SAP System Separation and Rebuilding for One Hungary

THE CHALLENGE  

The Future of Telecommunications: Introducing One Hungary

One Hungary is one of the key players in the Hungarian telecommunications market today. The company offers a broad portfolio of services for both residential customers and small to large enterprises. It was established on January 1, 2025, through the merger of several well-known and significant market entities, including Vodafone Hungary, DIGI’s mobile and fixed-line networks, Antenna Hungária with over 50 years of broadcasting experience, and Invitech’s modern data center and cloud services. With this merger, One combines the expertise of the past with the technological solutions of the future. 

The consolidation of multiple large-scale organizations required not only business alignment but also a robust IT foundation capable of supporting future innovation and operational efficiency across the entire enterprise landscape.

Turning Challenge into Opportunity: SAP System Separation and Rebuilding 

Following the acquisition of Vodafone Hungary, executing a comprehensive carve-out project became a strategic priority for One. The goal was to separate the Hungarian business unit’s data stored in Vodafone Group’s S4/HANA, BW, GRC, and ADS SAP systems, as well as in the OpenText system serving as the content server. Furthermore, it was necessary to select and implement a new operating environment. The project’s objective was to ensure a seamless migration and deployment of the SAP systems onto the new platform. 

This phase demanded exceptional precision, as regulatory compliance, data integrity, and business continuity had to be preserved throughout the entire transformation process.

Ensuring Accuracy in SAP data migration

A critical success factor was the execution of the SAP data migration, which required strict validation rules and multiple test cycles to ensure consistency between the source and target systems. By isolating and validating business-critical datasets early, the project team significantly reduced operational risk. This approach ensured that SAP data migration supported uninterrupted business operations from day one.

THE SOLUTION

After a large-scale tender process, One selected Amazon Web Services (AWS) as its new platform and TC2 was entrusted with building and operating the required infrastructure. 

Several significant challenges had to be addressed during implementation: extremely tight deadlines for establishing a complex, highly available system, constantly evolving business and technological requirements, and strict compliance with information security standards. Thanks to TC2’s professional experience, proven methodologies, and AWS’s advanced technologies and services, the project successfully met all expectations.  

The transition also aligned with a broader enterprise-level cloud migration strategy, enabling greater flexibility and faster innovation cycles while maintaining strict governance controls.

A Cloud-Driven Vision: The TC2 and AWS Solution 

At the start of the project, TC2 created a sandbox SAP environment for testing purposes, which enabled One to validate the data separated from the Vodafone Group’s SAP system. 

The final SAP environment was built as part of an enterprise-grade Landing Zone specifically designed for the One group, based on TC2’s LaiZy product. This infrastructure provides critical IT services, including central network services (VPN, AWS Network Firewall, routing), monitoring (CloudWatch, Prometheus, Grafana), backup (AWS Backup), logging (OpenSearch), and security and incident management (Security Hub, GuardDuty, Config, CloudTrail). The environment included centralized billing and cost-allocation solutions. 

This architecture laid the foundation for scalable operations and future extensions, while the integration of cloud managed services simplified long-term maintenance and monitoring.

The production and test SAP systems were built on a high-availability architecture, in close collaboration with the SAP Basis team, with automated failover capabilities within 5–10 minutes in the event of an outage. The system supports over 3,000 users and runs on more than 70 SAP-certified EC2 instances. Shared file systems are handled by Elastic File System (EFS), while AWS Transfer Family provides the necessary SFTP services for interfaces. 

Governance and Risk Control in SAP System Migration

A well-structured SAP system migration approach ensured that business processes, authorizations, and integrations were preserved throughout the transition. Detailed cutover planning and rollback scenarios allowed the team to execute the SAP system migration with minimal disruption and predictable outcomes.

To meet strict security requirements, all stored data is encrypted using customer-managed keys provided by One via AWS Key Management Service (KMS). In addition, full micro-segmentation was implemented using AWS Network Firewall and Security Groups, resulting in more than a thousand firewall rules. 

Special attention was also given to document and content continuity, ensuring that the OpenText system remained fully integrated and accessible within the new environment.

The infrastructure was entirely deployed using Infrastructure as Code (Terraform) and CI/CD processes, enabling fast, efficient, controlled, and secure provisioning. TC2 demonstrated exceptional flexibility throughout the project—quickly adapting to changing requirements, such as setting up temporary development environments that could be shut down after use, ensuring that resources incurred costs only during actual utilization. Similarly, scaling demands were addressed promptly—for example, when higher-performance servers or additional storage capacity were needed. 

Stability, Scalability, Security – The Keys to Success 

Thanks to TC2’s experience and expertise, the advantages of Infrastructure as Code, and AWS’s services and solutions, the infrastructure setup turned out to be the smoothest part of a project that otherwise presented numerous business challenges. The implementation of this highly complex SAP on AWS platform was completed with remarkable speed and efficiency. As a result, infrastructure development did not become a bottleneck during the nearly year-long project, allowing the customer to focus on its business processes. 

From a strategic perspective, the successful SAP merge of multiple legacy environments into a unified operational model demonstrates how technical excellence can directly support business transformation. This SAP merge approach provides a scalable blueprint for future enterprise integrations.