Presentation 2000/1/25
Strength of Round function in RC6 Block Cipher against Higher Order Differential Attack
Hidema TANAKA, Hiroshi TANAKA, Toshinobu KANEKO,
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Abstract(in English) RC6 is a new block cipher; a candidate of AES, proposed by Rivest et al in 1998. AES version of RC6 has 20 rounds and 32[bit] word length. In this paper, we estimate strength of Round function in RC6 against Higher Order Differential Attack. Since RC6 uses Sub-keys by integer addition, we show that it has weak keys which enable attacks using lower order differentials. We estimate its strength by calculating the ratio of weak keys. If weak keys are used, attacks are feasible, so the ratio of weak keys equals to the probability of successful attack. As the results, we found that 5 round Round function is attackable using 16th order differential with about 1.5×10^<-4>% of successful attack. And 6 round Round function is attackable using 32nd order differential with higher probability than 2^<-32>. This attack needs 2^<32> chosen plain texts and 2^<64> computational cost.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) Block cipher / RC6 / Higher Order Differential Attack / Weak key
Paper # ISEC99-77
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Conference Information
Committee ISEC
Conference Date 2000/1/25(1days)
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Paper Information
Registration To Information Security (ISEC)
Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) Strength of Round function in RC6 Block Cipher against Higher Order Differential Attack
Sub Title (in English)
Keyword(1) Block cipher
Keyword(2) RC6
Keyword(3) Higher Order Differential Attack
Keyword(4) Weak key
1st Author's Name Hidema TANAKA
1st Author's Affiliation Department of Electrical Engineering, Science University of TOKYO()
2nd Author's Name Hiroshi TANAKA
2nd Author's Affiliation Department of Electrical Engineering, Science University of TOKYO
3rd Author's Name Toshinobu KANEKO
3rd Author's Affiliation Department of Electrical Engineering, Science University of TOKYO
Date 2000/1/25
Paper # ISEC99-77
Volume (vol) vol.99
Number (no) 584
Page pp.pp.-
#Pages 7
Date of Issue