Abstract: Based on Shamir’s threshold scheme and the elliptic curve cryptosystem，a multi-stage secret sharing scheme among multiple organizations is proposed，which owns the advantage of a secret sharing scheme on access structure and the feature that the sharing secret can be restored in order in a multi-stage secret sharing scheme.Each participant and the dealer can communicate with each other in the form of plaintext.In the recovery phase，anybody is allowed to check whether a participant provides the true shadow or not from the public information.The security of the scheme is based on the security of the Shamir’s threshold scheme and the difficulty of computing elliptic curve discrete logarithm problem.

Key words: elliptic curve cryptosystem, multi-stage secret sharing, access structure, threshold scheme

摘要： 基于Shamir门限方案和椭圆曲线密码体制，提出了一个多组织间的多级秘密共享方案。方案同时具有一般接入结构上秘密共享方案的优点和多级秘密共享方案中秘密按顺序恢复的特点。方案执行过程中各参与者与秘密分发者之间可以明文的形式进行通信。在秘密恢复阶段，任何人都可以通过公开信息验证参与者是否进行了欺诈。方案的安全性基于Shamir门限方案的安全性和有限域上椭圆曲线离散对数问题的难解性。

关键词: 椭圆曲线密码体制, 多级秘密共享, 接入结构, 门限方案