cryptographic

Cryptographic refers to cryptography, the practice and study of techniques for secure communication in the presence of adversaries. It encompasses the design, analysis, and implementation of algorithms and protocols that protect information.

Core goals include confidentiality (keeping information secret), integrity (ensuring data is not altered), authentication (verifying identity), and non-repudiation (preventing denial of actions).

Cryptographic primitives include encryption algorithms for confidentiality, cryptographic hashes for data integrity, digital signatures for authentication and non-repudiation, and key exchange methods to establish shared secrets. These primitives are categorized as symmetric-key cryptography, which uses the same key for encryption and decryption, and asymmetric-key cryptography, which uses a public/private key pair. Examples: symmetric AES, ChaCha20; asymmetric RSA, elliptic-curve cryptography; hash functions like SHA-256.

Cryptographic protocols such as TLS, SSH, and PGP combine primitives to secure communications, authenticate parties, and ensure data integrity. Security of these systems relies on mathematical hardness assumptions and rigorous proofs in some cases, as well as careful implementation and random number generation. Cryptanalysis studies potential weaknesses, including algorithm flaws, protocol design flaws, and side-channel or implementation attacks.

The field continues to evolve with concerns about quantum computing and post-quantum cryptography; researchers develop algorithms believed resistant to quantum attacks to transition away from vulnerable primitives. Real-world deployment emphasizes standards, interoperability, and regular security assessments.