23.2033GPPPolicy and charging control architectureRelease 17TS
The Offline Charging System is specified in TS 32.240 .
There may be several OFCSs in a PLMN. The default OFCS addresses (i.e. the primary address and secondary address) shall be locally pre-configured within the PCEF and TDF. OFCS addresses may also be passed once per IP‑CAN session or TDF session from the PCRF to the PCEF or TDF. The addresses provided by the PCRF shall have a higher priority than the pre-configured ones.