Description
A Charging Data Record (CDR) is a formatted data set produced by Charging Trigger Functions (CTFs) within network elements like the SGSN, GGSN, or P-GW. It documents a specific service usage event, such as a voice call, SMS, or data session. The creation is triggered by predefined charging events (e.g., session start, stop, or volume threshold). The CDR contains numerous fields including a unique record identifier, serving network identity, subscriber identifiers (e.g., IMSI, MSISDN), service data (start/stop time, data volume, QoS), and charging characteristics. Once generated, the CTF forwards the CDR via the Ga interface to a Charging Data Function (CDF) for further processing. The CDF validates, merges related partial records, and formats the CDR before transferring it to a billing domain system. Its role is critical for Offline Charging (OFC), where billing occurs after service consumption. The architecture ensures a clear separation between the network elements generating usage and the centralized charging system, providing an auditable trail for revenue assurance. CDRs are also used for statistical analysis, fraud detection, and network planning beyond pure billing.
Purpose & Motivation
The CDR exists to provide a standardized, reliable mechanism for service usage metering and billing in telecommunications networks. Prior to its formalization, billing systems were often proprietary and tightly coupled with switches, making multi-vendor interoperability and complex tariff plans difficult. The CDR, as defined in 3GPP standards, solves this by creating an abstract, technology-agnostic record of consumption that can be generated by any compliant network function. This separation allows operators to introduce new services and network elements without overhauling their core billing infrastructure. Historically, its introduction in R99 was pivotal for the packet-switched domain of GSM/GPRS, enabling the billing of data services which have variable parameters unlike traditional voice calls. It addresses the problem of correlating usage from multiple network nodes (e.g., roaming scenarios) into a single, billable event for the subscriber.
What changed in its specifications
The latest release-to-release comparison of specifications that define CDR. Each summary describes the whole specification, not only this term.
Rel-18 brings only minor changes to TS 21.905: 0 clauses changed, with no change attributed to a release feature.
Full comparison in TR 21.905 →Rel-19 brings only minor changes to TS 22.115: 1 clause changed, with no change attributed to a release feature.
Full comparison in TS 22.115 →Release Timeline
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (73 CRs across 6 releases). Complements the general historical overview above with the evidence-based evolution of this function.
- Add CDR parameter for WLAN-based ProSe direct discovery TS 32.298CR0654
- Introduction of CHF-CDR TS 32.298CR0667
- Addition of DataVolumeOctets in generic CDR part TS 32.298CR0668
- Addition of SMS Charging to CHF CDR TS 32.298CR0680
- Addition of SMS info to CHF CDR TS 32.298CR0682
- Add new 5G TS in CDR header description TS 32.297CR0031
+ 5 more changes
- Adding I-SMF related SMFTrigger in CHF CDR TS 32.298CR0780
- Addition of CHF CDR for exposure function northbound API TS 32.298CR0786
- Correction of BGCF CDR description TS 32.260CR0397
- Correction of BGCF CDR description TS 32.298CR0723
- Incomplete indicator missing in CDR TS 32.298CR0795
- Correcting backwards compatibility on CHF CDR TS 32.298CR0817
+ 14 more changes
- Updating CDR handling for converged charging TS 32.260CR0417
- Introduction of CDR generation and handling for 5G ProSe converged charging TS 32.277CR0042
- Add CDR file format for Edge Computing charging TS 32.297CR0039
- CHF CDR enhancements to support of GERAN and UTRAN TS 32.298CR0875
- Add charging information related to CIoT in CHF CDR TS 32.298CR0890
- Introduce 5G ProSe charging information to CHF CDR TS 32.298CR0901
+ 9 more changes
- Rel-18 CR 32.298 Add TSN specific charging information to CDR TS 32.298CR0978
- Add the support of 5G satellite access charging to CHF CDR TS 32.298CR0986
- Add 5G satellite backhaul charging to CHF CDR TS 32.298CR0987
- Rel-18 CR 32.260 Addition of invocation timestamp in CDR TS 32.260CR0435
- Rel-18 CR 32.298 Addition of invocation timestamp in CHF CDR TS 32.298CR0960
- Rel-18 CR 32.270 Clarification on MMS CHF CDR TS 32.270CR0037
+ 6 more changes
- Add CDR generation and handling for converged charging of Ranging and Sidelink Positioning TS 32.271CR0023
- Extend basic priciples, CDR generation and handling for 5G LCS converged charging TS 32.271CR0030
