Multi-Use Multi-Secret Sharing Scheme for General Access Structure

TL;DR

This paper presents a flexible, efficient multi-secret sharing scheme for general access structures that allows dynamic updates and includes verification features, using hash functions and Lagrange interpolation.

Contribution

It introduces a multi-use, multi-secret sharing scheme that supports dynamic access structure modifications without changing existing shares, enhancing flexibility and security.

Findings

Supports dynamic addition and removal of secrets and participants

Ensures verification of information between participants and combiner

Maintains efficiency with only one share per participant

Abstract

The main aim of this paper is to construct a multi-secret sharing scheme for general access structure in a trusted dealer model using suitable hash function and Lagrange's interpolation method. Even though, the proposed scheme is a multi-secret and multi-use one, each participant has to carry only one share. The suitable use of collision resistant one way hash function makes the scheme efficient and multi-use. Moreover, the scheme has a nice property that secrets, participants or qualified sets of participants may be added to or even may be made inactive dynamically by the dealer to get a new access structure without altering the shares of the existing participants in the old access structure. Finally, in the proposed scheme, both the combiner and the share holders can verify the correctness of the information that they are receiving from each other.