cryptography

What cryptographic schemes Shor's algorithm threatens, what post-quantum schemes replace them, the math behind lattice-based cryptography, the NIST standardization process and its outputs, and the operational mechanics of a real-world cryptographic migration.

AES and block ciphers are primitive building blocks, not complete encryption schemes. Learn how ECB leaks structure, why CBC and CTR modes work differently, and why GCM is the modern default — including the catastrophic consequences of nonce reuse.

Trapdoor functions power every TLS handshake, code signature, and SSH session. Master RSA key generation and its math, why textbook RSA is trivially broken, what elliptic curves add, and how ECDSA and Ed25519 compare — with key-size equivalences you can quote in code reviews.

Every HTTPS connection negotiates a fresh secret over an untrusted network. Learn Diffie-Hellman and ECDH from first principles, why forward secrecy matters when private keys leak, how TLS 1.3 cut the handshake to one round-trip, and how certificate chains stop man-in-the-middle attacks.

Hash functions are not all equal and MACs are not just hashes with a secret. Learn the three resistance properties, why length-extension attacks break naive HMAC constructions, how KDFs differ from hashes, and why bcrypt/scrypt/Argon2 exist for passwords.