An ultra compact block cipher for serialized architecture implementations

In this paper, we present a new block cipher, referred as PUFFIN2, that is designed to be used with applications requiring very low circuit area. PUFFIN2 is designed to be implemented exclusively with CMOS technologies and in a serialized architecture, so that the maximum reuse of hardware components is achieved resulting in a very compact implementation. PUFFIN2 has a block size of 64 bits and a key size of 80 bits. Compared with a serialized implementation of cipher PRESENT, which has the same block size and key size and is claimed as the smallest practical block cipher implementation to date, our cipher has 16% fewer gates using the same CMOS technology. Further, PUFFIN2 inherently supports both encryption and decryption while the serialized PRESENT is an encryption-only implementation.