# Category Archives: security

## AES-128 / AES-256 Block Cipher

Introduction In January 1997, the National Institute of Standards and Technology (NIST) initiated a process to replace the Data Encryption Standard (DES) published in 1977. A draft criteria to evaluate potential algorithms was published, and members of the public were … Continue reading

## SHAKE-128 Stream Cipher

Introduction An Extendable-Output Function (XOF) absorbs input of variable length and generates output of variable length. SHAKE128 and SHAKE256 are two such XOFs designed by the Keccak team and included in the SHA-3 standard. They both use a sponge construction … Continue reading

## XTEA Block Cipher

Introduction TEA Extensions (XTEA) is a 64-bit block cipher with support for 128-bit keys. It was published in 1998 as a response to weaknesses found in the Tiny Encryption Algorithm (TEA) which was discussed previously in this post. XTEA compared … Continue reading

## BlaBla Stream Cipher

Introduction BlaBla is a 256-bit stream cipher designed by Jean-Philippe Aumasson. It uses the same permutation function as the cryptographic hash algorithm BLAKE2b, that is similar to the permutation function used in the ChaCha stream cipher, hence the name. Frank … Continue reading

## HIGHT Block Cipher

Introduction HIGHT which stands for HIGh security and light weigHT is a 64-bit block cipher with support for 128-bit keys. It was first proposed at the 2006 Cryptographic Hardware and Embedded Systems (CHES) conference held in Japan. HIGHT attracted a … Continue reading

## RoadRunneR Block Cipher

Introduction RoadRunneR is a 64-bit block cipher with support for 80 and 128-bit keys. It was designed by Adnan Baysal and Suhap Sahin and published in 2015. The 80-bit variant uses 10 rounds while the 128-bit uses 12. In this … Continue reading

## Ascon Permutation Function

Introduction Ascon is an Authenticated Encryption Associated Data (AEAD) algorithm submitted to the competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR) It was designed by Christoph Dobraunig, Maria Eichlseder, Florian Mendel and Martin Schläffer. Some of the authors mentioned … Continue reading

## Gimli: a cross-platform permutation function

Introduction Gimli, named after the Lord Of The Rings character, is a 384-bit cryptographic permutation function designed by Daniel J. Bernstein, Stefan Kölbl, Stefan Lucks, Pedro Maat Costa Massolino, Florian Mendel, Kashif Nawaz, Tobias Schneider, Peter Schwabe, François-Xavier Standaert, Yosuke … Continue reading

## PRESENT Block Cipher

Introduction PRESENT is a 64-bit block cipher published in 2007 that supports key lengths of 80 and 128-bits. It was designed by Andrey Bogdanov, Lars R. Knudsen, Gregor Leander, Christof Paar, Axel Poschmann, Matthew J. B. Robshaw, Yannick Seurin, and … Continue reading

## SM3 Cryptographic Hash Algorithm (Chinese Standard)

Introduction SM3 is 256-bit cryptographic hash algorithm derived from SHA-2 designed by the NSA. It was designed by Xiaoyun Wang who is responsible for discovering attacks against many cryptographic hash functions, most notably MD5 and SHA-1. At the CRYPTO 2004 … Continue reading