IonQ deployed what it claims to be the largest and most complex quantum key distribution (QKD) network in Europe.

The initiative came out of a project with Romanian institutions, including the Politehnica University of Bucharest and the country’s RoEduNet national research and education network. It encompasses some 36 quantum-secured links spanning more than 932 miles (1,500 kilometers), connecting the capital of Bucharest with other major metropolitan areas, including Iași, Timișoara, Craiova, Cluj-Napoca, and Constanța.

Ionq claimed the project represents more than 20% of Europe’s terrestrial quantum communications infrastructure to date.

"This deployment of QKD at national scale supports critical security initiatives and protects sensitive communications across government, health care, research, education, and data center environments,” IonQ CEO Niccolo de Masi explained in a statement.

The nationwide network looks to protect critical communications against current and future cybersecurity threats, providing secure data movement via end-to-end distribution of encryption keys across a wavelength division multiplexing (WDM) network.

In total, some 12 Romanian universities, seven research institutes, three national agencies, and additional public and private stakeholders joined the effort, with QKD systems supplied by ID Quantique.

“Our newly deployed national QKD infrastructure is an important milestone both for Romania and for the EuroQCI effort,” Pantelimon George Popescu, head of the Quantum Computing Laboratory at Politehnica Bucharest, added. “This network establishes a practical foundation for secure data exchange across Romania and contributes to the broader European effort to build interoperable quantum communications networks."

The largest operational QKD network is believed to be in China, covering a total of 2,299 miles (3,700 km).

Detailed earlier in February, the Chinese Academy of Sciences and Peking University's School of Physics said the network consists of some 20 quantum chip nodes, which form a twin-field QKD network.

IonQ’s Euro-centric effort, meanwhile, is the latest in its quantum network efforts on the continent.

The firm recently teamed up with the Slovak Academy of Sciences to deploy Slovakia's first national quantum communication network, and also helped launch the Geneva Quantum Network in Switzerland.

The company also launched a wholly owned subsidiary in Italy to fuel continental quantum demands.