External Publication

Cisco sees quantum networking as the future of networking

Network World [Unofficial] June 3, 2026

Particle entanglement, superposition and teleportation are key concepts in quantum physics. Einstein famously dismissed such phenomena as “spooky action at a distance.”

Quantum computing is the nascent field of technology bringing that spookiness to life, but it is quantum networking that will actually enable quantum computing to be useful by connecting multiple systems together. According to Cisco, quantum networking’s practical utility isn’t limited to quantum computing, and it can have a material impact on the regular networks we use today.

In a deep-dive session at Cisco Live, Ramana Kompella, head of Cisco Research and Cisco Fellow, detailed precisely what quantum networking is, how it works at a theoretical level, and what Cisco is building to enable real world applications.

During his session, Kompella made the case that the bottleneck to practical quantum computing is not the processor. It is the network connecting processors together. His argument drew directly from the history of classical infrastructure: The same scale-out methodology that built the modern internet could, he said, accelerate the arrival of useful quantum computing by decades.

“Quantum networking can accelerate the arrival of practical quantum computing by decades by using the scale-out methodology that we’ve used successfully in our classical infrastructure,” Kompella said.

How quantum networking actually works

The starting point is understanding why quantum networks cannot be built like classical ones.

“Quantum networking is completely different from classical networking,” Kompella said.

In a classical network, data moves as packets through switches and routers. In a quantum network, information is not transported directly. Instead, the network distributes entangled photon pairs between nodes. Entanglement links two photons so that measuring the state of one instantly determines the state of the other, regardless of the distance between them.

The qubit : Where classical computing processes data as bits, ones and zeros, quantum computing uses qubits, units of quantum information that exploit a property called superposition. Superposition means a qubit can represent a one, a zero, or any combination of both at the same time, until it is measured. That ability to hold multiple states simultaneously is what gives quantum computers their computational potential. Each entangled photon pair can transfer exactly one qubit of information.

Quantum teleportation : Rather than sending a qubit directly across a wire, quantum networking uses entangled photon pairs to transfer quantum information from a sender to a receiver. The process is called teleportation because the qubit effectively disappears at one end and reappears at the other without physically traveling the intervening distance.

The speed-of-light caveat : Teleportation sounds instantaneous, and in one sense it is, but the receiver still cannot use the arriving qubit until a classical signal arrives confirming how to interpret it. That classical signal travels at the speed of light. Information does not move faster than light.

The hardware: What Cisco has built

With those fundamentals in place, the question becomes how to build infrastructure that delivers entanglement at scale. Cisco has developed two pieces of hardware designed to answer that question.

The entanglement source : Announced last May, Cisco’s entanglement source generates 200 million entangled photon pairs per second. It operates at standard telecom frequencies, which means it runs over existing fiber infrastructure rather than requiring a dedicated quantum fiber plant. It also runs at room temperature, with no cryogenic hardware required.

The Universal Quantum Switch : The centerpiece of Kompella’s session was a chip he pulled from his shirt pocket: a prototype of the Cisco Universal Quantum Switch, built from thin film lithium niobate.

“I’ve seen people pulling out pluggables from their pockets all the time,” Kompella said. “I get a chance to pull it out of my pocket to showcase the quantum switch chip.”

width="1024" height="566" sizes="auto, (max-width: 1024px) 100vw, 1024px">

Ramana Kompella, head of Cisco Research and Cisco Fellow, holds a prototype of the Cisco Universal Quantum Switch at Cisco Live 2026.

Cisco

Standard optical switching hardware cannot be used in a quantum network. It disturbs the fragile quantum states being transmitted. The Cisco switch is built specifically to preserve quantum information through the switching operation.

The universality in its name comes from modality conversion. Quantum computers are not all built the same way. Superconducting, neutral atom, ion trap and photonic systems each encode quantum information differently, using polarization, time bin, frequency bin and other modalities. A switch that handles only one encoding type locks an operator into a single hardware vendor. The Cisco Universal Quantum Switch converts between modalities, so a single fabric can interconnect heterogeneous quantum processors.

“We are building the switch and fabric in order to actually interconnect all of them, not just any one type,” Kompella said.

Architecture: the quantum data center model

Cisco’s architecture puts the switch at the center of a pod-based topology that mirrors classical data center design: processors and shared resources grouped into pods, interconnected through layers of switching.

Entanglement protocols are required. Three protocols handle end-to-end entanglement between quantum processors:

Emitter-Scatterer: One side emits a photon that interacts with a matter qubit on the receiving end.
Emitter-Emitter: Both sides emit photons that meet at a Bell State Measurement Device.
Scatter-Scatter: Two entanglement sources achieve transitive entanglement across two measurement points.

Each protocol suits different hardware configurations.

A distributed compiler is also required. A large quantum circuit cannot run on a single processor today. Cisco’s distributed quantum compiler partitions circuits across multiple processors and manages execution across the network. It also handles distributed error correction through syndrome measurement, a non-destructive operation that detects and corrects erroneous qubits without collapsing quantum states, extended to the network layer to ensure the interconnect does not introduce new errors into the computation.

Classical applications that benefit now

Kompella also addressed a question that goes beyond quantum computing: Can classical networking applications benefit from a quantum network today? Two properties make that possible. The first is entanglement. The second is the no-cloning theorem, which states that quantum information can be moved but not copied.

Quantum Sync : Two trading desks separated by tens of kilometers want to execute coordinated buy or sell decisions simultaneously. In a classical network, one side sends a message and waits for a response, and at the microsecond timescales of high-frequency trading, that propagation delay matters. With an entangled state between the two nodes, both sides make a joint decision without waiting for a message to cross the link. Kompella said the approach carries a 10% to 15% advantage over any classical coordination scheme.

Quantum Alert : The threat is harvest now, decrypt later: An attacker taps the fiber, collects encrypted packets, and waits for a quantum computer capable of breaking the encryption. Quantum Alert multiplexes entangled photons onto existing classical fiber. Both endpoints perform joint measurements, producing correlated detections called coincidences. A dip in coincidences signals that photons are being absorbed. An attacker cannot inject replacement entangled photons, so the pattern breaks regardless.

“That’s what makes this foolproof against an eavesdropper,” Kompella said.

From lab to live fiber, and what comes next

Cisco has moved beyond controlled environments. Working with a partner called Connect, Cisco ran entanglement-swapping experiments over live operational fiber in New York.

“We got much better rates than what lab results actually look like,” Kompella said.

On the computing side, Cisco has announced partnerships with IBM and, more recently, Atom Computing, a neutral-atom quantum computing vendor. The collaboration spans the software stack, distributed error correction and transduction, which is the process of converting quantum information between different physical carrier types, with the goal of stitching heterogeneous quantum nodes into a single end-to-end network.

The partnerships reflect the same architectural logic as the Universal Quantum Switch. Cisco is not betting on one quantum computing modality winning. It is building the interconnect layer that works regardless of which one does.

“Quantum networking has many practical and commercial use cases in the classical world today,” Kompella said.