Necessary and sufficient numbers of cards for sharing secret keys on hierarchical groups

Takaaki Mizuki, Takao Nishizeki

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)


Suppose that there are players in two hierarchical groups and a computationally unlimited eavesdropper. Using a random deal of cards, a player in the higher group wishes to send a one-bit message information-theoretically securely either to all the players in her group or to all the players in the two groups. This can be done by the so-called 2-level key set protocol. In this paper we give a necessary and sufficient condition for the 2-level key set protocol to succeed.

Original languageEnglish
Pages (from-to)333-345
Number of pages13
JournalIEICE Transactions on Information and Systems
Issue number2
Publication statusPublished - 2002 Feb


  • Card game
  • Key exchange graph
  • Key set protocol
  • Secret key exchange
  • Tree

ASJC Scopus subject areas

  • Software
  • Hardware and Architecture
  • Computer Vision and Pattern Recognition
  • Electrical and Electronic Engineering
  • Artificial Intelligence

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