PostquantenKryptografie

PostQuantenKry... refers to Post-Quantum Cryptography, the branch of cryptography focused on algorithms believed to remain secure against quantum computer attacks. The driver is that powerful quantum algorithms, such as Shor’s algorithm, can break many widely used public-key systems (for example RSA and ECC), while quantum attackers could diminish the effectiveness of symmetric keys unless larger sizes are used. PQC seeks practical, standardizable public-key encryption, key exchange, and digital signatures that resist quantum adversaries, enabling secure communications in a quantum-enabled future.

Standardization and adoption efforts have been centralized in recent years. In response to the quantum threat, several national and international bodies launched evaluation programs to identify robust algorithms. In particular, major standardization efforts have focused on selecting algorithms for encryption and signatures that can replace or augment current schemes. By the early 2020s, several PQC candidates had matured into widely discussed standards, with public-key encryption and key encapsulation as well as digital signatures in view for standardization. The transition plan often includes hybrid deployments that combine a quantum-resistant algorithm with a traditional one during a gradual migration.

Algorithm families encompass several approaches. The leading area is lattice-based cryptography, including schemes used for key encapsulation and digital signatures. Other families include code-based cryptography, multivariate-quadratic-equations cryptography, and hash-based signatures. Each family offers different trade-offs in key sizes, computational requirements, and resistance to various attack models.

Practical deployment considerations include performance, key and ciphertext sizes, protocol compatibility, and resistance to side-channel attacks. Migration strategies emphasize interoperability, backward compatibility, and phased rollouts across protocols such as TLS and SSH. PQC remains a developing field, with ongoing research, testing, and standardization shaping its adoption in global security architectures.