基于身份的门限密码体制

描述一个公钥密码体制,其中参与者的公钥是一个公开值,例如他的身份,这个体制由很多可信中心联合产生一个大合数N=pq,p,q为素数且p≡q≡3(mod 4),任意其中一个可信中心都不知道N的分解.另外,每一个可信中心拥有一个秘密指数的一个分享,这样产生一个门限解密.本文将讨论所提出的方案的安全性,并证明它与解决二次剩余问题的困难性有关.

An Identity Based Threshold Scheme

We describe a public-key system,in which the public key of a subseribe is a publicly known value,such as his indentity,in this sytem a number of a number of parties(trusted authorities) jointly generate a big modulus N=pq,where p,q are prime and p≡q≡3(mod 4),None of the parties know the factorization of N.In addition each party holds a share of the private exponent that enables threshold decryption.We discuss the security of the proposed scheme,and show that this is related to the difficulty of solving the quadratic residuosity problem.