一种新的多方不可否认协议

首次指出不可否认协议运行结果可分为认证强公平和期望强公平,其中后者优于前者。利用GPS数字签,提出一个新的带离线可信第三方的多方不可否认协议,该协议实现了期望强公平且允许发方给不同的接收方同的消息,突破了先前协议只允许发方给不同的接收方发送同一消息的局限性。协议同时允许发方自由选择,使得交易灵活而符合实际。最后给出协议的安全性分析。

A New Multi-party Non-repudiation Protocol

Expected strong fairness and certified strong fairness, two executie results of non-repudiation protocols, are firstly introduced, and the former is superior to the later. Based on the GPS digital signature scheme and a group encry ption scheme, a new multi-party non-repudiation protocol with an off-line trusted third party is presented. The presented protocol provides"expected strong fairness", and allows one sender to send different messages to multiple different recipients, eliminates the previous restriction on the exchange of the"same message". The sender can barter with any recipients at his will and it makes the protocol more practical. The security analysis are given finally.