Two-Stage Adaptation for Dependable Service-Oriented System

The development of Service-Oriented Systems has gained a considerable momentum as a means for building distributed applications and business processes. It emphasizes the loosely coupled construction of services from independent providers over the network. As a consequence, the dependability of such systems strongly depends on their ability to self-adapt to changes in its execution environment, such as unreachable component services, or changed delivered QoS. In this paper, we propose a two-stage approach to realize a self-adaptive SOA system, aimed at the fulfillment of dependability requirements. Specifically, we divide the adaptation process into two stages, proactive adaptation and reactive adaptation, to implement self-protecting and self-healing respectively, and provide a methodology driving the system adaptation. To bring this approach to fruition, a prototype system A-ServiceMix is developed by extending Apache ServiceMix.