Cryptology ePrint Archive: Report 2016/929
A Generalized Ideal Secret Sharing Scheme
Abstract: Sharing a secret efficiently amongst a group of
participants is not easy since there is always an adversary /
eavesdropper trying to retrieve the secret. In secret sharing
schemes, every participant is given a unique share. When the
desired group of participants come together and provide their
shares, the secret is obtained. For other combinations of shares,
a garbage value is returned. A threshold secret sharing scheme
was proposed by Shamir and Blakeley independently. In this
(n,t) threshold secret sharing scheme, the secret can be obtained
when at least t out of n participants contribute their shares.
This paper proposes a novel algorithm to reveal the secret only
to the subsets of participants belonging to the access structure.
This scheme implements totally generalized ideal secret sharing.
Unlike threshold secret sharing schemes, this scheme reveals
the secret only to the authorized sets of participants, not any
arbitrary set of users with cardinality more than or equal to t.
Since any access structure can be realized with this scheme, this
scheme can be exploited to implement various access priorities
and access control mechanisms. A major advantage of this
scheme over the existing ones is that the shares being distributed
to the participants is totally independent of the secret being
shared. Hence, no restrictions are imposed on the scheme and it
finds a wider use in real world applications.
Category / Keywords: foundations / Generalized Secret Sharing, Access Structures
Date: received 26 Sep 2016
Contact author: tanujay saha at gmail com
Available format(s): PDF | BibTeX Citation
Version: 20160927:212306 (All versions of this report)
Short URL: ia.cr/2016/929
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