基于模板的服务选择方法

Method of Web Service Selection Based on Template

在Web环境中,服务是千变万化的,满足相同功能的服务可能会有多个,这些服务具有不同的QoS参数,如何从中选择满足模板中各服务节点功能需求的具体服务,形成一个可执行的组合服务流程来完成用户的需求,成为服务组合中的一个关键问题。在基于模板的服务组合基础之上,提出一种解决模板选择和服务选择过程中的QoS最优化问题的模型,建立模板QoS模型,保证最大概率选择到QoS最优模板。在模板的节点选择服务过程中基于改进多目标遗传算法,同时优化多个QoS参数,最终产生一组满足约束条件的QoS最优服务组合流程集。实验结果表明了算法具有良好的可行性和有效性。

Services are protean in Web environment. There may be several services which provide the same function, and those services have different quality of service. Selecting a service instance for each service node of the template with optimal QoS under the condition of satisfying the global QoS constraints,is the key of service composition. Based on composition template,proposed a model to solve the problem of QoS global optimal in the process of template selection and service selection. Build the model of template QoS to maximize the probability to select optimal QoS template. The problem of service selection with QoS global optimal is transformed into a multi-objective services composition with QoS constraints. Produce a set of optimal services composition process with constraint principle by means of optimizing various QoS parameters simultaneously. Experimental results show the feasibility and efficiency of this method.