µ2: A Lightweight Block Cipher

Abstract

This paper presents a 64-bit lightweight block cipher, µ2 with a key size of 80-bit. µ2 is designed based on well-established design paradigms, achieving comparable performance and security when compared against existing state-of-the-art lightweight block ciphers. µ2 is based on the Type-II generalized Feistel structure with a round function, F that is a 16-bit ultra-lightweight block cipher based on the substitution-permutation network. Security evaluation indicates that µ2 offers a large security margin against known attacks such as differential cryptanalysis, linear cryptanalysis, algebraic attack and others.