Quantum signals move across commercial fibre using IP, showing integration with existing internet systems.
Researchers at the University of Pennsylvania transmit quantum signals over commercial fibre-optic networks using the same Internet Protocol (IP) that manages today’s web traffic. The experiment runs on Verizon’s campus fibre system, demonstrating quantum networking on standard infrastructure.
The team developed the Q-Chip, which coordinates both classical and quantum signals. The system packages information into IP-style packets, with ‘header’ on each packets, while the quantum information rides behind in sealed containers enabling routing and switching with the same addressing and management tools used in conventional networks. The chip also corrects for noise without disturbing the quantum state, using information embedded in the accompanying classical signal.
Unlike conventional communication, quantum communication relies on entangled particles, whose states typically collapse when measured, making routing and error correction difficult. So, by coupling a measurable classical “header” with the quantum signal, the Penn team enables the quantum data to move through the network without being destroyed.
The chip is tested over one kilometre of commercial fibre between two buildings, maintaining transmission fidelity above 97%. The setup includes a single server and node but can be scaled by fabricating additional chips and connecting them to existing fibre networks.
The approach addresses challenges such as temperature changes, vibrations, and noise that normally disrupt quantum signals outside laboratory conditions. Scaling beyond metro areas, however, remains limited by the inability to amplify quantum states without destroying their entanglement.
