Cisco Systems and quantum networking startup Qunnect have successfully built and operated a quantum communication network between Brooklyn and Manhattan using existing fiber optic cables.
The experiment demonstrated that quantum signals can be transmitted across real-world urban infrastructure with performance comparable to laboratory conditions. Qunnect’s hardware combined with Cisco’s software addressed key technical barriers involved in integrating quantum systems into current city-based data center environments.
Quantum computers rely on the principles of quantum physics to perform calculations far beyond the reach of traditional machines. However, they typically require complex cryogenic cooling systems. Qunnect’s approach simplifies this requirement by using cryogenic cooling only at a central hub, while connected data centers operate using room-temperature equipment.
The system remained stable across a 17.6-kilometer fiber link thanks to automatic polarization controllers that corrected environmental disturbances such as vibration and signal degradation.
The development is seen as a foundational step toward linking quantum computers within data centers and eventually building a large-scale quantum internet.
In the near term, quantum networks could enable ultra-fast coordination between distant computing systems, including applications in financial trading and high-speed decision-making processes.
