Toshiba Europe Restricted and Quantum Bridge Applied sciences (QBT) have demonstrated a global community able to quantum-safe knowledge transmission. The challenge combines Toshiba’s Quantum Key Distribution (QKD) expertise with QBT’s Distributed Symmetric Key Institution (DSKE) platform and was applied on present field-installed fibre infrastructure.
The demonstration, offered on the Optical Fiber Communication Convention 2026, reveals how metropolitan QKD networks may be related throughout continents utilizing DSKE. The method makes use of carrier-grade infrastructure and rising interoperability requirements to allow communication throughout lengthy distances with a concentrate on sustaining safety within the context of quantum computing developments.
The community relies on information-theoretic safety (ITS), often known as provable safety. This method is designed to guard delicate knowledge no matter an attacker’s computational sources, together with future advances in supercomputing and quantum computing.
Whereas QKD is deployed in metropolitan networks worldwide, extending it throughout continents presents challenges, together with the dearth of ultra-long-distance fibre QKD programs and restricted availability of satellite-based QKD.
One method to linking geographically separated QKD networks is post-quantum cryptography (PQC), which makes use of algorithms designed to withstand quantum computing assaults. PQC relies on computational assumptions that will evolve over time.
QBT’s DSKE expertise gives an alternate method for long-distance connections. It makes use of symmetric cryptography, secret sharing, and pre-shared entropy to ascertain keys with out counting on public-key infrastructure. This permits long-haul hyperlinks designed to take care of a stage of safety corresponding to QKD networks.
For the demonstration, a QKD community in Cambridge was related to a QKD community in Toronto. The programs have been hosted in Telehouse Canada knowledge centres and related utilizing present fibre infrastructure, demonstrating operation inside carrier-grade environments.
The challenge additionally included interoperability requirements from the European Telecommunications Requirements Institute (ETSI) Trade Specification Group on QKD. It used the ETSI GS QKD 020 Interoperable Key Administration Specification to allow communication between key-management programs in QKD and DSKE platforms, supporting interoperability between completely different distributors.
