About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
ITNG 2022
Conference paper
Optimized implementation of Rijndael256 on modern x86-64 platforms
Abstract
The Advanced Encryption Standard (AES) was standardized in 2001 by NIST and has become the de facto block cipher used today. AES is a block cipher with a block size of 128 bits and is based on the proposal by Rijmen and Daemen, named “Rijndael”. The Rijndael proposal includes a definition for a block cipher with 256 bits block size (and a 256-bits key), which we call here Rijndael256. This variant has not been standardized. This paper describes software optimization methods for fast computations of Rijndael256 on modern x86-64 platforms equipped with AES-NI and with vector AES-NI instructions. We explore several implementation methods and report a speed record for Rijndael256 at 0.27 cycles per byte.