Some of the encryption methods that protect internet traffic, email and financial transactions rely on the fact that factoring large numbers, or similar mathematical problems, is very hard for classical computers. Sufficiently powerful quantum computers, however, could solve these problems much faster using methods such as Shor’s algorithm. Post-quantum cryptography (PQC) is the umbrella term for new encryption methods that are resistant to this threat.
The “harvest now, decrypt later” risk
Today there are no quantum computers powerful enough to break current encryption. However, attackers could collect encrypted data today and wait to decrypt it in the future. For data that must remain confidential for many years (contracts, personal data, trade secrets), the risk therefore starts today.
The standards are set
In August 2024, the US National Institute of Standards and Technology (NIST) published the first post-quantum cryptography standards: ML-KEM (FIPS 203) for key exchange, and ML-DSA (FIPS 204) and SLH-DSA (FIPS 205) for digital signatures. Software and hardware vendors have started adding these standards to their products.
What can companies do today?
- Build a cryptography inventory: List which encryption methods are used in which systems.
- Define the confidentiality lifetime of your data: Classify how many years each type of data must remain confidential.
- Aim for crypto-agility: Design systems so that encryption methods can be replaced easily.
- Talk to your suppliers: Ask about the PQC roadmap of the software and services you use.
- Plan a gradual transition: Hybrid approaches that combine classical and post-quantum methods are emerging as the norm during the transition period.
Conclusion
The move to post-quantum cryptography is a transformation that will take years. Companies that start early will both reduce their risk and complete the transition at a lower cost. Through our quantum programming service , we will continue to share our work in this area.