Paper 2018/1143

A new SNOW stream cipher called SNOW-V

Patrik Ekdahl, Thomas Johansson, Alexander Maximov, and Jing Yang


In this paper we are proposing a new member in the SNOW family of stream ciphers, called SNOW-V. The motivation is to meet an industry demand of very high speed encryption in a virtualized environment, something that can be expected to be relevant in a future 5G mobile communication system. We are revising the SNOW 3G architecture to be competitive in such a pure software environment, making use of both existing acceleration instructions for the AES encryption round function as well as the ability of modern CPUs to handle large vectors of integers (e.g. SIMD instructions). We have kept the general design from SNOW 3G, in terms of linear feedback shift register (LFSR) and Finite State Machine (FSM), but both entities are updated to better align with vectorized implementations. The LFSR part is new and operates 8 times the speed of the FSM. We have furthermore increased the total state size by using 128-bit registers in the FSM, we use the full AES encryption round function in the FSM update, and, finally, the initialization phase includes a masking with key bits at its end. The result is an algorithm generally much faster than AES-256 and with expected security not worse than AES-256.

Available format(s)
Secret-key cryptography
Publication info
Published by the IACR in FSE 2020
SNOWStream Cipher5G Mobile System Security
Contact author(s)
alexander maximov @ ericsson com
2019-08-27: last of 2 revisions
2018-11-29: received
See all versions
Short URL
Creative Commons Attribution


      author = {Patrik Ekdahl and Thomas Johansson and Alexander Maximov and Jing Yang},
      title = {A new SNOW stream cipher called SNOW-V},
      howpublished = {Cryptology ePrint Archive, Paper 2018/1143},
      year = {2018},
      note = {\url{}},
      url = {}
Note: In order to protect the privacy of readers, does not use cookies or embedded third party content.