An improved multi-stage (t, n)-threshold secret sharing scheme

Abstract

Recently, Chang et al. proposed a multi-stage (t, n)-threshold secret sharing scheme based on the one-way function. For k secrets shared among n participants, each participant has to keep one secret shadow; but there are a total of kn public values. In this paper, a new multi-stage (t, n)-threshold secret sharing scheme was proposed, which is an alternative implementation of Chang et al.'s scheme. Each participant needs to keep only one secret shadow in sharing multiple secrets without updating each participant's secret shadow. For k secrets shared among n participants, there are only a total of k(n-t+1) public values. Analyses show that the proposed scheme is a computationally secure and efficient scheme. The implementation of the proposed scheme becomes very attractive, especially when the threshold value t is very close to the number of participants n. © Springer-Verlag Berlin Heidelberg 2005.