A collaboration between Quantum Communications Hub researchers and their German colleagues has enabled a quantum-secure conversation to take place between four parties simultaneously. The demonstration, led by Hub researchers based at Heriot-Watt University and published in Science Advances, shows that totally secure conference calls that cannot be hacked can be realised. This is especially pertinent in light of reports of significant escalation of cyber-attacks on popular teleconferencing platforms in the last year.
Senior author, Professor Alessandro Fedrizzi, who led the team at Heriot-Watt, said: "We've long known that quantum entanglement, which Albert Einstein called 'spooky action at a distance' can be used for distributing secure keys. Our work is the first example where this was achieved via 'spooky action' between multiple users at the same time – something that a future quantum internet will be able to exploit."
Secure communications rely upon the sharing of cryptographic keys. The keys used in most systems are relatively short and can therefore be compromised by hackers, and the key distribution procedure is under increasing threat from quickly advancing quantum computers. These growing threats to data security require new, secure methods of key distribution.
A mature quantum technology called Quantum Key Distribution (QKD), deployed in this demonstration in a network scenario for the first time, harnesses the properties of quantum physics to facilitate guaranteed secure distribution of cryptographic keys.