一种基于信任推理与演化的Web服务组合策略

为解决动态复杂互联网中恶意、欺诈、不诚信服务实体造成的服务组合质量不高的难题,文中基于开放网格服务体系架构(OGSA),建立了以公共信任演化系统和实体信任演化系统为主体构成的信任推理与演化系统；提出了受限于可信实体的信任演化、实体集合的信任演化、逐步逼近评价实体的信任演化等信任演化方法,以改变信任推理中的信任缺失与信任泛化的不足；通过服务实体间信任关系的推导、反演与递推,极大程度地丰富了实体的信任关系,以识别共谋欺骗并克服信任演化中直接信任关系稀小、前期信任匮乏的问题.文中以新的信任推理与演化为基础,提出了一种Web服务组合策略.应用实例及测试结果表明该服务组合策略能够有效地识别实体行为中潜在的风险,克服实体经验差异,较大幅度地提高了服务组合的成功率.

A Web Services Composition Strategy Based on Trust Reasoning and Evolution

To overcome the problem of poor quality of service caused by malice,fraud and dishonest service entities in dynamic and complex internet,the paper constructs a trust reasoning and evolution system.It is mainly composed of the public and entity trust evolution systems and based on the Open Grid Services Architecture(OGSA).This paper proposes a trust reasoning method to change the situation of trust missing and trust generalization,which constrained by the trusty entities,the entity set,successive approximation of evaluation entities,etc.The trust reasoning system could greatly enrich trust relationship among entities and distinguish conspiracy through deduction,inversion and recursion.It is capable of overcoming the problem aroused by the lack of direct trust and early stage trust in the traditional trust evolution.Therefore,it changes traditional methodology on trust relationship modeling.Based on the new trust reasoning and evolution method,we propose a Web service composition strategy.The practical example and testing results demonstrate the effectiveness of the new strategy on distinguishing potential risk in entity behavior,overcoming the problem of entity experience differences,and improving the success rate of services composition.