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.
|Number of pages||13|
|Journal||IEICE Transactions on Information and Systems|
|Publication status||Published - 2002 Feb|
- Card game
- Key exchange graph
- Key set protocol
- Secret key exchange