- Add charging information to CDR for Ranging and Sidelink Positioning TS 32.298CR1022
- Add layer 3 multi-hop ProSe UE-to-Network relay communication related CDR parameters TS 32.298CR1033
- Extend CHF-CDR for 5G LCS converged charging TS 32.298CR1034
- Rel-19 CR TS 32.298 Add charging information to CDR for 5GS LCS TS 32.298CR1038
+ 4 more changes
- Rel-20 CR TS 32.298 Add CDR parameters to support charging aspects of QoS report enhancement TS 32.298CR1070
- Rel-20 CR TS 32.298 Add CDR parameters to support charging aspects of multi-modality service TS 32.298CR1071
- Add CDR parameters of host PLMN ID under INS case TS 32.298CR1079
- Rel-20 CR TS 32.260 Correction on the description of CHF CDR trigger TS 32.260CR0463
- Rel-20 CR TS 32.298 Correction on the description of CauseForRecClosing field in CHF CDR TS 32.298CR1075
Defining Specifications
3GPP specifications that define or reference CDR, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TR 21.905 vj20 | 3GPP Terminology and Definitions | Rel-19 read |
| TS 22.115 vj11 | 3GPP Charging and Billing Service Aspects | Rel-19 read |
| TS 22.121 v531 | Virtual Home Environment Service Requirements | Rel-5 read |
| TS 22.234 vd10 | 3GPP-WLAN Interworking Index Specification | Rel-13 read |
| TR 22.950 vj00 | Feasibility Study on Priority Service | Rel-19 read |
| TS 22.976 | 3GPP TS 22.976 | R99 read |
| TS 23.039 v500 | SMSC to SME Interface Protocols | Rel-5 read |
| TS 23.060 vj00 | GPRS Stage 2 Service Description | Rel-19 read |
| TS 23.125 v700 | Flow Based Charging Architecture | Rel-7 read |
| TS 23.140 v690 | MMS Stage 2 & 3 Specification | Rel-6 read |
| TS 23.167 vk10 | IMS Emergency Services | Rel-20 read |
| TS 23.218 vj00 | IMS Call Model Specification | Rel-19 read |
| TS 23.222 vk10 | Common API Framework (CAPIF) | Rel-20 read |
| TS 23.228 vk10 | IP Multimedia Core Network Subsystem | Rel-20 read |
| TS 23.682 vj30 | Architecture for MTC and SCEF Enhancements | Rel-19 read |
| TS 23.815 v500 | IMS Charging Implications | Rel-5 read |
| TS 23.851 v610 | Network Sharing Architecture for 3G Systems | Rel-6 read |
| TR 23.923 v300 | Mobile IP+ Feasibility Study for UMTS/GPRS | R99 read |
| TS 24.229 vk10 | IMS SIP/SDP Call Control Protocol | Rel-20 read |
| TS 24.802 vc10 | IMS II-NNI Traversal Scenario Determination Study | Rel-12 read |
| TS 26.891 vg00 | Media Distribution Services in 5G System | Rel-16 read |
| TS 28.203 vi10 | Charging management | Rel-18 read |
| TS 28.204 vi11 | Charging management | Rel-18 read |
| TR 28.816 vh00 | Charging for 5G Cellular IoT | Rel-17 read |
| TR 28.843 vi10 | Technical Report on Charging Aspects for Vertical Scenarios | Rel-18 read |
| TS 28.849 vj10 | CAPIF Phase2 Charging Study | Rel-19 read |
| TS 28.891 vk00 | CAPIF Converged Charging Study | Rel-20 read |
| TS 28.893 vk00 | ISAC Charging Study | Rel-20 read |
| TS 29.333 vj00 | MRFC-MRFP Mp Interface Protocol | Rel-19 read |
| TS 29.421 v810 | IMS Interworking with External IP Networks | Rel-8 read |
| TS 32.240 vk10 | 3GPP Charging Architecture and Principles | Rel-20 read |
| TS 32.250 vj00 | Circuit Switched Offline Charging | Rel-19 read |
| TS 32.251 vj00 | PS Domain Charging Management | Rel-19 read |
| TS 32.252 vc00 | 3GPP WLAN Interworking Charging | Rel-12 read |
| TS 32.260 vk10 | IMS Charging Management | Rel-20 read |
| TS 32.270 vj00 | MMS Charging Management Specification | Rel-19 read |
| TS 32.271 vj20 | 3GPP LCS Charging Management Spec | Rel-19 read |
| TS 32.272 vj00 | Charging for Push-to-Talk over Cellular (PoC) | Rel-19 read |
| TS 32.273 vj00 | MBMS Charging Management | Rel-19 read |
| TS 32.277 vj20 | Charging Management for Proximity Services (ProSe) | Rel-19 read |
| TS 32.278 vj00 | Monitoring Events Offline Charging Specification | Rel-19 read |
| TS 32.295 vj00 | 3GPP Charging: CDR Transfer via GTP' Protocol | Rel-19 read |
| TS 32.296 vj00 | Online Charging System (OCS) Architecture | Rel-19 read |
| TS 32.297 vj00 | Charging Data Record File Transfer | Rel-19 read |
| TS 32.298 vk10 | Charging Data Record Specification | Rel-20 read |
| TS 32.299 vj00 | Diameter Charging Applications for 3GPP | Rel-19 read |
| TS 32.808 v800 | Common Profile Storage Framework for User Data | Rel-8 read |
| TS 32.825 va00 | Study on Rc Reference Point for ABMF | Rel-10 read |
| TR 32.846 vh00 | Charging for ProSe in 5GS | Rel-17 read |
| TS 32.850 ve00 | IMS Charging Correlation Methods Study | Rel-14 read |
| TS 32.869 vf00 | Diameter Overload Control for Charging Interfaces | Rel-15 read |
| TS 33.849 ve00 | 3GPP Privacy Principles and Guidelines | Rel-14 read |