Service Supervision Patterns: Reusable Adaption of Composite Services Masahiro Tanaka", Toru Ishida 1 ,2, Yohei Murakami 1 , and Donghui Lin! 1 Language Grid Project, National Institute of Information and Communications Technology (NICT) 3-5 Hikaridai, Seika-cho, Kyoto, Japan 2 Department of Social Informatics, Kyoto University Yoshida-Honmachi , Sakyo-ku , Kyoto , 606-8501 , Japan Abstract. A composite Web service provided as a "cloud" service should make its constituent Web services transparent to users. However, existing frameworks for composite Web services cannot realize such transparency because they lack capability of adapting changes of behaviors of con- stituents Web services and business rules of service providers . Service Supervision, proposed in the previous work, allows us to flexibly adapt a composite Web service by combining control execution functions which control behavior of running instances of composite Web services. How- ever, much flexibility of the execution control functions sometimes makes it difficult to design adaptation processes due to absence of accumulated know-how such as guidelines. Moreover, it often costs a lot to port adap- tation processes to the model of composite Web service to be adapted. To solve the problems , we first organized various adaptation processes based on some previous works. Then we proposed Service Supervision patterns, which consist of typical requirements for adaptation and WS- BPEL processes satisfying the requirements by using execution control functions . The patterns are easy for designers of composite Web services to understand and make it possible to reduce cost to port them to the model of a composite service. 1 Introduction In Cloud Computing, servers which provide Web services are transparent to users and users do not need to care numbers or locations of the servers. As for a composite Web service, which combines multiple Web services, the constituent Web services of the composite Web service should also be transparent to users when it is provided as a "cloud service". However, it is often difficult to realize the transparency because the constituent Web services can be provided by various service providers and the behaviors of the services can unexpectedly change. Therefore a composite Web service has to be capable of adapting to the changes. For example , there are still many services deployed outside cloud and through- put of the services may decline in an environment where too many requests can D.R. Avresky et al. (Eds.): Cloud comp 2009 , LNICST 34 , pp . 147-163, 2010 . © In stitut e for Computer Sci en ces , Social-Informati cs and Tele communications Engineering 2010