The telecom industry's shift toward large-scale next-generation network deployment is fundamentally changing the consumption paradigm for communication services. While billing systems (BSS) were previously designed to handle millions of human subscriptions, operators now face the challenge of billing billions of Machine-to-Machine (M2M) and Internet of Things (IoT) connections. This explosive growth, accompanied by a shift from daily batch cycles to sub-second events, requires a radical restructuring of architectural approaches to traffic processing, mediation, and monetization.
Why 5G Standalone and the M2M traffic explosion disrupt classic billing
According to the Ericsson Mobility Report (November 2025), over 90 service providers worldwide have already launched or are preparing to launch commercial 5G Standalone (SA) services. The 5G Core architecture, standardized by the 3GPP consortium, is built on service-oriented, cloud-native principles (Service-Based Architecture, SBA). This allows operators to dynamically allocate network slices for specific business needs.
At the same time, it is important to understand that 5G SA is not the only technology for IoT—legacy networks remain relevant for low-power devices. The main problem lies in the BSS domain. Traditional systems are designed for large transactions. In the IoT world, a device can generate micro-sessions every few seconds. Attempting to process such a stream using classic methods instantly overloads databases.
Architectural limitations of legacy BSS: why batch processing (CDR) no longer works
Historically, telecom operators relied on batch processing of Call Detail Records (CDR). Network equipment recorded session completion, generated a file, which then spent hours passing through a mediation chain to final billing. For IoT/M2M, this model creates several critical threats:
- Revenue leakage: If a device with abnormal consumption continues to generate traffic, the operator only learns about it after the batch processing cycle closes.
- Database locking: Attempting to write billions of small transactions directly into a monolithic relational DBMS causes deadlocks. According to architectural tests, up to 53.7% of attempts to process high-frequency IoT traffic through classic batch cycles lead to critical system slowdowns.
- Tight coupling: When the rating engine is integrated into a monolith, a surge in M2M activity paralyzes other BSS business functions.
Transitioning to event-driven architecture: TM Forum ODA principles in IoT monetization
A viable solution is to move away from batch processing in favor of an Event-Driven Architecture (EDA). The reference standard here is the Open Digital Architecture (ODA) developed by the TM Forum. ODA replaces monolithic BSS/OSS with a component-based architecture using open APIs.
It should be noted that TM Forum ODA is not a ready-made "plug-and-play" solution. It is a reference architecture that requires significant integration effort. In the context of IoT, it involves transitioning from batch CDR processing to real-time event streaming. The rating component subscribes to network events and processes them "on the fly," ensuring sub-second response times.
Decoupling and horizontal scaling: how to separate the rating engine from the monolith
To ensure BSS stability, it is necessary to decouple the rating engine. A modern module must meet several requirements:
- Stateless architecture: The rating engine should not maintain a constant connection to a heavy database during every transaction.
- Horizontal scaling: Rating components are deployed as dynamic microservices (e.g., in Kubernetes), allowing for independent scaling during activity spikes. Thanks to decoupling, the load on the main billing monolith can be reduced by 27.7%, freeing up resources for calculation operations.
- Asynchronous writing: The financial result is written asynchronously to the main accounting system, preventing delays.
Integrating real-time anti-fraud modules to protect automated devices
The processes of automatically connecting billions of M2M devices create serious vectors for abuse. According to the CFCA Global Fraud Loss Survey 2025, global losses from telecom fraud amounted to $41.82 billion, of which about $5.31 billion was attributed to subscription fraud.
To minimize risks, anti-fraud modules are integrated directly into the real-time event processing loop (inline mediation). If the system detects an anomaly, it instantly initiates a blocking command. Although real-time billing does not eliminate all types of fraud, it is a fundamental first line of defense in automated environments.
Evolutionary transition: modernizing BSS without stopping critical services
Completely replacing a BSS monolith is a long and risky process. The most rational approach is to move high-load mediation and rating functions to specialized platforms.
The technology alliance Intecracy Group—an alliance of independent companies linked by partner agreements and share exchanges—offers proven solutions for such tasks. In particular, the operator VoIP platform DooxSwitch contains integrated real-time billing and routing modules adapted for processing IoT/M2M provisioning alongside classic traffic.
For building custom integration layers and mediation systems, the UnityBase platform is used—a joint development of Intecracy Group companies (where InBase is a key, but not the only, developer). As a full-stack JavaScript low-code / model-driven framework, UnityBase allows for the rapid design of Domain metadata and the generation of REST API for integration with the 5G service-oriented core. Thanks to an asynchronous non-blocking HTTP server, solutions based on UnityBase can create a reliable buffer layer that accepts billions of events, rates them "on the fly," and securely transfers aggregated data to legacy systems.
| Comparison parameter | Legacy BSS (Batch-based) | Target architecture 2026 (Event-Driven ODA) |
|---|---|---|
| Data processing method | Batch (1-24 hour intervals via CDR) | Streaming (Event Streaming, sub-second response) |
| Rating module scaling | Vertical (expensive monolith capacity increase) | Horizontal (dynamic microservices in K8s) |
| Network integration | Tight coupling with signaling protocols | API-first via Service-Based Architecture (SBA) |
| Fraud protection | Post-factum analysis after batch cycle closure | Real-time blocking of anomalous sessions at the mediation level |
FAQ
How can real-time rating be integrated into an existing legacy BSS without a full core replacement?
An intermediate mediation and rating layer is implemented, which intercepts network events in real-time, rates them using fast In-Memory caches, and passes aggregated financial results to the legacy billing system, thereby offloading the main DBMS.
What is the role of TM Forum ODA in building modular billing systems for IoT?
TM Forum ODA provides a reference architecture and a set of open APIs that allow for the decoupling of monolithic BSS into independent components. This enables separate scaling of rating modules and reduces the risk of vendor lock-in.
How can fraud be prevented during the automatic provisioning of billions of M2M devices?
It is necessary to integrate anomaly detection modules directly into the event processing loop (inline mediation). Upon detecting atypical behavior, the system must instantly initiate session blocking at the network core level.