Abtract：

(1) Title:  Optimized Implementation of a General Secret Sharing (for audiences with security background)

Secret sharing is one of most popular cryptographic tools which has been proposed originally in 1979.  Shamir’s threshold secret sharing is the most popular scheme in the literature.  But, Shamir’s scheme has a special secret access structure in which (a) any t (i.e., the “threshold”) or more than t shareholders can recover the secret and (b) fewer than t shareholders cannot recover the secret.   A general secret sharing has more general secret access structure in which (a) any “qualified subset” of shareholders can recover the secret and (b) any “unqualified subset” of shareholders cannot recover the secret.  Most papers on general secret sharing in literature contain only theoretical discussion.  In this talk, I will introduce my recent paper to propose a complete implementation of a general secret sharing.  We use Boolean logic to characterize a general secret access structure and derive the minimal positive secret access and the maximal negative secret access subsets.  Then, we use these two subsets to determine parameters to implement a general secret sharing.  Our design enables to select optimized parameters and is a general design.