then transferred to the CGF.
Finally, the CGF creates CDR files and forwards them to the BD.

For offline charging the following Monitoring Event Charging Nodes (MECN), functioning as the CTF, may generate accounting metrics sets for Monitoring Event CDRs:

– the MME, to record Monitoring Events;

– the SGSN, to record Monitoring Events;

– the IWK-SCEF, to record Monitoring Events.

If the MECN generating the charging information has an integrated CDF, then the MECN can produce CDRs. The CGF may also be integrated in the MECN, or it may exist as a physically separate entity.
If the CGF is external to the MECN/CDF, then the MECN/CDF forwards the CDRs to the CGF across the Ga interface. In this case, the relationship between MECN/CDF and CGF is m:1.
If the CGF is integrated in the MECN/CDF, then there is only an internal interface between the CDF and the CGF. In this case, the relationship between MECN/CDF and CGF is 1:1. An integrated CGF may support the Ga interface from other MECN/CDFs.

If the CDF is external to the MECN, the charging events are transferred from the MECN to the CDF via the Rf interface specified in TS 32.299 [50]. In this case, the relationship between MECN and CDF is m:1.

When an external CGF is used, this CGF may also be used by other, i.e. non-Monitoring Event, network elements, according to network design and operator decision. It should be noted that the CGF may also be an integrated component of the BD – in this case, the Bmn interface does not exist and is replaced by a proprietary solution internal to the BD.

Figure 4.2.1 depicts the architectural options described above.

Figure 4.2.1: Monitoring Event offline charging architecture

It is mandatory to support at least one of the Rf, Ga or Bmn interfaces from the MECN as described in the present document.

NOTE: Support of Monitoring Event charging is optional for MECN.

4.3 Monitoring Event online charging architecture

Not specified in the present document.