Today’s quantum computers are stuck at hundreds of qubits when real-world applications need millions. We can either wait decades for perfect quantum processors, or we can network existing ones together now. We believe the time is now.

Today we’re announcing software that makes distributed quantum computing work. We’re releasing three research prototypes to advance Cisco’s quantum networking strategy:

Quantum Compiler: The industry’s first network-aware, distributed quantum compiler enabling quantum algorithms to run across multiple networked processors. As part of this, we are also announcing an industry-first compiler supporting distributed quantum error correction.
Quantum Alert: An application demo for eavesdropper-proof security with guarantees from physics, not promises from classical software.
Quantum Sync: A decision coordination application demo that uses entanglement to enable correlated decision-making across distributed locations for classical use cases.

All three applications run on a unified quantum networking software stack, which is the vital infrastructure that makes quantum computers work together instead of alone.

At our virtual Quantum Summit next week, hosted by the Cisco Quantum Labs research team, we will demonstrate everything live and make the Quantum Compiler prototype available for download.

Building the Complete Quantum Networking Stack

At Cisco, we have always believed in a full-stack approach to building robust, high-performing systems. For classical networking, we design and build this stack from the ground up—custom silicon, integrated hardware systems, and all the layers of software that control and manage everything. It’s the philosophy that enabled us to pioneer many of the foundational technologies of the classical internet, from the core of the data center to the edge of wireless networks, and all the connectivity in between.

We are taking that same systems-level approach to quantum networking. Just as we did for the classical internet, we’re building a full networking stack from the ground up: developing a quantum networking chip, control software including protocols and controllers for managing the network, and quantum networking applications that solve problems in the quantum and classical worlds.

After announcing our quantum network entanglement chip which generates 200+ million entangled photon pairs per second, we are now pleased to announce the software that makes quantum networking actually work.

Our unified quantum networking software stack has three layers of capabilities:

Applications include quantum networking applications for quantum and classical use cases. We are announcing the code availability of a network-aware distributed quantum computing compiler that enables efficient execution of quantum algorithms in a networked quantum data center;
Control layer that contains quantum networking protocols and algorithms to both support the broad set of quantum networking applications as well as manage the wide set of devices (hardware and software) that make up a quantum network through well-defined northbound and southbound APIs; and,
Devices layer that consists of an SDK and APIs to physical devices as well as a library of emulated and simulated ones.

Cisco’s Quantum Compiler Prototype: A Network-Aware Compiler for Quantum Circuits

Part of what we are releasing next week is the first Quantum Compiler designed for distributed quantum computing across networked processors. This compiler enables efficient and scale-out execution of circuits across multiple processors in a Quantum Data Center. It achieves this through quantum circuit partitioning and scheduling the entanglement generation and distribution to facilitate quantum state transfer across these processors.

What makes it unique (and an industry first) is that it accounts for quantum interconnect requirements between processors and supports distributed quantum error correction. Existing compilers only target circuits for single computers. Ours compiles circuits for network-connected computers potentially made of heterogeneous quantum compute technologies and can distribute that partitioned circuit across an entire data center of processors, all connected through a quantum network.

If an organization is building scalable and operable quantum computing infrastructure, they need this capability to right-size and figure out how many quantum nodes they will need, and what types of compute technologies work best for the various parts of their algorithm. For example, pharmaceutical companies need this to run drug discovery algorithms that are too large or complex for single machines; financial firms need it for simulations that require different types of computational power and for scoping their infrastructure, and research institutions need it for innovating new quantum algorithms and compute types.

Solving Classical Use Cases through Quantum Networks

While many in the industry debate when quantum compute technologies will deliver true business value, Cisco’s quantum networking application demos for classical use cases show that the time is now.

Quantum Alert (provable eavesdropper detection) uses quantum physics to detect when bad actors are eavesdropping on organization traffic. When entangled photons are distributed through a quantum network, any attempt to intercept the communication changes the quantum properties and triggers an immediate alarm. It works alongside existing encryptions such as post-quantum cryptography (PQC) standards or other cryptographic schemes. Quantum Alert protects against harvest-now-decrypt-later attacks as a layer beside any software-based scheme.

Quantum Sync (decision coordination) uses quantum entanglement so distributed systems can take correlated decisions without sending messages. Think of it as two nodes—Alice and Bob—with each getting a special, pre-correlated coin in a box. If Alice opens the box and finds a “heads” on her coin, Bob is guaranteed to find a “tails.” An example use case for Quantum Sync is in high-frequency trading where milliseconds equal millions and financial institutions risk losing money to coordination problems every day. Our demonstration uses our quantum network simulator with real protocols.

Making Quantum Networking Real

The teams at Cisco Quantum Labs and Outshift by Cisco have built a complete software solution prototype for controlling, managing, and monitoring entanglement-based quantum networks across applications both in the quantum and the classical computing spaces. Our approach works with any quantum computing platform, whether superconducting, trapped ion, photonic or any other. Just like Cisco did for the classic internet.

Join us virtually at our free event, the Cisco Quantum Summit, next week on September 30 and October 1, 2025. You will be able to see the compiler in action, watch the demos, and learn how to start experimenting with these technologies yourself. The complete technical details and download links will be available at the Summit. Register for the Summit today and be part of the next chapter in quantum networking history.