用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函...用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函数明确可以使用隐私数据的成员服务,简化隐私需求的同时,提高了隐私需求的通用性.为了验证服务组合是否满足用户隐私需求,首先通过隐私数据项依赖图(privacy data item dependency graph,简称PDIDG)描述组合中隐私数据项的依赖关系,然后采用隐私开放工作流网(privacy open workflow net,简称POWFN)构建隐私敏感的服务组合模型,通过需求验证算法验证服务组合是否满足用户隐私需求,从而能够有效防止用户隐私信息的非法直接暴露和间接暴露.最后,通过实例分析说明了该方法的有效性,并对算法性能进行了实验分析.展开更多
Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services ...Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services in the composition evolve due to changes in business needs. To address the deficiencies, the problem of adaptor reconfiguration is targeted in the context of service composition. Firstly, the formal models for describing services and adaptors are presented. Then, under this formalization,the notion of reconfiguration compliance is proposed to determine the validity of an adaptor instance with respect to its history executions and future executions. Based on the notion,the algorithm for reconfiguration analysis of adaptors is presented and it can be used for determining the migratability of an adaptor instance and the corresponding target state of reconfiguration if migratable.Finally,feasibility of the proposed approach is validated on a realistic case study. The proposed approach improves the flexibility of adaptor-based service composition by equipping adaptors with reconfiguration capabilities.展开更多
文摘形式化建模Web服务组合并分析其功能正确性和QoS可满足性,是提高组合服务可信性的重要手段,但目前形式化方法侧重功能正确性建模和分析,对QoS可满足性的建模和分析支持不足.为此提出一种时间概率代价进程代数TPPPA(Timed Probabilistic Priced Process Algebra),给出了TPPPA的语法和语义,并证明其具有功能、时间、概率和代价的统一建模和分析能力.用实例表明了TPPPA可有效支持Web服务组合功能正确性和QoS可满足性的形式化统一建模和分析.
文摘用户向Web服务组合提供隐私数据时,不同用户有自身的隐私信息暴露需求,服务组合应支持用户隐私需求的可满足性验证.首先提出一种面向服务组合的用户隐私需求规约方法,用户能够定义隐私数据及不同使用情境的敏感度,采用敏感度-信誉度函数明确可以使用隐私数据的成员服务,简化隐私需求的同时,提高了隐私需求的通用性.为了验证服务组合是否满足用户隐私需求,首先通过隐私数据项依赖图(privacy data item dependency graph,简称PDIDG)描述组合中隐私数据项的依赖关系,然后采用隐私开放工作流网(privacy open workflow net,简称POWFN)构建隐私敏感的服务组合模型,通过需求验证算法验证服务组合是否满足用户隐私需求,从而能够有效防止用户隐私信息的非法直接暴露和间接暴露.最后,通过实例分析说明了该方法的有效性,并对算法性能进行了实验分析.
基金National Natural Science Foundations of China(Nos.61272083,61262002,61170043)China Postdoctoral Science Foundation(Nos.20110491411,2014M562177)The Science Foundations of Nanjing Institute of Technology,China(Nos.QKJB201304,YKJ201420)
文摘Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services in the composition evolve due to changes in business needs. To address the deficiencies, the problem of adaptor reconfiguration is targeted in the context of service composition. Firstly, the formal models for describing services and adaptors are presented. Then, under this formalization,the notion of reconfiguration compliance is proposed to determine the validity of an adaptor instance with respect to its history executions and future executions. Based on the notion,the algorithm for reconfiguration analysis of adaptors is presented and it can be used for determining the migratability of an adaptor instance and the corresponding target state of reconfiguration if migratable.Finally,feasibility of the proposed approach is validated on a realistic case study. The proposed approach improves the flexibility of adaptor-based service composition by equipping adaptors with reconfiguration capabilities.