Cisco Launches Quantum Network Controller to Build a Quantum Network Control Layer

en.Wedoany.com Reported - On October 6, Cisco released the Quantum Network Controller research prototype and simultaneously updated the Network-Aware Quantum Compiler. The new controller sits between quantum hardware and applications, and can automatically perform quantum network resource allocation, path configuration, link monitoring, and fault recovery based on the endpoints, entanglement rates, fidelity, and timing requirements specified by applications.

The controller adopts a hardware abstraction layer architecture, providing unified interfaces for entanglement sources, quantum switches, detectors, and timing systems, enabling quantum network equipment from different vendors to connect through the same control layer. Cisco calls this service model "entanglement as a service." Applications do not need to directly configure underlying optical devices; instead, they submit entanglement connection requirements to the controller, which continuously schedules devices and maintains connection states.

Quantum links cannot be monitored by directly reading data packets as traditional networks can. Cisco's controller verifies link quality through statistical methods. When performance deviates, it can retune, retry, or reinitialize according to preset policies; after an application task ends, the controller releases the corresponding hardware resources. The network-aware quantum compiler is responsible for splitting quantum computing tasks across different processors and converting the required nodes, entanglement quantities, and fidelity into network requests, which are then handed to the controller for execution.

This control layer is built on Cisco's previously released universal quantum switch. The universal quantum switch is responsible for routing quantum information between different quantum encoding modes and nodes, while the new controller further determines connection targets, resource allocation order, and runtime. According to Cisco's network model, if 1,000 quantum nodes were all connected in a point-to-point manner, nearly 500,000 independent links would be required. A shared switching fabric and centralized control layer are used to reduce this need for point-to-point connections.

In February of this year, Cisco software, together with partner equipment, completed multi-node quantum entanglement distribution and entanglement swapping tests on a 17.6-kilometer commercial communications fiber deployed in New York, achieving over 99% polarization fidelity at room temperature. The related tests used quantum hardware from multiple suppliers to verify the software's ability to coordinate heterogeneous devices and existing fiber networks.

Currently, the Quantum Network Controller remains a research prototype and has not entered standard commercial sales. Cisco is conducting actual network deployment validation with some partners and plans to accumulate operational data in real fiber environments over approximately the next two years, including fiber loss, vibration, environmental changes, and compensation mechanisms. The updated Network-Aware Quantum Compiler is currently available as a 30-day free trial.