First UK quantum-secured long-distance video call completed

In a landmark achievement, researchers from the Universities of Bristol and Cambridge have successfully completed the United Kingdom’s first long-distance, ultra-secure video call over a quantum communications network.

As it happens, the quantum-secured video transmission took place over the existing standard fiber-optic infrastructure, integrating advanced quantum phenomena to ensure unprecedented data security, according to the report by the University of Cambridge published on April 8.

Specifically, the network employs two primary quantum key distribution (QKD) techniques – encryption keys embedded within particles of light, rendering them theoretically impossible to hack; and distributed entanglement, a quantum effect where particles become intrinsically linked regardless of distance.

How the UK’s first quantum-secured video call happened

To demonstrate the network’s capabilities, the researchers conducted a live quantum-secured video conference, transferred encrypted medical data, and enabled secure remote access to a distributed data center. All of these successfully spanned the distance between Bristol and Cambridge, covering more than 410 kilometers of fiber.

This also marks the first time that a long-distance network has effectively integrated various quantum-secured technologies, including entanglement distribution, alongside conventional data transmission, and the researchers demonstrated their findings at the 2025 Optical Fiber Communications Conference (OFC) in San Francisco.

Commenting on the breakthrough, co-author Dr. Rui Wang, Lecturer for Future Optical Networks in the Smart Internet Lab’s High Performance Network Research Group at the University of Bristol, had this to say:

“This is a crucial step toward building a quantum-secured future for our communities and society. (…) More importantly, it lays the foundation for a large-scale quantum internet – connecting quantum nodes and devices through entanglement and teleportation on a global scale.”

Meanwhile, the European Commission is about to start relying on quantum technologies to protect critical government and personal data, setting out to build an advanced quantum-secure space communications network for these purposes specifically.

Elsewhere, scientists at the Massachusetts Institute of Technology (MIT) in the United States have taken a massive step forward in quantum computing, developing a novel interconnect device that paves the way for scalable, all-to-all communication between superconducting quantum processors.