Towards Low Energy Stream Ciphers

  • Subhadeep Banik LASEC, École Polytechnique Fédérale de Lausanne
  • Vasily Mikhalev University of Mannheim
  • Frederik Armknecht University of Mannheim
  • Takanori Isobe University of Hyogo
  • Willi Meier FHNW
  • Andrey Bogdanov DTU Compute, Technical University of Denmark, Lyngby
  • Yuhei Watanabe National Institute of Advanced Industrial Science and Technology, Osaka
  • Francesco Regazzoni University of Lugano
Keywords: Lightweight block cipher, Low energy, Stream Cipher


Energy optimization is an important design aspect of lightweight cryptography. Since low energy ciphers drain less battery, they are invaluable components of devices that operate on a tight energy budget such as handheld devices or RFID tags. At Asiacrypt 2015, Banik et al. presented the block cipher family Midori which was designed to optimize the energy consumed per encryption and which reduces the energy consumption by more than 30% compared to previous block ciphers. However, if one has to encrypt/decrypt longer streams of data, i.e. for bulk data encryption/decryption, it is expected that a stream cipher should perform even better than block ciphers in terms of energy required to encrypt. In this paper, we address the question of designing low energy stream ciphers. To this end, we analyze for common stream cipher design components their impact on the energy consumption. Based on this, we give arguments why indeed stream ciphers allow for encrypting long data streams with less energy than block ciphers and validate our findings by implementations. Afterwards, we use the analysis results to identify energy minimizing design principles for stream ciphers.

How to Cite
Banik, S., Mikhalev, V., Armknecht, F., Isobe, T., Meier, W., Bogdanov, A., Watanabe, Y., & Regazzoni, F. (2018). Towards Low Energy Stream Ciphers. IACR Transactions on Symmetric Cryptology, 2018(2), 1-19.