Retrospectively entered on 24 September 2026. Timeline date reflects the publication date of the underlying research.

What happened

A paper published in npj Quantum Information on 8 August 2025 describes the China Quantum Communication Network (CN-QCN), reporting approximately 10,103 kilometres of fibre backbone, 145 backbone nodes, 20 metropolitan networks and coverage across 17 provinces and 80 cities. The authors also report six ground stations connected to the Jinan-1 quantum microsatellite. They describe an operational trusted-relay network and provide architecture and performance data.

Evidence and limitations

The figures and performance data come from a peer-reviewed paper written by researchers involved in the network. Publication establishes a documented technical account, not independent verification of every operational node or a guarantee of end-to-end security. Trusted-relay QKD requires trust in intermediate relay sites and is not equivalent to a quantum repeater network.

Assessment

The network illustrates the infrastructure and operations dimension of quantum communications, distinct from laboratory distance records. Subsequent records should test expansion claims against published network topology, service performance and independent operational evidence.

Why it matters

Long-distance QKD depends on deployed fibre, trusted facilities, classical networking and maintenance as well as quantum devices. The reported integration with Jinan-1 connects terrestrial and space-based research programmes.

Sources and cross-checks