Security of Improved Identity-based Conference Key Distribution Systems

  • Kenji Koyama
  • Kazuo Ohta
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 330)


At Crypto-87 conference, we proposed identity-based key distribution systems for generating a common secret conference key for two or more users. Protocols were shown for three configurations: a ring, a complete graph, and a star. Yacobi has made an impersonation attack on the protocols for the complete graph and star networks. This paper proposes improved identity-based key distribution protocols to counter his attack.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1988

Authors and Affiliations

  • Kenji Koyama
    • 1
  • Kazuo Ohta
    • 2
  1. 1.Basic Research LaboratoriesNippon Telegraph and Telephone CorporationMusashino-shi, TokyoJapan
  2. 2.Communications and Information Processing LaboratoriesNippon Telegraph and Telephone CorporationYokosuka-shi, KanagawaJapan

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