This paper presents the block cipher Midori that is optimized with respect to the energy consumed by the circuit per bit in encryption or decryption operation. We deliberate on the design choices that lead to low energy consumption in an electrical circuit, and try to optimize each component of the circuit as well as its entire architecture for energy. An added motivation is to make both encryption and decryption functionalities available by small tweak in the circuit that would not incur significant area or energy overheads.
We propose two energy-efficient block ciphers Midori128 and Midori64 with block sizes equal to 128 and 64 bits respectively. These ciphers have the added property that a circuit that provides both the functionalities of encryption and decryption can be designed with very little overhead in terms of area and energy. We compare our results with other ciphers with similar characteristics: it was found that the energy consumptions of Midori64 and Midori128 are by far better when compared ciphers like PRINCE and NOEKEON.Category / Keywords: secret-key cryptography / AES, lightweight block cipher, low energy circuits Original Publication (with minor differences): IACR-ASIACRYPT-2015 Date: received 25 Nov 2015, last revised 25 Nov 2015 Contact author: subb at dtu dk Available format(s): PDF | BibTeX Citation Version: 20151127:175133 (All versions of this report) Short URL: ia.cr/2015/1142 Discussion forum: Show discussion | Start new discussion