On tameness of matsumoto-imai central maps in three variables over the finite field F2

Keisuke Hakuta, Hisayoshi Sato, Tsuyoshi Takagi

Research output: Contribution to journalArticle


Triangular transformation method (TTM) is one of the multivariate public key cryptosystems (MPKC) based on the intractability of tame decomposition problem. In TTM, a special class of tame automorphisms are used to construct encryption schemes. However, because of the specificity of such tame automorphisms, it is important to evaluate the computational complexity of the tame decomposition problem for secure use of MPKC. In this paper, as the first step for security evaluations, we focus on Matsumoto-Imai cryptosystems. We shall prove that the Matsumoto-Imai central maps in three variables over F2 is tame, and we describe the tame decompositions of the Matsumoto-Imai central maps.

Original languageEnglish
Pages (from-to)221-228
Number of pages8
JournalAdvances in Mathematics of Communications
Issue number2
Publication statusPublished - May 2016


All Science Journal Classification (ASJC) codes

  • Algebra and Number Theory
  • Computer Networks and Communications
  • Discrete Mathematics and Combinatorics
  • Applied Mathematics

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