An improved RC6 algorithm with the same structure of encryption and decryption

In this paper, we propose an improved RC6 encryption algorithm that have the same structure of encryption and decryption. So far, conventional RC6 algorithms have difference structure of encryption and decryption. We devise our algorithm by inserting a symmetric layer using simple rotation and XOR operations, in which the half of whole RC6 rounds uses encryption procedure and the rest of it are employs decryption one. The symmetry layer is put between encryption part and decryption one. The proposed RC6 algorithm has the almost same speed compared with the conventional RC6 one. Nevertheless, the proposed algorithm improves encryption security by inserting the symmetric layer because a differential and linear analysis has a difficulty in analyzing an encrypted stream. The proposed algorithm will be useful to the applications which require the same procedure of encryption and decryption such as light mobile devices and RFIDs.