A Proactive Secret Sharing Scheme in matrix projection method

Abstract

Proactive Secret Sharing (PSS) scheme is a method to periodically renew n secret shares in a (k, n) threshold-based Secret Sharing Scheme (SSS) without modifying the secret, or reconstructing the secret to reproduce new shares. Traditionally, PSS schemes are developed for the Shamir's SSS which is a single SSS. Bai (2006) developed a multiple-secret sharing scheme using matrix projection. This paper presents a distributed PSS method for the matrix projection SSS. Once the new shares are updated, adversaries cannot discover the secrets from k shares which are mixed with past and present shares.