New Attacks against Reduced-Round Versions of IDEA

In this paper, we describe a sequence of simple, yet e cient chosen-plaintext (or chosen-ciphertext) attacks against reduced-round versions of IDEA (with 2, 2.5, 3, 3.5, and 4 rounds) which compare favourably with the best known attacks: some of them decrease considerably the time complexity given the same order of data at disposal while other ones decrease the amount of necessary known- or chosen-plaintext pairs under comparable time complexities. Additionally, we show how to trade time and memory for some of the known-plaintext attacks of Nakahara et al

New results on the genetic cryptanalysis of TEA and reduced-round versions of XTEA

Congress on Evolutionary Computation. Portland, USA, 19-23 June 2004Recently, a simple way of creating very efficient distinguishers for cryptographic primitives such as block ciphers or hash functions, was presented by the authors. Here, this cryptanalysis attack is shown to be successful when applied over reduced round versions of the block cipher XTEA. Additionally, a variant of this genetic attack is introduced and its results over TEA shown to be the most powerful published to date

Survey and Benchmark of Block Ciphers for Wireless Sensor Networks

Cryptographic algorithms play an important role in the security architecture of wireless sensor networks (WSNs). Choosing the most storage- and energy-efficient block cipher is essential, due to the facts that these networks are meant to operate without human intervention for a long period of time with little energy supply, and that available storage is scarce on these sensor nodes. However, to our knowledge, no systematic work has been done in this area so far.We construct an evaluation framework in which we first identify the candidates of block ciphers suitable for WSNs, based on existing literature and authoritative recommendations. For evaluating and assessing these candidates, we not only consider the security properties but also the storage- and energy-efficiency of the candidates. Finally, based on the evaluation results, we select the most suitable ciphers for WSNs, namely Skipjack, MISTY1, and Rijndael, depending on the combination of available memory and required security (energy efficiency being implicit). In terms of operation mode, we recommend Output Feedback Mode for pairwise links but Cipher Block Chaining for group communications