How Cisco's quantum networking software advances solutions classical applications cannot achieve

At Cisco Quantum Labs, we are actively transforming quantum mechanics principles into tangible solutions, bridging the gap between the quantum realm and everyday classical applications, solving problems that were previously impossible through classical networks.

This focus on classical applications is more important than ever. Classical networks hit limits: Data encryption struggles with harvest now, decrypt later attacks; sophisticated algorithms and infrastructure require instant coordination of data and action that today rely on imperfect networks.

We are developing a common set of networking protocols and software based on entanglement to provide entirely new Quantum Networking-based capabilities to classical use cases that are impossible to provide via a classical network.

Let’s dive into the mechanics of entanglement and how we’re showcasing the future it holds for classical computing with our new application demonstrations.

What is quantum entanglement, and why does it matter?

At its core, quantum entanglement is a phenomenon where two particles become intrinsically linked, sharing a joint quantum state. This bond means that measuring one particle determines the state of the other, regardless of the distance separating them. While it doesn't allow for faster-than-light communication, it creates instantaneous and always-accurate "nonlocal correlations" that classical physics cannot explain.

Key features of entangled particles that make them so powerful include:

• Shared state: The two particles form a single, inseparable quantum state. From that point on, they change together.
• Quantum correlations: Due to this shared state, measurements on one particle instantaneously influence the other. No lag, no error.
• No cloning: The quantum state cannot be copied, and measurement collapses its quantum properties. No interference or outside manipulation is possible.

These unique characteristics are what allow quantum entanglement to revolutionize areas like time synchronization, secure communications, position verification, and distributed decision coordination – bringing a level of accuracy, speed and security to these high-value classical applications that wasn’t possible so far.

Stacking up the case for an accelerated timeline to applied quantum networking

Cisco Quantum Labs is at the forefront of developing the hardware and software necessary to realize a robust Quantum Networking infrastructure. Our goal is to provide high-rate, high-fidelity entanglement distribution over a scalable, multi-tenant, multi-user architecture. Put simply, we aim to build a unified Quantum Networking platform that allows for any quantum node to interact with any other quantum node.

The release of our Quantum Network Entanglement Chip prototype earlier this year was the first step towards enabling practical Quantum Networking. The chip operates at standard telecom wavelengths, boasting an ultra-high pair generation rate (>200M entangled pairs/second) and exceptional fidelity rate of ~99% at less than 1mW of power. With a practical deployment approach in mind, the chip functions at room temperature and is extremely energy efficient.

Crucially, Quantum Networking hardware advancements alone aren't enough. To build scalable Quantum Networking, we need corresponding device abstractions, control protocols and network applications – i.e., a network software stack. Combined with physical devices, our vision for a complete software stack will deliver quantum connectivity services like entanglement distribution and teleportation between any quantum endpoints. 

The stack delivers capabilities in three layers: 

1. Device abstraction, including SDKs for physical devices, as well as emulated and simulated devices, 
2. A control layer to manage such devices, provide relevant protocols, 
3. Network applications.

We believe our comprehensive stack architecture across the three layers of apps, control protocols, devices is what makes Quantum Networking not only realistic and practical on an accelerated timeline for enterprises but is ready to deliver results even today for some classical applications needs that most businesses grapple with. 

Quantum network applications for classical problems: Security and coordination

To demonstrate the power of this unified software stack and our entanglement-enabled network hardware, we're showcasing two groundbreaking demo use cases:

1. Quantum Alert: Eavesdropper protection

Modern telecom networks, while robust, remain vulnerable to physical tapping, spoofing, or tampering. Classical security measures often fail to detect sophisticated physical tapping attacks.

Quantum Alert leverages the inherent sensitivity of entangled quantum systems. Any attempt to eavesdrop, spoof, or tamper with an entangled quantum system (e.g., entangled photons) will disturb and break the entanglement. This immediate collapse serves as a tamper-proof alarm signal, providing real-time detection of unauthorized access or intrusion.

This works alongside existing encryptions, such as newer post-quantum cryptography (PQC) encryption or the older, non-quantum-safe encryption. 

Watch the following demo of Quantum Alert to see a real-world example of its security capabilities:

Potential use cases include: Protecting critical communication links and fiber infrastructure in financial services, telecom, defense, and critical utility infrastructure.

2. Quantum Sync: Decision coordination

Many advanced applications, such as high-frequency trading or distributed robotics, require multiple geographically distributed entities to make correlated decisions without the delays of real-time communication. Classical communication, even over optical fiber, introduces latency.

Quantum Sync offers a revolutionary alternative. It provides a shared nonlocal resource where a "decision variable" is shared in advance via entangled particles. At the moment of decision, no signaling is required; each node simply measures its entangled particle. The outcomes are correlated through nonlocal correlations, effectively eliminating propagation delay and the need for multi-round consensus protocols.

Watch the following demo of Quantum Sync to see how instantaneous coordination occurs using our quantum network simulator with real protocols:

Potential use cases: High-frequency trading synchronization, defense mission-critical environment coordination, and distributed AI/robotics for coordinating nonlocal agents.

The Quantum future is now

Cisco's advancements in Quantum Networking are not just about theoretical possibilities; they are about building practical, secure, and high-performance solutions with both current and future challenges in mind. Our systems-level approach to Quantum Networking is building a full solution–from silicon to integrated hardware and all the layers of software required to manage it–from the ground up, paving the way for a new era of classical computing applications enhanced and enabled by the unique properties of quantum entanglement.

If you are a researcher and/or are exploring enterprise applications of Quantum Networking for classical use cases and have interest in further exploring the power of Quantum Alert or Quantum Sync in your environment, send us a message to speak with our team to discuss your particular use case and a possible design partnership.

Watch the fifth annual Cisco Quantum Summit on the Outshift YouTube channel to revisit the progress we've made from compilers to classical applications:

• Day One – Network-aware Quantum Compiler for scaling Quantum Computing  
• Day Two – Quantum Network supporting Classical Applications