Quality of Service Management in Service Oriented Architectures
Gaetano Francesco Anastasi · 2011
The concept of Service Oriented Architectures (SOAs) has gained momentum in Information and Communication Technology (ICT) application area in recent years, introducing an innovative approach to the analysis, design and development. Many applications provided as services are time-critical and demand soft real-time requirements that must be taken into account for providing a certain Quality of Service (QoS) to service consumers. Moreover, in the context of SOAs there is an increasing interest in enriching Service Level Agreements (SLAs) established between providers and consumers with attributes as quantifiable QoS parameters, that the provider must respect for avoiding to incur in penalties. For providing strong guarantees, SOAs must be enhanced with an advanced execution management that takes into consideration the underlying resources used for service provisioning. Management in the SOA context is not only about managing the services, but also about managing the network, the computing units and various other resources, that could be also virtualized in the case of cost-effectively large-scale systems. In this dissertation, this problem will be generically indicated with the term QoS management and will be addressed with a particular focus on service-oriented real-time applications. By using proper resource management techniques borrowed from the real-time system theory, it will be shown that the service provider can guarantee the QoS negotiated by consumers, in the context of QoS-enabled SOAs. In particular, a generic service-oriented QoS architecture has been designed and developed for negotiating and providing services with soft real-time guarantees. Also, many realistic experiments have been conducted in Linux testbeds for showing the effectiveness of the proposed approach in different ICT environments, like industrial automation platforms, virtualized infrastructures and Wireless Sensors Networks.