Just weeks after the IT and networking giant revealed that it had developed software designed to make the new networking paradigm work through networking application demos for classical use cases, Cisco has announced a partnership with IBM to build a network of large-scale, fault-tolerant quantum computers, laying the groundwork for networked distributed quantum computing, to be realised as soon as the early 2030s.
The two firms believe that distributed quantum networks could lay the groundwork towards a quantum computing internet defined by quantum computers, sensors and communication in the late 2030s.
By combining IBM’s expertise in building quantum computers with Cisco’s quantum networking development work, the companies plan to explore how to scale large-scale, fault-tolerant quantum computers. Additionally, they plan to work to solve fundamental challenges towards a quantum computing internet.
Within five years, IBM and Cisco will aim to demonstrate the first proof-of-concept for a network that combines individual, large-scale, fault-tolerant quantum computers, enabling them to work together to run computations over tens to hundreds of thousands of qubits. They believe such a network could allow problems to be run with potentially trillions of quantum gates, the fundamental entangling operations required for transformative quantum applications such as massive optimisation problems, or the design of complex materials and medicines.
The companies are targeting an initial proof of concept demonstration by the end of 2030, for which they plan to entangle qubits from multiple separate quantum computers located in distinct cryogenic environments. Doing so, the companies argue, will require them to invent new connections, including microwave-optical transducers and a supporting software stack.
To scale beyond linking two quantum computers that are separate but physically close, IBM and Cisco are additionally planning to explore how to transmit qubits over longer distances, such as between buildings or datacentres. To achieve this, the companies will explore optical-photon and microwave-optical transducer technologies and investigate how they can be incorporated into a quantum network to transfer quantum information as needed.
The firms also say that to link together multiple quantum computers, an appropriate interface will be necessary. IBM plans to build a quantum networking unit (QNU) to serve as the interface to a quantum processing unit (QPU), with the explicit task of taking 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 and Cisco also intend to explore the development of quantum hardware and software that could physically link many large-scale, fault-tolerant quantum computers to form networked distributed quantum computing.
Commenting on the partnership, Jay Gambetta, director of IBM Research and IBM fellow, said its roadmap includes plans to deliver large-scale, fault-tolerant quantum computers before the end of the decade.
“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,” said Gambetta.
Vijoy Pandey, general manager and senior vice-president at Outshift by Cisco, said getting quantum computing to a useful scale is not just about building bigger individual machines, it is also about connecting them.
“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 it work,” said Pandey.
