对一种公平非否认协议的新改进  

New Improvement on a Fair Non-repudiation Protocol

作　　者：雷新锋[1] 刘军[1] 肖军模[1] 

机构地区：[1]解放军理工大学通信工程学院,南京210007

出　　处：《计算机科学》2009年第8期94-97,148,共5页Computer Science

基　　金：江苏省自然科学基金(KB2008090)资助

摘　　要：Zhou-Gollmann协议是一种公平非否认协议,近年来得到广泛讨论。Kim发现该协议在时限公平性方面存在缺陷,针对该缺陷提出一种改进的协议,但其改进方法高度依赖于网络时钟的同步。通过详细分析,发现在缺乏时钟同步时Kim的改进协议也可导致不公平。针对此问题,提出一种新的改进方案。新的改进消除了协议对时钟同步的依赖性,保持了协议的公平非否认性,且不会降低协议的效率。Zhou-Gollmann protocol is a fair non-repudiation protocol which is widely discussed in recent years. Kim found a flaw of this protocol on time-limited fairness. Aimming at this flaw,Kim gave an improved protocol, but the improved schema highly depended on synchronization of network clock. We analyzed Kim ＇ s protocol in detail and show that, without clock synchronization, Kim＇s improved protocol is also unfair. Then we proposed a new schema to improve it further. Without reducing the efficiency of the original protocol, our new method avoids depending on synchronization of the clock, and keeps fairness and non-repudiation of the protocol.

关 键 词：公平性 非否认性 协议 时钟同步 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]