一个自授权系统及问题的知识复杂性

One Self delegation Scheme and the Knowledge Complexity of Problems

基于图同构零知识证明的标识－鉴别－签名系统，提出了一个解决自授权问题的方法．与以前的方法相比，虽然两者都是基于对主秘密的逐步暴露来实现的，但前者是基于图同构置换来实现的，而后者是基于类似于秘密共享的思想来实现的．在研究给出的自授权系统的安全性时，定义了问题级的知识复杂性、实际知识复杂性和计算知识复杂性．应把它们作为协议知识复杂性的上界．

A solution to the problem of self delegation using the identification authentication signature scheme based on the graph isomorphism problem is proposed in this paper. The major difference from the traditional solutions is that it is based on the graph isomorphism rather than computing numeric theory problem, though they all leak out secret information little by little. The knowledge complexity of problems, the including knowledge complexity, the practical knowledge complexity, and the computing knowledge complexity are also defined. In the authors' opinion, these definitions should be used as the upper bound of knowledge complexity of protocols.