====== 3.1 What is Post-Quantum Cryptography? ======

Protection against future quantum computer attacks.

===== The Problem =====

Today's encryption (RSA((RSA Algorithm: https://en.wikipedia.org/wiki/RSA_(cryptosystem))), ECC((Elliptic Curve Cryptography: https://en.wikipedia.org/wiki/Elliptic-curve_cryptography))) is based on mathematical problems that are hard to solve for normal computers. Quantum computers((Quantum Computing Fundamentals: https://www.ibm.com/topics/quantum-computing)) could solve these problems in minutes instead of millennia - using Shor's Algorithm((Shor's Algorithm: https://en.wikipedia.org/wiki/Shor%27s_algorithm)).

===== The Threat =====

**"Harvest Now, Decrypt Later"**((ENISA: Post-Quantum Cryptography - Current State: https://www.enisa.europa.eu/publications/post-quantum-cryptography-current-state-and-quantum-mitigation))

Attackers collect encrypted data today and wait for powerful quantum computers to decrypt it later.

Affects:
  * Trade secrets
  * Long-term contracts
  * Personal data
  * Health data

===== The Solution =====

**Post-Quantum Cryptography (PQC)**((NIST Post-Quantum Cryptography: https://csrc.nist.gov/Projects/post-quantum-cryptography))

New encryption methods that even quantum computers cannot break. These are based on different mathematical problems:

  * **Lattice-based**: ML-KEM((FIPS 203 (ML-KEM): https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.203.pdf)), ML-DSA((FIPS 204 (ML-DSA): https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.204.pdf))
  * **Hash-based**: SLH-DSA((FIPS 205 (SLH-DSA): https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.205.pdf))
  * **Code-based**: Under evaluation

===== Timeline =====

^ Year ^ Event ^
| 2024 | NIST Standards((NIST PQC Standards: https://www.nist.gov/news-events/news/2024/08/nist-releases-first-3-finalized-post-quantum-encryption-standards)) published |
| 2025 | EU Roadmap((EU PQC Recommendation: https://digital-strategy.ec.europa.eu/en/library/recommendation-coordinated-implementation-plan-transition-post-quantum-cryptography)) and first implementations |
| 2030 | EU deadline for critical infrastructure (NIS2((NIS2 Directive: https://eur-lex.europa.eu/eli/dir/2022/2555/oj))) |
| 2035 | NIST deprecates classical algorithms((NIST: Transition to PQC: https://csrc.nist.gov/projects/post-quantum-cryptography/post-quantum-cryptography-standardization)) |

===== WvdS PQ-Crypto Library =====

EMSR DATA provides a ready-to-use .NET library for Post-Quantum Cryptography:

  * [[..:..:..:..:..:pqcrypt:start|PQ-Crypto Overview]]
  * [[..:..:..:..:..:pqcrypt:konzepte:algorithmen:start|PQ Algorithms Explained (ML-DSA, ML-KEM)]]
  * [[..:..:..:..:..:pqcrypt:api:start|API Reference]]

===== Sources =====

  * [[https://www.nist.gov/news-events/news/2024/08/nist-releases-first-3-finalized-post-quantum-encryption-standards|NIST PQC Standards (August 2024)]]
  * [[https://www.enisa.europa.eu/publications/post-quantum-cryptography-current-state-and-quantum-mitigation|ENISA Post-Quantum Cryptography Report]]
  * [[https://csrc.nist.gov/Projects/post-quantum-cryptography|NIST PQC Project]]
  * [[https://www.ibm.com/topics/quantum-computing|IBM: What is Quantum Computing?]]