摘要： 在设计阶段将Web服务组合可靠性指标约束分配到各组件服务,以提供一个可靠性高、成本最小化的Web服务组合是非常必要的。 为此,分析Web服务组合结构模式及其对应的可靠性。基于组件服务的可靠性和成本之间的关系函数,建立组合服务可靠性分配优化模型并利用遗传算法对其进行求解。使得在保证Web服务组合可靠性的前提下,将Web服务组合的可靠性指标合理分配给组件服务,并把成本控制到最低。实验结果表明,与其他可靠性分配方法相比,该方法在节约成本方面具有优越性,是有效且实用的,种群具有更好的收敛性。

关键词: Web服务组合, 服务质量, 可靠性分配, 成本, 优化模型, 遗传算法

Abstract: By allocating the reliability constraint of the Web service composition to each component service in the design phase,a service composition with high reliability and minimum cost can be provided.For this purpose,this paper analyzes structure patterns of service composition and corresponding reliability of these patterns are given.Then,it analyzes the reliability of the Web service composition.Based on the relationship between the reliability and the cost of the component services,it designs a reliability allocation optimization model to allocate reliability constraint to component services reasonably and uses genetic algorithm to solve it.The proposed optimization model can satisfy the reliability constraint of the service composition with minimum cost.Experimental results show that the proposed method is better than other reliability allocation method in terms of cost saving.It tests the effectiveness,practicality and efficiency of the method by extensive experiments.

Key words: Web service composition, Quality of Service(QoS), reliability allocation, cost, optimization model, Genetic Algorithm（GA）

中图分类号: 

• TP311