Researchers affiliated with Cisco are making significant strides towards the establishment of functional quantum networks and data centers.
Recently, Cisco Research organized its Quantum Summit 2024, a gathering that attracted industry specialists to explore ongoing initiatives related to various aspects of quantum technology, including networking and security. However, it was the research into quantum data centers that captured the majority of Cisco’s attention.
According to Reza Nejabati, who leads quantum research within Cisco’s advanced development group known as Outshift, the envisioned quantum data center would possess the ability to execute multiple quantum circuits, support dynamic network connections, and implement diverse entanglement generation protocols, as he explained during a presentation at the summit.
“It is widely accepted in academic circles that simply scaling quantum computing to tens of millions of qubits is not a practical solution,” Nejabati noted.
“With the current advancements in technology, it appears to be more feasible to establish a network of smaller quantum computers. This essentially leads to the concept of a data center—creating a network that connects numerous smaller processors within a controlled setting, such as a data center warehouse, and offering them as a service to a wider range of users. That’s the fundamental concept behind a quantum data center,” explained Nejabati.
Cisco expressed earlier this year its vision for quantum data centers that could employ traditional local area network models along with fiber connections to link quantum computers. Alternatively, a quantum-based network could transfer quantum bits (qubits) from quantum servers at rapid speeds to accommodate commercial-grade applications.
“Simultaneously, the goal is to connect your quantum sensors and integrate them with devices like IoT. By linking them via a network, we can enhance sensing capabilities and accuracy, while also achieving distributed sensing for broader coverage,” Nejabati noted.
The aim is to avoid requiring customers to install a whole new network infrastructure for these tasks. Instead, it makes more sense to utilize the current fiber infrastructure, at least for quantum entanglement, while layering control and management capabilities on top of it, Nejabati indicated.
Cisco is actively advancing its own quantum entanglement network fabric named QFabric, which is intended to form the foundation of a quantum switch. This system is designed to facilitate the quantum entanglement process, bridging the connections between quantum computers and sensor interconnects, as stated by Nejabati. The switch is capable of non-blocking switching of entangled photons from numerous input ports to any output ports, accommodating various modes of entanglement. It will also boast ultra-low loss and minimal time jitter in port-to-port switching to maintain effective connectivity.
“Our ultimate goal is to accommodate a large number of users in a scalable, multi-tenant ecosystem through this dynamically switched quantum network,” Nejabati explained.
Beyond its networking capabilities, QFabric serves as the foundation for enabling quantum-safe networking. It is particularly well-suited for scalable key distribution.
“We are focused on creating a platform that enables a hybrid key management and distribution system, integrating post-quantum cryptography (PQC) and quantum key distribution (QKD),” Nejabati noted. “Moreover, any robust security solution hinges on a random number generator, and a truly perfect random number generator is crucial for effective cryptography. At Cisco, we have developed our own internal quantum random number generator.”
PQC incorporates intricate cryptographic algorithms designed to safeguard quantum computers against advanced threats.
“PQC is set to be embraced by browsers, operating systems, and libraries, while innovators will explore its integration into protocols such as SSL/TLS 1.3, which oversees traditional cryptography,” Cisco announced. “We will also see PQC gradually being adopted by enterprises striving to secure their data in the post-quantum era.”
The urgency for such protective measures is escalating due to worries that malicious entities are already utilizing attack strategies in anticipation of the vulnerabilities quantum computers may exploit in the future.
In addition to its work on the quantum network infrastructure, Cisco is creating a software suite that outlines optimal methods for entanglement, distribution, protocols, and routing algorithms, all of which will be developed within a protocol stack and compiler known as Quantum Orchestra.
“We are in the process of creating a network-aware quantum orchestrator, a comprehensive framework designed to handle quantum jobs specified as quantum circuits alongside the network topology, which outlines the distribution of various quantum devices across the network,” explained Hassan Shapourian, Technical Leader at Cisco Outshift. “This orchestrator will enable us to adjust a circuit for improved distribution. Additionally, we will determine the appropriate quantum variational circuit (QVC) to assign to specific quantum devices, as well as the communication paths between devices within a rack.”
“Next, we need to organize a series of switch configurations to facilitate end-to-end entanglement generation, ensuring reliable connectivity. This process includes both routing and resource management since we will be sharing resources. Ultimately, our aim is to reduce execution times or limit switching events, producing a set of instructions for the switches,” Shapourian added.
Shapourian noted that much of Cisco’s initial work on the Orchestrator has focused on simulations to evaluate the effectiveness of multi-tenancy and other functionalities, such as transmitting data through multiple quantum pathways rather than solely point-to-point connections. The company is expected to publish a paper detailing these findings later this year.
