Paper 2013/404

The SIMON and SPECK Families of Lightweight Block Ciphers

Ray Beaulieu, Douglas Shors, Jason Smith, Stefan Treatman-Clark, Bryan Weeks, and Louis Wingers


In this paper we propose two families of block ciphers, SIMON and SPECK, each of which comes in a variety of widths and key sizes. While many lightweight block ciphers exist, most were designed to perform well on a single platform and were not meant to provide high performance across a range of devices. The aim of SIMON and SPECK is to fill the need for secure, flexible, and analyzable lightweight block ciphers. Each offers excellent performance on hardware and software platforms, is flexible enough to admit a variety of implementations on a given platform, and is amenable to analysis using existing techniques. Both perform exceptionally well across the full spectrum of lightweight applications, but SIMON is tuned for optimal performance in hardware, and SPECK for optimal performance in software.

Available format(s)
Secret-key cryptography
Publication info
Published elsewhere. Unknown where it was published
lightweight block cipher
Contact author(s)
djshors @ tycho ncsc mil
2013-06-20: received
Short URL
Creative Commons Attribution


      author = {Ray Beaulieu and Douglas Shors and Jason Smith and Stefan Treatman-Clark and Bryan Weeks and Louis Wingers},
      title = {The SIMON and SPECK Families of Lightweight Block Ciphers},
      howpublished = {Cryptology ePrint Archive, Paper 2013/404},
      year = {2013},
      note = {\url{}},
      url = {}
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