MKV: a new block cipher for the post-quantum cryptography transition

In this paper, we propose MKV (standing for “Mã Khối Việt Nam” in Vietnamese, meaning "Block Cipher of Vietnam"), a new block cipher designed to support quantum migration within Vietnam's Civil Cryptography sector. First, we present the MKV specification. Then, we analyze its design strategy. The block cipher employs a structure based on the Four Leaf Clover (FLC) scheme. It incorporates new cryptographic components within the FLC-SDS structure, which represents a specific FLC instantiation using Substitution-Diffusion-Substitution round functions. This design achieves provable security from both theoretical and practical aspects. Next, some results of cryptanalysis for MKV are introduced. Finally, some experimental results on the implementation of MKV are presented.