一种面向群体的密码系统改进方案

利用自证明公钥技术,Saeednia和Ghodosi提出了一种面向群体的(t,n)密码系统(S-G系统)。但是,这种系统无法阻止群体中的两个合法参与者进行同谋攻击。为此,Ghodosi和Saeednia提出了一种改进的系统(G-S系统)。然而,这种改进系统仍然有缺陷。本文提出了一种新的改进系统,在不增加系统的运算量和通信量的情况下有效地抵御了同谋攻击,同时还简化了系统的某些执行过程。

A modified group-oriented cryptosystem

With self-certified public key cryptographic approach,Saeednia and Ghodosi presented a group-oriented(t,n)cryptosystem(S-G cryptosystem).However,this cryptosystem cannot withstand conspiracy attacks.Therefore,Ghodosi and Saeednia proposed a modified version for the cryptostem.But,in fact,there are some security flaws in that improved cryptosystem.In this paper,a novel modified cryptosystem is presented for the S-G cryptosystem.This new cryptosystem has an easy implementation with an ideal overhead of computation and communication.