Atul Mantri

Security of Key-Alternating Ciphers: Quantum Lower Bounds and Quantum Walk Attacks

2024 · arXiv (Cornell University)

We study the quantum security of key-alternating ciphers (KAC), a natural multi-round generalization of the Even--Mansour construction. KAC abstracts the round structure of practical block ciphers as public permutations interleaved with key XORs. The $1$-round …