Substitution-Permutation Network (SPN) Ciphers

Substitution-Permutation Network (SPN) Ciphers are introduced as a modern approach to encryption, building upon the principles of substitution and permutation. SPN ciphers are characterized by a series of rounds where substitution and permutation operations are applied iteratively to the plaintext. The lecture delves into the structure and workings of SPN ciphers, highlighting their efficiency and security features. Key components such as substitution boxes (S-boxes), permutation layers, and the key schedule are discussed in detail, emphasizing their roles in enhancing the cipher's resistance to cryptanalysis. By studying SPN ciphers, students gain a comprehensive understanding of contemporary encryption techniques and their applications in securing digital communications and data. This knowledge serves as a crucial foundation for further exploration into advanced cryptographic algorithms and protocols.