基于QoS的可信Web服务组合研究

如何合理、高效地选择和组合众多功能相似的服务，为用户提供更优质的服务，是当前SOA领域研究的重点和难点。服务质量QoS(Quafity of Service)的引入，在一定程度上保证了服务组合的合理性，但对于如何确保服务组合的可信，目前还没有一个比较完善和可行的方案。因此，提出了可信Web服务组合模型(Trust Web Service Composition Modcl,TWSCM)，并通过在原有Wcb服务体系架构上增加QoS代理和可信模块来确保服务组合的质量和可信。最后，在语言网格上进行了相关实验，结果表明，该方法能为用户提供高质量、可信的组合服务，从而验证了该方法的合理性和有效性。

Trustworthy Web Service Composition Approach Based on QoS

How to select and combine the services from available ones with similar functions appropriately and efficient1y to provide much better services for users is an important yet difficult issue in SOA. The rationality of service composition is improved to a certain extent with the introduction of Quality of Service(QoS). However, there is still no effident way to ensure the trustworthiness of the service composition. With such an observation in mind, a Trust Web Service Composition Modcl(hWSCM) was proposed to enhance the trustworthiness of service composition. hhis was achieved by adding QoS agents and trust control module to existing typical Web service composition models. Finally, experiments were conducted on the Language Grid (http://langrid. nict.go. jp). The experimental results show that the proposed approach can provide trustworthy composite services with high quality.