New Attacks Against Reduced-Round Versions of IDEA
نویسنده
چکیده
In this paper, we describe a sequence of simple, yet efficient 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 knownor 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.
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