AES Variants Secure Against Related-Key Differential and Boomerang Attacks
In this paper, the authors summarize the recent related-key differential and boomerang attacks on AES by Biryukov et al. and present a framework for protection against these attacks. Then they study an alter-native AES key schedule proposed by May et al. at ACISP 2002 as a possible candidate to protect against these related key attacks. They find that there exist equivalent keys for this key schedule and in response; they propose an improvement to overcome this weakness. They proceed to prove, using the framework, that the improved May et al.'s key schedule is secure against related-key differential and boomerang attacks.