(CNBC) A little-known U.K. company called Arqit is quietly preparing businesses and governments for what it sees as the next big threat to their cyber defenses: quantum computers.
David Williams, co-founder and chairman of Arqit, says quantum computers will be several millions of times faster than classical computers, and would be able to break into one of the most widely-used methods of cryptography. “The legacy encryption that we all use to keep our secrets safe is called PKI,” or public-key infrastructure, Williams told CNBC in an interview. “It was invented in the 70s. “PKI was originally designed to secure the communications of two computers,” Williams added. “It wasn’t designed for a hyper-connected world where there are a billion devices all over the world communicating in a complex round of interactions.
Kasper Rasmussen, associate professor of computer science at the University of Oxford, told CNBC that quantum computers are designed to do “certain very specific operations much faster than classical computers.”
This could be a problem for modern encryption standards, according to experts.
“When you and I use PKI encryption, we do halves of a difficult math problem: prime factorisation,” Williams told CNBC. “You give me a number and I work out what are the prime numbers to work out the new number. A classic computer can’t break that but a quantum computer will.”
Williams believes his company has found the solution. Instead of relying on public-key cryptography, Arqit sends out symmetric encryption keys — long, random numbers — via satellites, something it calls “quantum key distribution.” Virgin Orbit, which invested in Arqit as part of its SPAC deal, plans to launch the satellites from Cornwall, England, by 2023.
The U.S. Commerce Department’s National Institute of Standards and Technology is looking to update its standards on cryptography to include what’s known as post-quantum cryptography, algorithms that could be secure against an attack from a quantum computer.
Williams thinks firms need to be ready now, adding that forming post-quantum algorithms that take public-key cryptography and make it “even more complex” are not the solution. He alluded to a report from NIST which noted challenges with post-quantum cryptographic solutions.