On July 5th, the NIST (National Institute of Standard and Technology), the CNRS (National Center for Scientific Research) and the University of Limoges signed a license agreement the basis of patents developed in Limoges. “This license agreement, the result of a consultation process between the stakeholders involved, enshrines the excellence of French fundamental research at the global level. It particularly illustrates the quality of the French school in mathematics and cryptography.” is delighted Antoine Petit, Chairman and CEO of CNRS. “We are proud that researchers at our University are helping to define the future of digital security. The research team CRYPTIS from the XLIM laboratory confirms the global impact of its work in post-quantum cryptography.” welcomes Isabelle Klock-Fontanille, President of the University of Limoges.

Securing communications through cryptography

Cryptography is the science of secrecy. It is invisible, but it is present at all stages of our digital life. Whether when we make a payment on the internet or in everyday actions such as when we withdraw money from an ATM or during a Bluetooth connection. This ubiquity and invisibility is one of the great virtues of this technology and demonstrates the level of maturity and integration achieved in this field.

Cryptography operations are based on mathematical problems that are difficult to solve and would require several thousand years of computation to trace back to cryptography keys. The information is therefore readable only by the holders of the encryption keys. The cryptographic methods used today were developed in the late 1970s. They have been strengthened as computing technology has advanced, so cryptography keys have grown longer as time goes by.

The arrival of the quantum computer

However, even if they remain very robust in the face of the brute force of supercomputers, they become vulnerable if the attack was carried out with a quantum computer armed with the Shor algorithm. These computers were still only conceptual a few years ago, but in the last 4 to 5 years, the first quantum computers have begun to emerge from laboratories. Massive investments have been made around the world to achieve quantum superiority and roadmaps already indicate the availability of architectures with more than 100 Qubits in the years to come. Even if this already remarkable level of complexity remains very insufficient for the quantum computer to achieve useful performances, it is sufficient to make a threat go from “hypothetical” to “tangible”. Thus, for the most critical information or communications whose content must be kept secret over long periods of time, it becomes necessary to consider more robust methods of protection.

New Aquitaine accompanies the transition

This is why a transition is necessary to new cryptography techniques called “post-quantum”. The analysis of the security level and performance of the candidates allowed NIST to select one candidate (KYBER) from among four candidates in the final phase allowing the exchange of cryptographic keys. It was observed that two of the finalist solutions could be based on patent families filed as early as 2010 by teacher-researchers Philippe Gaborit and Carlos Aguilar-Melchor (University of Limoges and CNRS Xlim laboratory), and jointly owned by CNRS and the University of Limoges, and jointly owned by CNRS and the University of Limoges, which led to a licensing agreement with NIST. NIST has also kept four other protocols for a final round of analysis in order to further standardize. New Aquitaine cryptography researchers are very involved in two of these four candidates (HQC and BIKE).

In New Aquitaine, since October 2020, President Alain Rousset has launched the NAQUIDIS Center initiative, the partner to consider this post-quantum transition calmly. NAQUIDIS Center has made strong commitments in particular on:

• The creation of new businesses or new product opportunities for existing companies, through a strong mobilization of private and European investment mechanisms greater than several million Euros,
• The response to major societal challenges such as the fight against climate change and its effects, the forecasting of natural disasters, the management of natural resources, mobility, health, the security of communications and the fight against cyberattacks etc...