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The future's computers will crack Today's codes

Quantum computers will cut through the codes to your online banking, NemID (Danish national ID system), and email as if they were a hot knife through soft butter. Therefore, cryptologists from around the world are in a race against time. One of the sharpest in the field, Professor Lars Ramkilde Knudsen, works for the Center for Industrial Software (CIS) at the University of Southern Denmark in Sønderborg. And he says we need to keep our cool; we'll probably make it.

By Sune Holst, , 2/16/2024

"They might already be here."

This is what Professor of Cryptology Lars Ramkilde Knudsen says. The cryptologist made international headlines when, in 2003, he cracked the code within two days that was supposed to be used as the new standard for the FBI and government offices in Washington, among others. And when he says "they," he's talking about quantum computers. And why is that important for a cryptologist? We'll get to that.

Quantum computers are coming
A quantum computer is a type of computer that utilizes the principles of quantum mechanics to perform calculations. Unlike classical computers, which use bits to represent either 0 or 1, quantum computers use quantum bits or qubits, which can exist simultaneously in multiple states, thanks to superposition and entanglement phenomena. Quantum computers can perform complex calculations at a speed unachievable for classical computers.

Quantum computers can solve problems too complex for classical computers, such as optimization problems, material science, the development of new drugs, and complex cryptographic tasks.

"Quantum computers are a double-edged sword in cryptology. The same computational power that can accelerate scientific breakthroughs can also break cryptographic security, protecting everything from personal data to national security. Today's cryptographic algorithms, which secure everything from bank transactions to government communication lines, are designed with the computational limitations of classical computers in mind," says Lars Ramkilde Knudsen.

Old systems will fall
Today's cryptographic algorithms are based on systems called Public Key. In these systems, each user or device has a pair of keys: a public key and a private key. The two keys are mathematically related, but it is practically impossible to derive the private key from the public key.

"It was a revolution when it came out in 1976. Until then, you had to meet to exchange secrets," explains the 61-year-old professor.

It's about having two mathematically related keys and where you send one to your recipient, who can then read the encrypted message. The most known systems are RSA and Diffie-Hellman.

"They both build on the fascinating mathematics that initially lured me into the world of cryptology. It's the mathematics behind NemID, SSL/TLS protocols for secure web communication, VPNs, and many other forms of secure digital identification. But when quantum computers arrive, it all falls apart. We can't use it anymore."

A new defence is already being constructed
Quantum computers already exist to some extent. Google, Microsoft, IBM, and China have all developed the first nascent models of quantum computers. And IBM even allows you to use one of their quantum computers directly online. More mature models are expected to be ready within 10-20 years.


In Denmark, the Novo Nordisk Foundation has invested 1.5 billion kroner in a 12-year research program at the Niels Bohr Institute, which aims to give Denmark a fully functional quantum computer by 2034.

So, will hackers now have free access to your digital mailbox, email, and online banking?

"No, fortunately, there are systems believed to be unbreakable. This is what we call quantum-safe cryptology. A lot of money is being thrown at it right now. I believe we are safe."

The United States has the National Institute of Standards and Technology or NIST. NIST plays a central role in developing cybersecurity standards, including encryption and privacy protection guidelines.

One of NIST's essential roles is developing and recommending security standards and guidelines for federal agencies, but these standards are often also followed by the private sector. NIST's work in cryptology includes developing cryptographic standards, such as the Advanced Encryption Standard (AES) and guidelines for using cryptography, including recommendations for transitioning to quantum-resistant cryptology.

"The Americans realized a couple of years ago that this will go wrong at some point, so since then, cryptologists worldwide have been brainstorming and coming up with this system. There's talk about a system that is already known but has been adjusted to be fast and usable now. It's a fascinating area I am also spending some of my research time on."

With rising concerns about industrial espionage and cyberattacks from countries like Russia, Knudsen's research is not only relevant but vital.

"I don't think you should be worried if you're a bike mechanic with two employees, but large companies like Mærsk and Danfoss will have to arm themselves for this in the foreseeable future. Otherwise, they will be vulnerable."

Cryptologists will be in demand in the job market
In this context, there will be a scramble for cryptologists. There will be a widespread need for employees with the necessary skills to implement and maintain the new quantum-safe systems.

"That's why it's fortunate that we have established the Center for Industrial Software in Sønderborg as part of the Mærsk-McKinney Møller Institute. The first students started on September 1, 2023. We expected 30-40 applicants for our program. We admitted 111. That's fantastic. One of the tracks in education is cybersecurity. From 2025, we will offer cryptology courses that I will be in charge of," says Lars Ramkilde Knudsen.

Editing was completed: 16.02.2024