QuINSiDa - Quantum-based infrastructure networks for safety-critical wireless data communication

Modern quantum technology opens up many new application areas. But it also poses risks. For example, quantum computers, thanks to their enormous computational power, could undermine even the most advanced data encryption methods. To forestall this scenario, Fraunhofer IPMS and several partners, led by KEEQuant GmbH, are developing a new approach to secure optical data transmission in wireless networks using light and quantum keys.

Linking Li-Fi technology and quantum cryptography

Li-Fi technology allows users to network with each other over short distances using optical signals. Compared to the well-known Wi-Fi technology, which is based on radio waves, the optical signals do not penetrate walls and can thus be designed to cover a defined area. In addition, Li-Fi technology allows full utilization of the available spectral data bandwidth.

Independently of this, quantum key distribution (QKD) is being promoted worldwide, which makes it possible to distribute a cryptographic key whose security can be proven on the basis of information theory. In quantum key distribution, quantum states in the form of light are prepared and exchanged between the participants in the network when the keys are generated. When the quantum states are received, they are measured and post-processed to produce keys that are identical on both sides but secret to an attacker.

The QuINSiDa project is the first to combine both technologies into a "QKD over Li-Fi" system. This makes it possible to carry QKD, which has so far been more typically envisaged in the building-to-building scenario, right through to the end user.