带时间特性的自动信任协商*

自动信任协商是陌生实体通过交替地披露属性证书建立信任关系的一种方法。现有的研究仅仅考虑与时间特性无关的其他方面，没有合理的信任协商会话调度方案，存在着拒绝服务攻击。提出了自动信任协商的基本组件，使用状态变换系统形式化描述了一个自动信任协商抽象模型。讨论了自动信任协商的时间特性，对原有安全策略扩展了时间约束安全策略，构造了一个带时间特性的自动信任协商状态变化系统。同时分析了安全策略的可满足性判定问题。

Timed automated trust negotiation

Automated trust negotiation is an approach to build trust relationship between strangers by disclosing attribute credentials alternately. However, the main work focuses on some aspects, which had nothing to do with the time character in recent research, without reasonable schedule scheme of ATN session and existing denial of service attack. This paper proposed the components of ATN and described an abstract ATN model with state-transition system. Extended the security policies so that it could describe the time character. Constructed a state-transition system with time character to simulate ATN. Discussed the satiability of security policies in ATN.