From individual test links to a larger network: Researchers have connected quantum communication networks in Thuringia, Bavaria, and Berlin for the first time. The successful demonstration, which marked the conclusion of the QuNET research initiative, shows how quantum-secure communication could work in the future even over longer distances and between different locations.
On October 28, 2026, the participating research institutions demonstrated how regional quantum networks can be interconnected. Minister President Mario Voigt officially launched the Thuringian subnetwork at the Fraunhofer Center in Erfurt.
An example from the healthcare sector illustrated how this might work in practice: Fictitious billing data was transmitted using quantum-secure encryption between Jena University Hospital, the IT service provider DATEV, and Bundesdruckerei. Various technical systems were used for this purpose, which were connected to one another via existing fiber-optic lines.
What makes this special is that, until now, many quantum communication methods have been tested primarily on individual test links. The quNET demonstration now shows how different regional networks can work together. This is an important prerequisite for building larger quantum networks in the long term—networks that connect, for example, hospitals, businesses, and government agencies.
This demonstration marks the conclusion of the QuNET research initiative, which was launched in 2019. The findings are expected to help advance quantum-secure communication from the research stage toward practical application.
For more information, visit: Pressemitteilung Fraunhofer IOF
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