Over the past three months, Viettel High Tech, in coordination with Viettel Networks Corporation (Viettel Networks) and Viettel Telecom Corporation (Viettel Telecom), completed the migration of more than 100 million mobile subscribers and around 5,000 service packages from vOCS 3.0 to vOCS 4.0.
The migration was carried out directly on the live network without interrupting services. Users continued to use services normally while the backend system was replaced. Combined, the vOCS platforms currently serve more than 220 million subscribers in Viet Nam and 10 foreign markets.
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A representative from Viettel High Tech receives the award from the Organizing Panel of the Telecom Review Excellence Awards 2026 in Dubai. |
The Online Charging System (OCS) is a critical network system responsible for processing and charging calls, messages, data usage and promotional programs in real time. This is a technologically demanding field that was previously dominated by a small number of global technology corporations.
vOCS 4.0 can process more than 300,000 transactions per second, equivalent to over 1 billion transactions per hour, with latency of less than five milliseconds. Compared with its predecessor, the system reduces hardware investment costs by up to 50 percent, shortens deployment time by 30 percent and triples the speed of adding new features.
To achieve this performance, Viettel High Tech has mastered and developed the core technologies of vOCS 4.0, from the Cloud Native platform and Network Functions Virtualization Management and Orchestration (NFV-MANO) architecture to real-time charging, subscriber data and balance management technologies.
The system is specifically optimized for telecommunications networks, meeting stringent requirements for throughput, latency, scalability and high availability while serving more than 100 million subscribers.
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Engineers from Viettel High Tech, Viettel Networks and Viettel Telecom migrate Viettel’s mobile subscribers in Viet Nam from the vOCS 3.0 real-time charging system to vOCS 4.0. |
General Director of Viettel Networks Luu Manh Ha said that through practical deployment, the corporation highly valued vOCS 4.0 for its performance, stability, accuracy and scalability. The system has passed rigorous tests of real-time fault detection and recovery, enabling the network operator to maintain 24/7 service.
According to the official, vOCS 4.0 is in line with Viettel Networks’ technological transformation. The use of virtualized hardware allows resources to be shared flexibly, simplifying operations, accelerating the development of new features and generating significant cost savings. More importantly, mastering the charging system helps ensure digital sovereignty and operational flexibility without dependence on foreign technologies.
General Director of Viettel High Tech Nguyen Minh Quang said vOCS 4.0 supports 2G, 3G, 4G and 5G networks as well as fixed services on a single platform. Business units can quickly configure service packages, reducing the time needed to launch new products from days to hours. The system is ready to support domestic and international operators in exploiting the potential of 5G and digital services.
Viettel High Tech has officially introduced vOCS 4.0 to international operators, opening up opportunities for “Make in Viet Nam” technology to participate more deeply in the global telecommunications value chain.
About vOCS 4.0
Viettel began developing its charging system in 2012. In 2017, vOCS 3.0 replaced a foreign system serving 90 million subscribers in Viet Nam and overseas markets. Since 2020, Viettel High Tech has developed vOCS 4.0, which by 2026 has been scaled to serve more than 100 million subscribers.
The system is deployed at two data centers located 2,000km apart. If one center fails, the other automatically takes over and restores services within two minutes.
About the Telecom Review Excellence Awards
The annual Telecom Review Excellence Awards are organized by the Telecom Review Group. The 20th edition, held in 2026, brought together more than 600 technology industry leaders and was evaluated by an independent panel of experts.
The “Best Technology Deployment in Asia” category has previously honored ZTE, Mavenir and stc Group. Other categories have recognized global technology companies such as Huawei, Nokia and NEC.
Translated by Minh Anh