CDF vs CDR vs CTF-functional difference CDF,CDR,CTF in LTE
This page compares CDF vs CDR vs CTF and mentions functional difference between CDF, CDR and CTF in LTE.
LTE CDF | Charging Data Function

• CDF stands for Charging Data Function.
• It is responsible for creating or constructing CDRs (Charging Data Records).
• It creates CDRs based on received charging events.
• The charging events are received by CDF through reference point Rf.
• The CDRs generated by CDF are transferred to CGF (Charging Gateway Function) via Ga reference point immediately.
LTE CDR | Charging Data Record
• CDR stands for Charging Data Record.
• CDR is formatted collection of information about chargeable events for use in billing as well as accounting.
• Events can be time of call set-up, call duration, amount of data transferred etc.
• Separate CDR shall be generated for each party to be charged for parts of or all charges of a chargeable event.
This results into more than one CDR for long call duration and in the cases where more than one charged party is to be charged for.
• Charging event refers to set of charging information forwarded by CTF towards
towards the OCS (online charging) or CDF (offline charging).
• Each charging event matches exactly one chargeable event.
LTE CTF | Charging Trigger Function

• CTF stands for Charging Trigger Function.
• It is part of the service element.
• It is responsible for monitoring service usage and hence generating charging events based on the same.
Also refer Online and Offline charging➤ which uses CTF and CDF.
REFERENCE:
3GPP TS 32.240 version 6.2.0 Release 6