To future-proof data and thwart hackers using quantum-based technologies, Verizon conducted trials deploying a quantum key distribution (QKD) network and tested quantum-safe virtual private networks (VPNs), while internally preparing its networks against post-quantum threats.

Verizon tested the QKD network deployment in the Washington D.C. area in 2020 and the company is working on another one in the Boston area, Lee Sattler, distinguished engineer in product strategy and operations at Verizon, told SDxCentral, claiming it’s one of the first carriers to pilot QKD in the U.S.

During the first trial, quantum keys were created and exchanged over a fiber network using a QKD network between three Verizon locations in D.C.

“We wanted to trial this on production fiber, so real-life fiber, not something in the lab,” Sattler said, adding that QKD is “one of the first quantum applications that we can actually try in the field.”

The biggest challenge for the deployment is the distance limitation, “because the quantum communications are very fragile,” he noted. “Currently, we're looking at maybe between 60 to 80 miles that one can go, and that's quite limiting over fiber, so we're looking at what one could do with quantum repeaters in the future when they become available and how we could extend the distance of quantum communications.”

This challenge limits the QKD rollout within a metropolitan area, “but when we get to a point where we have quantum internet and we build that up to a point where it is continental, then we could build something across the nation,” Sattler said.

As a number of QKD vendors based on different variations of the technology continue to emerge, Verizon plans to see “which technologies are going to shine the best,” then productize the QKD technology and put it into the vendor’s own network.

The equipment for the QKD network has to have a high degree of availability, “and part of that is that whole FCAPS model — fault management, configuration management, accounting, performance, security, all those things need to be in place,” Sattler said. “When we put something in our central offices, it has to be rock solid.”

Verizon’s Post-Quantum Crypto Efforts

In addition to the QKD trials, Verizon also explored data protection methods using post-quantum cryptography (PQC).

The company tested how a quantum-safe VPN can replace the current public key encryption methods to establish encryption keys using PQC. It successfully sent keys or ciphers across long distances without relying on QKD.

As far as commercialization, Verizon plans to wait for the National Institute of Standards and Technology (NIST) and other standard bodies to finalize the PQC standards, Sattler noted.

The company is also assessing its own encryption assets. “We've been doing proof of concepts with some of the [PQC algorithm] candidates,” he said. “Per the recommendations from the NSA, we would not implement PQC until the standards are final. But we're putting ourselves in a position that we'll be able to do that.”

And Sattler noted Verizon is working with other telecom carriers and industry groups to develop a quantum-safe strategy.

AT&T AVP of Security Dan Solero told SDxCentral in an earlier interview that it has set the goal to become “quantum ready” by the year 2025.

“Even before the standards are finalized, it is going to be a huge effort, especially in the carrier network,” Sattler said. “We have not just our enterprise network, but we also have a network that we run for a customer, so it's important to us that we're ready to move forward when we can.”