A Small and Efficienct Hardware Implementation of the KASUMI

KASUMI is a block cipher with the Feistel network. This paper proposes a small and efficiency hardware implementation for the KASUMI block cipher, which is the core of the 3GPP confidentiality algorithm f8, and the 3GPP integrity algorithm f9. In designing the hardware, we focused on optimizing the implementation of FO/FI functions, which are the main components of KASUMI. We propose three methods for this optimization: using a loop-structure in the implementation to reducing the number of the FO/FI function, implementing S7 and S9-boxes in the combinational logic and optimization of extended key´s generation.