实用的前向安全门限重签名方案

Practical Forward Security Threshold Multi-signature Scheme

就目前已有的前向安全门限数字签名存在理论错误的缺陷,提出一种新的实用的前向安全门限重数字签名方案。为降低门限签名者密钥泄漏造成的损失,将群组成员密钥按时间段进行更新,群组公钥保持不变。即使第k时间段的签名密钥被泄露,攻击者无法伪造第k时间段之前的签名,使签名密钥被泄露所造成的损失降到最小。基于强RSA的假设,证明方案可抵抗非法签名者的伪造攻击和具有前向安全性和实用性。

With the presence of the theory defects and unpractice, a new practical forward-secure threshold multi-digital signature scheme was proposed. Keys of members of the group are updated as time goes periodically , and the corresponding public key remains the same throughout the effective period of time. Even if the k-time stage signature key is compromised, any attackers can not launch the forward signing key of k - 1 time stage, They can not forge signature before the k - 1 time stage. It can make the loss to a minimum even if his signature key is com- promised. The scheme is proved unforgery, forword security and pratice.