Symmetric and Asymmetric Cryptography Questions

Covers the foundational differences, constructions, and trade offs between symmetric key cryptography and public key cryptography. Candidates should understand block cipher and stream cipher design, authenticated encryption and modes of operation such as Electronic Codebook, Cipher Block Chaining, Counter mode, and Galois Counter Mode, key sizes and security margins, and practical use cases for symmetric schemes. For public key cryptography candidates should understand the mathematical bases and purposes of schemes such as Rivest Shamir Adleman and elliptic curve based constructions, how key agreement and digital signatures work, and why hybrid protocols combine public key operations with symmetric encryption. Interviewers probe algorithm selection, performance and latency trade offs, key distribution patterns, and secure deployment recommendations.