Description
The Converged Charging System (CCS) is a core network function defined by 3GPP for online charging. It represents a fundamental architectural evolution from legacy, service-specific charging systems to a unified, real-time charging platform. The CCS integrates the functions of the Online Charging System (OCS) and the Charging Data Function (CDF) for online charging, providing a single point of interaction for network elements requiring real-time credit control. It operates based on the Diameter Ro and Gy reference points, interfacing with Policy and Charging Rules Functions (PCRF/PCRF), application servers, and network gateways.
Architecturally, the CCS is built around the concept of a Charging Function (CHF), which is its central logical entity. The CHF communicates with network functions via standardized service-based interfaces (e.g., Nchf) in 5G Core networks. It processes charging events in real-time, applying tariff logic, deducting funds from user accounts, and granting or denying service units based on available credit. Key internal components include the Account Balance Management Function (ABMF) for managing subscriber balances and the Rating Function (RF) for determining the monetary cost of service usage events.
Its role in the network is pivotal for monetization and service control. The CCS authorizes network resource usage in real-time before or during a service delivery, enabling prepaid, on-demand, and sponsored data services. It generates standardized Charging Data Records (CDRs) for billing and settlement. By decoupling charging logic from specific network services, the CCS allows operators to rapidly introduce and tariff new services—like 5G network slices, IoT data plans, or edge computing services—without deploying separate charging infrastructure for each.
Purpose & Motivation
The CCS was created to address the limitations of fragmented, legacy charging systems where each service type (circuit-switched voice, packet data, SMS, IMS) had its own dedicated charging platform. This siloed approach led to operational complexity, high costs, and an inability to offer unified, cross-service charging plans (e.g., shared data buckets for voice and data). The proliferation of new IP-based services and the shift towards all-IP networks (IMS) demanded a more agile and consolidated charging architecture.
The primary problem it solves is the convergence of real-time charging across all access technologies (2G/3G/4G/5G, fixed) and all service types onto a single, standardized platform. This convergence enables operators to implement innovative, personalized pricing models and launch services faster. It also provides a future-proof foundation for charging in 5G Standalone networks, where network slicing and service-based architecture require a flexible, software-defined charging function that can interact dynamically with other network functions via APIs.
Historically, its introduction in 3GPP Release 11 marked a significant step towards the full realization of the Policy and Charging Control (PCC) architecture, providing a unified online charging entity. It addressed the need for a single source of truth for subscriber credit and balance management, improving revenue assurance and reducing the risk of credit fraud across disparate service domains.
Classification
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (262 CRs across 6 releases). Complements the general historical overview above with the evidence-based evolution of this function.
Studied in Rel-11, normative work from Rel-15.
In Release 15, the Converged Charging System (CCS) was introduced as a new network entity for IMS-based Peer-to-Peer Content Distribution Services, responsible for caching and distributing content. The release defined new interfaces for this CCS function, including the PP_s1 and PP_m1 interfaces for communication with UEs, and the Tc interface for control by a Tracker AS. Furthermore, procedures such as the CCS Joining Procedure were specified to enable the CCS to dynamically join a P2P swarm and retrieve content from a Content Source Server (CSS).
- Introduce the Northbound API charging TS 32.240CR0394
- Introduction of 5G in charging architecture TS 32.240CR0396
- Introduction of 5G converged charging TS 32.240CR0397
- Introduction of 5G in charging mechanisms TS 32.240CR0399
- Introduce the 5G charging in clause 3 TS 32.240CR0401
- Charging mode clarifications in Converged Charging System TS 32.240CR0402
+ 13 more changes
In Release 16, the key new feature for the Converged Charging System (CCS) was the introduction of comprehensive offline-only charging capabilities. This included the definition of offline charging service procedures, the generation of offline-only Charging Data Records (CDRs), and the specification of detailed message formats for this charging mode. Furthermore, the release added specific offline charging triggers and information for various network functions, including the SMF, QoS flow-based charging, and SSC modes.
- Introduction of AMF in charging architecture TS 32.240CR0409
- Add offline only charging TS 32.255CR0035
- Add offline only charging for SMF TS 32.255CR0036
- Add offline only charging CDR generation TS 32.255CR0038
- Add description of charging information for offline only charging TS 32.255CR0039
- Add offline only charging for flow based charging TS 32.255CR0040
+ 43 more changes
In Release 17, the Converged Charging System (CCS) was enhanced to support new 5G service capabilities, including specific charging architectures and requirements for 5G LAN services, Edge Computing, and Ultra-Reliable Low-Latency Communication (URLLC). The release introduced detailed charging principles, quota management, and usage reporting procedures for these services, such as for URLLC charging. It also expanded the logical charging architecture to include entities like the PGW and the 5G DDNMF.
