Abstract: To judge whether the atomic service and its Quality of Service (QoS) in composite service affected the fully realization of customers value proposition,the value analysis of composite Web service was researched.The value proposition and measurement method for composition Web services based on state-transition were presented.The function and QoS provided by composition service were regarded as the constraints of value proposition,and the corresponding value decision methods were researched,as well as the analysis methods of responsibility point,Degree of Criticality (DoC) and Degree of Sensitivity (DoS) for each atomic Web service (and its QoS parameters) were proposed,which was aimed at finding the defects hindered the fully implementation of value propositions and providing foundations for the future optimization of composite Web services.A case study was inducted to valid the effectiveness of the proposed method.

Key words: composite Web service, service value, value proposition, state transition, value analysis

摘要： 为评判组合服务中包含的原子服务及其QoS是否妨碍客户期望价值的充分实现,从而为后续组合服务的优化提供依据,研究组合Web服务的价值分析方法。提出基于状态转换的组合服务价值表述和度量方法,将组合服务所能提供的功能和能够达到的服务质量作为价值期望的约束条件,进而研究价值可满足性的判定方法,提出影响价值实现程度的责任点、关键度、敏感度分析方法,目标是找到妨碍价值充分实现的原子服务及其服务质量,为后续组合Web服务的优化提供依据。通过案例验证了所提方法的有效性。

关键词: 组合Web服务, 服务价值, 价值期望, 状态转换, 价值分析