Expert Marcos Curty: ‘A quantum computer can crack all of our current cryptography’

Marcos Curty has a doctorate in telecommunications and doesn’t own a cell phone. He says that it is a deliberate and personal choice. Curty aims to transform his hometown, Vigo (northwest Spain), into a global center for security in quantum computing, a significant challenge for this technology. Throughout his international academic career, this professor of signal theory and communications has collaborated with top experts in the field. Together, they have established the Quantum-Safe Internet network, a cybersecurity training center, and the Quantum Communication Center at the University of Vigo. These research initiatives involve companies and universities from various countries, and aim to position Vigo as a key player in the quantum world. The Quantum Communication Center has received nearly $11 million (€10 million) in funding from Spain’s Ministry of Science, the regional government of Galicia, and various European research funds, as well as support from companies like Cisco.

Question. Is our current system secure?

Answer. To ensure the security of our communications, we rely on cryptographic techniques. These methods are commonly used in applications that connect to the internet and banking services. Whether it’s in government, business or military communications, confidentiality is crucial to prevent unauthorized access. With the increasing volume of transmitted information over open networks, protecting data has become more critical than ever. Currently, public key cryptography methods are predominantly used, relying on complex mathematical problems for security. With the advent of quantum computers, many complex problems will become easier to solve, including functions used in cryptography.

Q. Thirty years ago, Peter Shor, a mathematician at the Massachusetts Institute of Technology, cautioned that a quantum computer could efficiently solve factorization problems.

A. His statement implies that with a quantum computer, all the cryptography currently used on the internet could be broken. One example is factorization, which is a fundamental part of many cryptographic systems. There are other math problems used in cryptography that can also be compromised by a quantum computer. That’s why the concept of a Quantum-Safe Internet is important — it focuses on developing strong cryptographic methods to address this challenge.

Q. Is the current development of new security technologies also leading to the emergence of new forms of attack?

A. With increased computing power, previously challenging problems can become more manageable. Post-quantum cryptography explores tasks that quantum computers may struggle to efficiently solve. Certain algorithms have already been identified and are set to become standard soon, though we can’t yet provide guarantees.

Q. In fact, some of the latest algorithms designed to prevent quantum computer attacks have been defeated using classic computers and even laptops.

A. Yes, those algorithms have advantages, as they enable us to continue using our current infrastructure. However, it’s possible that in the future, someone might develop a highly efficient algorithm that can access past data retroactively. Therefore, these solutions are more suitable for short-term applications.

Q. Is there another way?

A. An alternate solution is based on quantum communications, which offers security against any computer and enables fully secure communications. When you send information over a communication channel that you don’t control, it can be copied. However, in quantum mechanics, this isn’t possible. When information is encoded in elementary particles in specific states, any attempt to copy it introduces detectable noise. Additionally, unlike conventional methods, there is no certainty that a reproduced copy is authentic. This level of security is independent of computational capacity.

Q. And that's where the University of Vigo comes in?

A. We’ve begun a research initiative in Spain and have formed two highly esteemed international groups at the Quantum Communication Center. One group, led by Professor Hugo Zbinden from the University of Geneva, has been at the forefront of quantum communications since the 1990s. They have achieved remarkable breakthroughs and established the current record for maximum transmission distance. The other group, headed by Professor Vadim Makarov of the Quantum Hacking Lab, specializes in certification standards for quantum communication equipment and hacking concerns. While quantum cryptography is absolutely secure in theory, it must be developed very carefully. Makarov is a renowned international expert in identifying and resolving vulnerabilities in these systems.

Q. Is Vigo going to be the capital of quantum security next year?

A. I’d love to say so. Currently, there are very few or no initiatives in the field of quantum communications that match the talent we have at the University of Vigo.

Q. Could the participation of experts from nations in conflict pose a security issue?

A. Our work involves conducting research that will be publicly available in scientific publications, so I see no problem with having an international team.

Q. Will there be quantum communications from space?

A. The European Space Agency has various programs focused on low-orbit satellites. In Spain, the University of Vigo collaborates with Hispasat [the operating company for a number of Spanish communications satellites that cover the Americas, Europe and North Africa] to assess the potential of quantum communication links using high-orbit satellites.

Sign up for our weekly newsletter to get more English-language news coverage from EL PAÍS USA Edition