What is quantum?
"Quantum physics is the set of physical laws that govern the behavior of the world at the level of electrons, atoms, molecules, and crystals," explains Alain Aspect, Nobel Prize in Physics 2022, in Polytechnique Insights.
A quantum computer is a major application of the second quantum revolution, which began in the 1970s and enabled the observation and control of micro- and nanoscopic objects individually. Unlike classical computers that use bits (0 and 1), quantum computers use qubits (or quantum bits), which can exist in superposition—meaning they can be in combinations of 0 and 1 simultaneously. This property provides an advantage for certain algorithms, allowing them to be executed much faster, with greater precision, and using less energy. Today, however, qubits remain unstable and quickly lose the information they contain (a phenomenon called decoherence).
Why could quantum computing change everything?
The UN has designated 2025 as the International Year of Quantum Science and Technology. Quantum science and technology promise numerous future applications, so much so that the French government has implemented a highly ambitious national quantum strategy to ensure the country a place among the leading players in the sector. As part of this strategy, the Ministry of the Armed Forces has also launched the PROQCIMA program, which aims to have at least two universal quantum computer prototypes available by 2032.
Quantum computers, coupled with supercomputers, could offer numerous opportunities in a variety of fields, such as discovering new drugs, simulating materials, optimizing financial portfolios, strengthening the resilience of telecommunications networks, and optimizing supply chains.
“However, the performance of future quantum computers could break current public key cryptography. Protecting ourselves from this threat is essential and urgent,” warns Usman Javaid, Director of Products and Marketing at Orange Business.
What is the quantum risk in numbers?
The threat to current cryptography is very real. It targets public key protocols, known as asymmetric protocols, such as RSA, Diffie-Hellman, and ECC, which ensure authentication, encryption key exchanges, and the protection of our Internet connections, email exchanges, financial transactions, and electronic signatures. Symmetric key protocols such as AES are less exposed, but must also be reevaluated to ensure lasting security.
According to a study by US digital trust provider Digicert, 69% of companies recognize the threat that quantum computing could pose. However, only 5% have begun to prepare for it. In 2024, cybercrime cost French companies an estimated €100 billion (Statista, 2024). 67% of them were victims of at least one cyberattack in 2024, compared to 53% in 2023 (Hiscox Report, 2024).
When is Q-Day?
Q-Day is the day when quantum computing will become powerful enough to break current asymmetric cryptography systems.
Current encryption systems could therefore be completely vulnerable by 2034 (Gartner Report, 2024). Hence, the urgent need to migrate to new, more complex algorithms, known as post-quantum cryptography (PQC). Security agencies, including the US NIST, recommend completing the migration of critical applications by 2030 and the rest by 2035.
NIST recommends phasing out RSA 2048 and ECC 256 from common use by 2030, with the goal of eliminating them by 2035 in order to accelerate the transition to post-quantum cryptography. Some analysts estimate that Q-Day could occur between 2030 and 2035. Orange Business is already taking steps to prepare its customers for this transition.
How can we prepare for the quantum threat?
To protect themselves, all companies must move towards PQC – post-quantum cryptography.
Migrating to post-quantum cryptography will not happen overnight. This transition must be initiated as soon as possible. To cope with the quantum tsunami and ensure business continuity for the public sector and businesses, Orange offers a suite of secure solutions called Orange Quantum Defender. “This is a first-of-its kind service in France” comments Aliette Mousnier-Lompré, CEO of Orange Business. “This is a significant step in the Orange multi-layer quantum-safe networking strategy, as we help our enterprise customers respond to the growing and evolving security threats from quantum computing". These services are structured around:
- consulting services: Orange Cyberdefense's Cyber Consulting, which aims to support companies in their migration to post-quantum cryptography (PQC) and provide them with crypto-agility recommendations.
- provision of secure networks and infrastructure by Orange Business Services for its enterprise customers.
For some highly critical applications, Orange Business and Toshiba Europe launched the first commercial quantum secure network service last June. It uses quantum key distribution (QKD) backed by post-quantum cryptography to provide complete protection by detecting espionage attempts.
“Built on the robust technology by Toshiba, we are not just protecting sensitive data today; we are prepared and ready to partner with our customers for a secure and resilient future.” said Aliette Mousnier-Lompré, CEO of Orange Business, at the launch.
PQC stands for Post-Quantum Cryptography: post-quantum cryptography consists of a set of cryptographic algorithms including key establishment and digital signatures. This complex set provides essential protection against the quantum threat (ANSSI, 2025).
QKD as Quantum Key Distribution. Quantum key distribution consists of securely exchanging encryption keys between two endpoints, ensuring that any interception of the key can be detected.
SNDL as Store now, Decrypt later. Also known as “Harvest now, decrypt later,” this practice adopted by attackers focuses on acquiring and storing currently unreadable encrypted data in anticipation of Y2Q or Q-Day, the advent of sufficiently powerful quantum computing.
Asymmetric cryptography (public key): a system in which each entity has a pair of keys—a public key, known to everyone, and a private key, kept secret. The public key is used to encrypt data or verify a signature; the private key is used to decrypt that data or sign.
RSA: public key cryptography algorithm based on the difficulty of factoring integers. It is commonly used for encryption, digital signatures, and key exchange.
Diffie–Hellman (DH): key exchange protocol based on the logarithm problem.
Elliptic curve cryptography (ECC): a family of methods based on the discrete logarithm problem on elliptic curves. It offers security equivalent to RSA with shorter keys.
