Cisco recently rolled out a quantum networking software layer built atop its quantum photonics chip, a move that seeks to deepen integration between quantum and classical infrastructure. The company has long operated in classical networking, but now it’s trying to make quantum networks accessible to the classical world, tells IEEE Spectrum.
At the heart of Cisco’s approach is a chip that can generate entangled photon pairs over standard fiber lines at telecom wavelengths, a key step, because it allows quantum signals to ride the same physical infrastructure as classical traffic. Combined with that, Cisco’s new compiler enables users to program quantum-classical hybrid applications using IBM’s Qiskit language. The compiler handles low-level connectivity, error-correction tradeoffs, and path selection across qubit nodes transparently.
The motivation isn’t just quantum computing. Cisco sees quantum networks as a platform for secure communications (because entanglement can detect eavesdropping), ultra-precise timing synchronization, quantum sensing, and other emerging applications. One immediate use case is embedding quantum signals alongside classical data to protect fiber links.
Still, implementing quantum networks at scale is hard. Optical fiber attenuates photons over distances, and quantum bits (qubits) cannot be cloned in flight, a fundamental limit. Cisco’s system can manage around 100 kilometers with high fidelity today. To push farther, the industry needs quantum repeaters and long-lived quantum memories.
Experts see Cisco’s entry as validating quantum networking’s importance. While research has focused heavily on quantum computing, investments in networking have lagged. Cisco brings decades of networking expertise to an area where routing, multiplexing, and protocol layering are essential.
Cisco is not inventing quantum networking from scratch, but it’s creating a bridge. By hiding complexity behind software, supporting hybrid use cases, and using existing fiber infrastructure, it may fast-track how classical systems evolve toward quantum readiness.