A SLA-Oriented Management of Containers for Hosting Stateful Web Services

Service-oriented architectures provide integration of interoperability for independent and loosely coupled services. Web services and the associated new standards such as WSRF are frequently used to realise such service-oriented architectures. In such systems, autonomic principles of self-configuration, self-optimisation, self-healing and self- adapting are desirable to ease management and improve robustness. In this paper we focus on the extension of the self management and autonomic behaviour of a WSRF container connected by a structured P2P overlay network to monitor and rectify its QoS to satisfy its SIAs. The SLA plays an important role during two distinct phases in the life-cycle of a WSRF container. Firstly during service deployment when services are assigned to containers in such a way as to minimise the threat of SLA violations, and secondly during maintenance when violations are detected and services are migrated to other containers to preserve QoS. In addition, as the architecture has been designed and built using standardised modern technologies and with high levels of transparency, conventional Web services can be deployed with the addition of a SLA specification.