China Telecom has used the TM Forum Open Digital Architecture and Open APIs to migrate all its operational and business support systems (OSS/BSS) to the cloud, 20% of which are core systems that are now fully cloud-native. The capabilities have been delivered to various customers’ digital transformation projects.


opEX savings

CNY600 million

($88.7 million) through improved resource utilization

Improvement in R&D


and operational efficiency

Increase in related cloud service revenue

CNY470 million

($69.4 million)

Energy costs down by


Shao Guanglu
General Manager

“As the world’s biggest cloud service operator in the telecom field, China Telecom has successfully migrated its all IT systems to the cloud using the in-house developed Digital Enablement Platform named Yi Long. By leveraging cloud computing, China Telecom will collaborate with ecosystem partners to embrace future opportunities and empower our customers to achieve success in digital transformation.”

China Telecom is one of China’s largest telecom operators, serving more than 1 billion subscribers throughout the country’s 31 mainland provinces. The company formed its cloud network operation division in 2020 and started a corporate-wide digital transformation. By adopting a cloud-native architecture for its BSS, the new division oversees the migration of all 2,800 of its OSS/BSS to the cloud.

The company has been relying heavily on the TM Forum ODA and Open APIs throughout its digital transformation. An early adopter of the standards, China Telecom has signed both manifestos, committing to the design principles and essential standards required for a plug-and-play architecture. China Telecom is collaborating with supplier Whale Cloud to leverage the ODA, Open APIs and governance assets. So far, Whale Cloud has certified 35 Open APIs.

China Telecom’s primary goals have been to figure out how to use cloud-native technologies and digital platforms to move systems to the cloud on a massive scale, and to reduce the technical debt accumulated in its legacy architecture in a controlled way. By doing this, the company aims to achieve zero-touch and intelligent operations.

As the first step in this part of its digital transformation, China Telecom used a 'Five-Phase-Ten-Step' governance methodology based on TM Forum’s Transformation Project Framework to determine whether systems could be refactored to become cloud-native. The company used this approach to categorize systems into three groups: L3, L2, and L1.

L3 systems are truly cloud-native, while L2 systems are fairly easy to refactor and move to a platform-as-a-service (PaaS)-based model. L1 systems, on the other hand, are legacy systems that are difficult to refactor, so they are “wrapped” in Open APIs and use infrastructure-as-a-service (IaaS) to become cloud-based. Today 19% of China Telecom’s systems are classified as L3, or fully cloud-native. Close to half (47%) are L2, and 33% are L1.

Today, China Telecom has a centralized, geographically distributed Digital Enablement Platform connecting 143 data centers across the country. They are hosting more than 20,000 PaaS middleware instances and more than 19,000 source-code repositories.

The company has achieved:

  • Resilient and reliable IaaS and PaaS that can be accessed through self-service portals, with provisioning happening in minutes
  • End-to-end DevOps processes for all IT systems to fulfill agile iteration, deployment and delivery of the cloud-native model
  • Automatic collection and generation of a unified configuration management database (CMDB) for end-to-end monitoring of cloud operations to realize data-driven and AI-enabled operations and maintenance
  • Central governance of all the Open APIs used throughout the network

The results of China Telecom’s cloud transformation are impressive. By replacing its waterfall approach to OSS/BSS with Agile and DevOps practices including continuous integration and continuous delivery (CI/CD), the company is realizing opEX savings of nearly $90 million, plus improved efficiency, lower energy consumption and faster time to market. In addition, the service delivery period has been shortened from months to days, and fault-finding now happens in minutes rather than hours.

China Telecom is also passing along the capabilities to customers, providing enterprises with a converged cloud-network digital solution that goes beyond traditional communications services, while consumers receive faster monthly billing and new app-based services. The Yi Long Platform also supports more than 30 vertical projects with converged application, cloud, and network services for government agencies and enterprise customers. For example, China Telecom has delivered digital platform projects for a major heavy industry corporation and an intelligent industrial park in the Anhui Province.

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