基于概率时间自动机Web服务质量的形式化建模分析  

Formal Modeling Analysis of Web QoS Based on PTA

作　　者：陆闯[1] 刘淑芬[1] 王晓燕[1] 

机构地区：[1]吉林大学计算机科学与技术学院,长春130012

出　　处：《吉林大学学报（理学版）》2015年第3期531-537,共7页Journal of Jilin University:Science Edition

基　　金：国家自然科学基金(批准号:60973041);国家高技术研究发展计划863项目基金(批准号:2009AA010314);吉林省科技发展计划项目(批准号:20115007)

摘　　要：针对拓展的Web服务体系结构,利用概率时间自动机(probabilistic timed automata,PTA)对Web服务组合进行形式化建模,将Web服务组合的过程理解为一个实时系统的运行过程,进而对Web服务组合的整体服务质量(quality of service,QoS)进行定量分析,从而克服了已有Web服务质量研究方式主要集中在对单个Web服务分析评估上的局限性,在整个分析过程中充分考虑Web服务组合执行过程所具有的随机性和不确定性,具有较高的可信度.通过实验说明了建模分析方法的可行性,并证明了采取相应的服务选择策略有助于提高Web服务组合的成功率.In view of the extended Web service architecture, we formally modeled the Web service composition with probabilistic timed automata （PTA）. The process of Web service composition was understood as a real-time system operation process. We then overcame the limitation of existing research approach of Web service quality which focused the service quality on a single Web service, by quantitatively analyze the quality of Web service composition on the basis of the model we built before. The stochastic and nondeterministic characteristics in the execution of Web service composition were fully taken into account in the whole analysis so as to make the result credible. Finally, an example was given to illustrate the feasibility of the modeling analysis method, proving that the corresponding service selection strategy can improve the success probability of Web service composition.

关 键 词：WEB服务组合 概率时间自动机 定量建模分析 WEB服务质量 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]