By 2026, implementing the Open Digital Architecture (ODA) from TM Forum has become a critical requirement for telecom operators aiming to compete in the cloud-native services segment. Legacy monolithic BSS/OSS systems, which have accumulated "spaghetti code" of business logic over decades, are increasingly difficult to maintain, and replacing them using traditional methods carries unacceptable risks to network stability.
Why 2026 is the deadline for moving away from monoliths
The evolution of network cores to service-oriented architectures, in accordance with 3GPP standards, requires similar flexibility from BSS/OSS support. The use of legacy protocols (SS7/Diameter) creates persistent vulnerabilities, as confirmed by the ENISA Threat Landscape 2025 report. At the same time, the growth of financial losses from telecom fraud, estimated at approximately $41.82 billion in 2025 according to the CFCA Global Fraud Loss Survey 2025, makes modernization not only a technical but also a financial priority.
The "all or nothing" trap and how to avoid it
Attempts to completely replace a monolith often lead to cascading failures. The "Strangler Fig" strategy allows for the gradual replacement of functionality. Iterative migration involves extracting a portion of the core functionality at each stage, ensuring stability during the transition period. Using an API-first approach, according to industry data, can significantly increase the efficiency of integrating new services compared to monolithic solutions.
UnityBase as a tool for modular architecture
The UnityBase platform, developed by companies within the Intecracy Group alliance—an alliance of independent companies linked by partner agreements and share exchanges—serves as an integration layer for BSS/OSS modernization. It provides centralization of domain metadata, allowing business rules to be managed independently of the hard-coded logic of legacy systems. The platform supports both cloud and on-premises deployment, ensuring RBAC/RLS access control and auditing required for mission-critical systems. Please note that for projects with high loads or increased security requirements, official documentation recommends the Enterprise or Defence editions of the platform.
Algorithm for iterative migration to ODA
- Audit the domain model and select an isolated business process.
- Create an API proxy to communicate with the legacy core and maintain data integrity.
- Deploy a new microservice based on UnityBase using centralized metadata.
- Validate the stability of the new module during parallel execution.
- Gradually decommission legacy code.
Risk management during migration
The transition to ODA is a complex process that requires deep architectural planning. Extracting client data via REST API allows for decoupling the modern interface from the backend, minimizing risks for the end user. An evolutionary approach allows for the transformation of a monolith not through radical replacement, but through controlled integration and metadata management.
FAQ
How to ensure data integrity in a hybrid environment (legacy + cloud-native)?
Using an API proxy and a centralized domain metamodel allows for data synchronization between new components and the legacy core, ensuring transactional integrity throughout the migration process.
Which business processes are safest to move to microservices first?
It is recommended to start with functionality that has minimal critical dependencies on the core, such as individual reporting services, client portals, or auxiliary billing modules.
How does metadata centralization help accelerate time-to-market?
The centralized metamodel in UnityBase automates the generation of APIs and access rules, which significantly reduces the amount of repetitive code when deploying new services.