Service composition aims at achieving a business goal by composing existing service-based applications or components. The response time of a service is crucial, especially in time-critical business environments, which is often stated as a clause in service-level agreements between service providers and service users. To meet the guaranteed response time requirement of a composite service, it is important to select a feasible set of component services such that their response time will collectively satisfy the response time requirement of the composite service. In this work, we use the BPEL modeling language that aims at specifying Web services. We extend it with timing parameters and equip it with a formal semantics. Then, we propose a fully automated approach to synthesize the response time requirement of component services modeled using BPEL, in the form of a constraint on the local response times. The synthesized requirement will guarantee the satisfaction of the global response time requirement, statically or dynamically. We implemented our work into a tool, Selamat and performed several experiments to evaluate the validity of our approach.

中文翻译：

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自动合成服务组合的本地时间要求

服务组合旨在通过组合现有的基于服务的应用程序或组件来实现业务目标。服务的响应时间至关重要，尤其是在时间紧迫的业务环境中，通常在服务提供者和服务用户之间的服务级别协议中将其表示为条款。为了满足组合服务的保证响应时间要求，重要的是选择一组可行的组件服务，以使它们的响应时间共同满足组合服务的响应时间要求。在这项工作中，我们使用旨在指定Web服务的BPEL建模语言。我们使用定时参数对其进行扩展，并为其配备形式语义。然后，我们提出了一种全自动方法来综合使用BPEL建模的组件服务的响应时间要求，以限制本地响应时间的形式。综合要求将保证静态或动态满足全局响应时间要求。我们将工作落实到一个工具中，Selamat并进行了一些实验，以评估我们方法的有效性。