Nonperfect Secret Sharing Schemes

: Nonperfect secret sharing schemes NSSs have an advantage such that the size of shares can be shorter than that of perfect secret sharing schemes. This paper shows some basic properties of general NSS. First, we present a necessary and su cient condition on the existence of an NSS. Next, we show two bounds of the size of shares, a combinatorial type bound and an entropy type bound. Further, we de ne a compact NSS as an NSS which meets the equalities of both our bounds. Then we show that a compact NSS has some special access hierarchy and it is closely related to a matroid. Veri able nonperfect secret sharing schemes are also presented. Key Words: secret sharing scheme, nonperfect Category: E.3 Data encryption

• Type: Conference
• Year: 1992
• Where: ASIACRYPT
• Authors: Wakaha Ogata, Kaoru Kurosawa, Shigeo Tsujii
• Keywords: ASIACRYPT 1992, Compact Nss, Cryptology, Nonperfect Secret Sharing, Secret Sharing Scheme