PRESENT

PRESENT is a lightweight block cipher, developed by the Orange Labs (France), Ruhr University Bochum (Germany) and the Technical University of Denmark in 2007.  PRESENT is designed by Andrey Bogdanov, Lars R. Knudsen, Gregor Leander, Christof Paar, Axel Poschmann, Matthew J. B. Robshaw, Yannick Seurin, and  C. Vikkelsoe.  The algorithm is notable for its compact size (about 2.5 times smaller than AES). 

Overview

The block size is 64 bits and the key size can be 80 bit or 128 bit.  The non-linear layer is based on a single 4-bit S-box which was designed with hardware optimizations in mind.  PRESENT is intended to be used in situations where low-power consumption and high chip efficiency is desired.  The International Organization for Standardization and the International Electrotechnical Commission included PRESENT in the new international standard for lightweight cryptographic methods. 

Cryptanalysis
A truncated differential attack on 26 out of 31 rounds of PRESENT was suggested in 2014. 

Several full-round attacks using biclique cryptanalysis have been introduced on PRESENT. 

By design all block ciphers with a block size of 64 bit can have problems with block collisions if they are used with large amounts of data.  Therefore, implementations need to make sure that the amount of data encrypted with the same key is limited and rekeying is properly implemented. 

References

External links
 PRESENT: An Ultra-Lightweight Block Cipher
 http://www.lightweightcrypto.org/implementations.php Software Implementations in C and Python
 http://cis.sjtu.edu.cn/index.php/Software_Implementation_of_Block_Cipher_PRESENT_for_8-Bit_Platforms C implementation
 http://www.emsec.rub.de/media/crypto/veroeffentlichungen/2011/01/29/present_ches2007_slides.pdf Talk slides from Cryptographic Hardware and Embedded Systems

Category:Block ciphers
Category:Cryptography