Paper 2015/585

SIMON and SPECK: Block Ciphers for the Internet of Things

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

Abstract

The U.S. National Security Agency (NSA) developed the SIMON and SPECK families of lightweight block ciphers as an aid for securing applications in very constrained environments where AES may not be suitable. This paper summarizes the algorithms, their design rationale, along with current cryptanalysis and implementation results.

Note: We've updated Table 1 to include recent SIMON cryptanalysis results from Chen and Wang (2015/666). We've also edited the discussion of low-latency implementations, to include a PRINCE implementation from 2015/658, fix a reference, update one of our implementations, and tweak the wording.