Replacement policies for service-based systems

Abstract

The need to change service-based systems during their execution time has been recognized as an important challenge in service oriented computing. There are several situations that may trigger changes in service-based systems such as unavailability or malfunctioning of services; changes in the functional, quality, or contextual characteristics of the services; changes in the context of the service-based system environment; emergence of new services; or changes in the requirements of the system. However, in order to support dynamic changes in service-based systems, it is necessary to have replacement policies describing what needs to be changed, and how and when the changes should be executed. In this paper, we describe replacement policies to support dynamic changes in service-based systems. These replacement policies are used in our service discovery framework that supports proactive identification of services in parallel to the execution of the system. A prototype tool has been implemented in order to illustrate and evaluate the framework. The results of some initial evaluation are also described in the paper. © 2010 Springer-Verlag.