Non-intrusive QoS monitoring and analysis for self-healing web services

Monitoring and analysis of QoS are crucial steps for the provisioning of self-healing Web services and for managing web service-based distributed interactive applications. Dealing with these issues becomes even more challenging when applications are dynamically built by composition of distributed services involving different service providers. In this case, assuming access to the internal logic and its implementation within the composed Web services is not realistic. In this paper, we propose an architectural framework for monitoring and analysis of QoS driven by models for QoS analysis. This framework has been implemented and experimented for the web service technology within the European WS-DIAMOND project. We consider the general context where only SOAP messages between web services are monitored. The main novelty of our approach is, on the one hand, to provide a generic application-independent framework. On the other hand, we provide models allowing QoS deficiencies to be detected and considered as an indicator of the health degradation of the monitored Web services.