How China Telecom Achieved 100% Cloud Migration in Record Time

On November 8, 2020, China Telecom announced a bold cloud strategy: 100% of new systems would be built in the cloud and all existing IT systems would be migrated within three years. This marked the start of the carrier’s "cloud‑first" transformation.

By May 17, 2022, China Telecom announced that it had completed the cloud‑based reconstruction of its IT systems, becoming the first state‑owned enterprise to use a self‑developed database and achieve 100% cloud migration, setting a global record for the speed of such a transition.

01 “If the system crashes, I’ll resign with you!”

When the cloud migration task was first assigned, the team of six was responsible for moving roughly 3,000 systems, meaning each person would need to handle about 500 systems over three years.

02 “Crossing the river with a group army”

In 2017, China Telecom’s R&D team built the distributed TeleDB database and messaging system, launching the BSS3.0 pilot in Fujian. By 2018, the carrier planned to cloudify core billing and CRM systems serving billions of queries and calls.

Facing doubts about the stability of the self‑developed TeleDB, the team proceeded, creating a PaaS platform that would be the first of its kind among global telecom operators.

03 “Learn from the people of Saihanba, cross this hurdle”

During a resource shortage in 2021, the team drew inspiration from the Saihanba afforestation project, launching a "hundred‑day cloud sprint" and mobilizing over 200 partners and thousands of engineers. By November 2021, 85% of the target was achieved ahead of schedule.

In December 2021, the migration rate reached 95%, and the team completed the migration of 1,300 systems in 90 days, a feat dubbed the "Saihanba miracle".

04 “Seize the digital transformation ‘bull’s nose’”

By May 2022, all 3,000 systems were fully migrated, delivering a new digital foundation consisting of a unified cloud‑network platform, a self‑developed TeleDB database, and an integrated technology stack called "Yilong".

The carrier distilled its experience into a "five‑step, ten‑process" methodology covering planning, design, implementation, deployment, and operation, enabling other enterprises to achieve low‑cost, standardized, automated, and large‑scale cloud migration.

05 “Develop a new main business, find a second growth curve”

China Telecom’s cloud services became a major revenue driver, with Q1 2022 digital‑industry revenue reaching ¥29.4 billion, a 23.2% year‑over‑year increase. The success of the cloud migration also accelerated talent development, training over 20,000 employees and certifying thousands of partners.

Overall, the project reduced the total number of systems by 500, improved operational efficiency threefold, cut operating costs by 30%, and cultivated a new generation of cloud architects and engineers.