IBM is collaborating with Cisco to develop the groundwork for networked distributed quantum computing by the early 2030s.

An initial demonstration of the network is expected to be delivered in the next five years, with IBM stating that the project will help lay the groundwork for the quantum Internet, in addition to supporting quantum computing, sensors, and communications in the future.

Earlier this month, IBM said it will achieve quantum advantage by the end of 2026, and is on target to develop a fault-tolerant quantum computer by 2029.

If successful, the proof-of-concept will demonstrate a network that combines individual, large-scale, fault-tolerant quantum computers that can work together to run computations over tens to hundreds of thousands of qubits. For that initial demonstration, the companies will entangle qubits from multiple separate quantum computers located in distinct cryogenic environments.

However, achieving this will require IBM and Cisco to invent new connections, including microwave-optical transducers and a supporting software stack. Furthermore, scaling the network beyond two quantum computers will require the companies to explore how to transmit qubits over longer distances, such as between buildings or data centers.

IBM will develop a quantum networking unit (QNU), which will serve as the interface for its quantum processing unit (QPU). The QNU will take the stationary quantum information in the QPU and converting it into “flying” quantum information through the QNU to then be further linked across potentially multiple quantum computers through a network, IBM said in a statement.

The companies also plan to investigate how a network bridge, comprised of novel hardware and open-source software, could use Cisco quantum network nodes to link many IBM QPUs within a data center through its QNU interface, an approach that could be extended to link QPUs across multiple data centers in the future. This would scale a larger quantum network across even larger distances to form the groundwork for a future quantum computing internet.

“At IBM, our roadmap includes plans to deliver large-scale, fault-tolerant quantum computers before the end of the decade,” said Jay Gambetta, IBM fellow and director of IBM Research. “By working with Cisco to explore how to link multiple quantum computers like these together into a distributed network, we will pursue how to further scale quantum’s computational power. And as we build the future of compute, our vision will push the frontiers of what quantum computers can do within a larger high-performance computing architecture.”

Vijoy Pandey, GM/SVP at Outshift by Cisco, added: "Getting quantum computing to useful scale is not just about building bigger individual machines; it is also about connecting them together. IBM is building quantum computers with aggressive roadmaps for scale-up, and we are bringing quantum networking that enables scale-out. Together, we are solving this as a complete system problem, including the hardware to connect quantum computers, the software to run computations across them, and the networking intelligence that makes them work."