- Add PGW in logical ubiquitous charging architecture- service based interface TS 32.240CR0413
- Introduction of 5G DDNMF in charging architecture for 5GS TS 32.240CR0429
- Addition of the 5G LAN service charging TS 32.240CR0434
- Charging architecture for Local Breakout TS 32.240CR0439
- Addition of the architecture for 5G LAN charging TS 32.240CR0442
- Enhance charging architecture for Edge Computing TS 32.240CR0443
+ 61 more changes
In Release 18, the Converged Charging System (CCS) was enhanced with new charging support for 5G Media Streaming (5MBS) services, including specific principles, procedures, and architectural elements. The release also introduced slice-aware charging for roaming partners and added charging support for Time-Sensitive Networking (TSN) services. Furthermore, new charging principles were defined for Standalone Non-Public Networks (SNPN) and for 5G data connectivity via satellite access.
- Adding New Consumer for MMS in Charging Architecture TS 32.240CR0446
- Slice-aware charging for Roaming partners TS 32.240CR0467
- Add MB-SMF in charging architecture for 5GS TS 32.240CR0470
- Add charging support for TSN service TS 32.240CR0473
- Add annex for B2B charging TS 32.240CR0474
- Update B2B charging principles TS 32.240CR0475
+ 80 more changes
In Release 19, the Converged Charging System (CCS) was extended with new charging principles and architectural support for emerging services. Key additions include specific charging support for AIoT (AI and IoT) services, integration of the CAPIF framework for API-based service charging, and new charging models for Unmanned Aircraft Systems (UAS). The release also introduced charging principles for satellite roaming, disaster roaming, and MVNOs providing satellite service, alongside enhancements for volume-based charging on IMS data channels.
- Introduction of GMLC in charging architecture for 5GS TS 32.240CR0491
- Rel-19 CR 32.240 Add charging support to AIoT service TS 32.240CR0510
- Rel-19 CR 32.240 CAPIF Logical Charging Architecture TS 32.240CR0511
- Rel-19 CR 32.240 CAPIF Service Charging TS 32.240CR0512
- Add charging principles for UAS TS 32.240CR0517
- Add MVNO charging which provides satellite service TS 32.240CR0518
+ 31 more changes
In Release 20, the Converged Charging System (CCS) was enhanced to support new Peer-to-Peer Content Distribution Services (P2P CDS) over IMS, introducing the CCS network entity that caches content and interacts with a Tracker AS via the Tc interface. Specific updates included defining new information elements for charging aspects of multi-modality services and for the charging impacts from enhanced QoS handling. Additionally, corrections were made to descriptions for QoS flow-based charging and to PDU Session ID handling for V-SMF charging in EPS-5GS interworking scenarios.
- Add informatin elements to support charging aspects of multi-modality service TS 32.255CR0606
- Rel-20 TS 32.255 Add information elements to address charging impacts from enhanced QoS handling in XRM TS 32.255CR0616
- Rel-20 CR 32.255 Correct some descriptions on QoS flow Based Charging TS 32.255CR0619
- Rel-20 CR 32.255 Correction on PDU Session ID Handling for V-SMF Charging in EPS–5GS Interworking TS 32.255CR0622
Explore further
Broader topics and technologies where CCS plays a role.
Defining Specifications
3GPP specifications that define or reference CCS, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 23.844 vc00 | IMS P2P Content Distribution Services Study | Rel-12 |
| TS 25.709 vf00 | Simplified HS-SCCH for UMTS Study | Rel-15 |
| TS 25.766 vd10 | Network-Assisted Interference Cancellation for UMTS | Rel-13 |
| TS 28.203 vi10 | Charging management | Rel-18 |
| TR 28.840 vi10 | Technical Report | Rel-18 |
| TR 28.843 vi10 | Technical Report on Charging Aspects for Vertical Scenarios | Rel-18 |
| TS 29.594 vj20 | 5G Spending Limit Control Service Stage 3 | Rel-19 |
| TS 32.240 vj40 | Charging Management Architecture & Principles | Rel-19 |
| TS 32.255 vk10 | Telecom Management; Charging for 5G Data Connectivity | Rel-20 |
| TS 32.256 vj40 | 5G Connection & Mobility Charging Spec | Rel-19 |
| TS 32.279 vj00 | 5G MBS Session Converged Charging | Rel-19 |
| TS 32.290 vj50 | 5G Charging for Service Based Interface | Rel-19 |
| TS 38.306 vj00 | NR UE Radio Access Capability Parameters | Rel-19 |