While the construction of a quantum internet is still in its infancy, it should come as no surprise that a pioneer of the conventional internet is working to discover efficient ways to implement quantum technology.
Founded in 1984, Cisco played a vital role in the development of the Internet as we know it today. The network devices, internet connection solutions and associated communication technologies are based on the internet protocol, which is the data format used for transmitting data over a network or the internet.
In an academic paper titled, “Packet Switching in Quantum Networks: A Path to Quantum Internet,” released in May 2022, Cisco researchers propose using a mainstream Internet technology – packet switching – to quantum internet.
The promise of a quantum internet is that shared data will be secure and nearly impossible to hack, preserving the most valuable asset of businesses and governments: information.
The current difficulty is that quantum communication is rather cumbersome. Entities can send and receive quantum encoded information from point to point using reliable nodes at both ends of the transmission using technologies such as quantum key distribution (QKD). Teleportation and entanglement-swapping techniques are two more typical quantum network designs that are being explored today.
The difficulties in bridging continental distances, as well as the lack of efficiency with trusted nodes, and the requirement for back-to-back terminals, which is an expensive proposition at best, as well as a hard-to-realize mesh network cornerstone of all our advanced telecommunications networks, are perhaps the most critical architectural shortcomings of these approaches.
Building QKD-compliant networks within a limited metropolitan region has gained popularity in Europe, Japan and China, with China leading the world in QKD network installations. Unfortunately not so much in the United States. See my earlier post, “Why Public-Private Partnerships Can Accelerate the Adoption of QKD in the United States,” for more information.
But the current big concern in quantum research is how we can get to a quantum internet faster and more effectively.
And this is where Cisco’s exploration of the potential applications of packet switching gets intriguing. They propose taking a system that works in today’s complicated internet and adapting it to a quantum network.
To provide dynamic network routing, the traditional Internet relies on packet switching. Packet switching makes optimal use of network resources and is therefore the preferred design for the traditional Internet. It’s worth noting that as the world continues to explore the most effective designs for a quantum internet, some, like internet pioneer Cisco, are looking for ways the quantum internet can leverage the efficiency of packet switching.
In data transmission, packet switching divides a message into chunks. The bits are transported individually along the route available or best for that packet, then reassembled when they arrive at their destination.
This method makes optimal use of network resources and enables dynamic network routing.
Wouldn’t it be cool if we could use the structure of the current classical internet to kick start a hybrid classical/quantum internet?
Researchers are beginning to integrate packet switching efficiency with the quantum-safe features of QKD networks. An internet that combines the traditional efficiency of packet switching routing with the unparalleled security of QKD implies a marriage of the two technologies, resulting in a neoclassical quantum internet.
Essentially, such a hybrid network would require the traditional routing information included in the header of every packet processed by a packet switch. Still, the information in the package would be created in a quantum and secure manner using QKD. That’s an intriguing thought.
Still, the dilemma of how to overcome distance limits and reliable nodes with heavy hardware requirements remains.
For metropolitan-scale QKD networks, packet-switched QKD will first capture the efficiency of the conventional Internet architecture. This is a promising solution that appears to significantly reduce the high cost of trusted nodes using back-to-back hardware.
This is a step towards a more ubiquitous quantum internet, but we have to crawl first. Still, the fact that companies like Cisco, which gave birth to today’s Internet, think this way paints a dizzying picture of what can happen when industry leaders emerge.