Secure quantum appli­ca­tions in Stuttgart’s real-world fiber optic network

The launch of the QCyber joint project gives the quantum ecosys­tem in Baden-Württemberg a strong boost in the field of quantum-secure commu­ni­ca­tion. Coordi­nated by the Univer­sity of Stuttgart and led by Prof. Stefanie Barz, QCyber is research­ing how quantum appli­ca­tions can be used securely and practi­cally in real networks with multi­ple users.

The project addresses a key challenge of digital sover­eignty: while quantum comput­ers could attack classic encryp­tion methods in the future, quantum commu­ni­ca­tion sets new standards in eaves­drop­ping security. QCyber goes a decisive step further by inves­ti­gat­ing not only point-to-point connec­tions, but also networks with up to six nodes over distances of up to 20 km in the Stuttgart fiber optic network.

The focus is on multi-user-capable quantum appli­ca­tions with high relevance for diplo­macy, finance, indus­try, and public administration—such as secure, anony­mous multi-party commu­ni­ca­tion, distrib­uted infor­ma­tion sharing only through the cooper­a­tion of multi­ple actors, “quantum e‑voting,” and approaches for future quantum-based cloud comput­ing. The aim is to combine basic research with concrete appli­ca­tion scenar­ios, thereby strength­en­ing Germany’s and Europe’s techno­log­i­cal sover­eignty in the field of IT security.

A special feature of QCyber is the field test in the real campus-wide fiber optic network in Stuttgart, which connects the Vaihin­gen and Stadt­mitte locations. In cooper­a­tion with the associ­ated partner Nokia, which provides additional test tracks, the hardware and software solutions devel­oped by the project partners are tested under real condi­tions and their integra­tion into exist­ing cyber­se­cu­rity archi­tec­tures is examined.

Poten­tial end users are involved at an early stage through workshops with indus­try partners at ARENA2036 on the Vaihin­gen campus. Possi­ble areas of appli­ca­tion range from secure vehicle-to-infrastructure commu­ni­ca­tion and the protec­tion of networked produc­tion facil­i­ties in smart facto­ries to confi­den­tial data trans­mis­sion between compa­nies, suppli­ers, and cloud services.

The QuantumBW innova­tion campus sees QCyber as a key project that combines the strengths of the Baden-Württemberg quantum ecosys­tem: excel­lent research, real-world test infra­struc­tures, and close ties with indus­try. The three-year initia­tive, funded with six million euros by the Federal Ministry of Research, Technol­ogy, and Space (BMFTR), lays an impor­tant founda­tion for secure infor­ma­tion process­ing of the future in the QuantumBW network.