Problem statement: As distributed real-time multimedia services are accessed by users from different locations, the run-time performance must be managed and monitored to get a clear view of how media web services perform within their operational environments and to perform control actions to modify and adjust the their behavior. Otherwise it will provide negative effects on the reputation of se...

Francisco Javier Nieto, European Software Institute, Parque Tecnologico de Zamudio, E-48170 Zamudio-Bizkaia, Spain, [email protected] Leire Bastida, European Software Institute, Parque Tecnologico de Zamudio, E48170 Zamudio-Bizkaia, Spain, [email protected] Marisa Escalante, European Software Institute, Parque Tecnologico de Zamudio, E-48170 Zamudio-Bizkaia, Spain, marisa.escalante@esi....

This dissertation documents the creation of a test harness for OGSI grid services, as part of the DIGS project ongoing at NeSC.

When information services are organized to provide some composed functionality, their interactions can be formally represented as workflows. Traditionally, workflows are executed by centralized engines that invoke the necessary services and collect results. If services are clustered (e.g., based on geographic criteria), locally routing intermediary results between services in the same cluster c...

The problem of composing services to deliver integrated business solutions has been widely studied in the last years. Besides addressing functional requirements, services compositions should also provide agreed service levels. Our goal is to support model-based analysis of service compositions, with a focus on the assessment of non-functional quality attributes, namely performance and reliabili...

As Web services are increasingly accepted and used, the next step for them is the development of hierarchical and distributed services that can perform more complex tasks. In this paper, we focus on how to develop guarantees for the performance of an aggregate service based on the guarantees provided by the lower-level services. In particular, we demonstrate the problem with an example of an e-...

The ability to compose, on-demand, networked software services to meet evolving requirements is an important step towards the development of digital business ecosystems that allow participants realise novel business models. In this paper we address a crucial issue that must be addressed before dynamic service composition becomes commercially viable – how users can be charged for the use of such...

This thesis presents an approach to design, specify, validate, verify, implement, and evaluate composed web/grid services. Web and grid services can be composed to create new services with complex behaviours. The BPEL (Business Process Execution Language) standard was created to enable the orchestration of web services, but there have also been investigation of its use for grid services. BPEL s...

Service composition allows web services to be combined into new ones. Web service composition is increasingly common in mission-critical applications. It has therefore become important to verify the correctness of web service composition using formal methods. The composition of grid services is a similar but new goal. We have previously developed an abstract graphical notation called CRESS for ...

Composite web services are defined using the industry-standard language BPEL (Business Process Execution Logic). There is a strong need for graphical and automated support for this task. It is explained how CRESS (Chisel Representation Employing Systematic Specification) has been extended to meet this challenge. CRESS supports straightforward graphical descriptions of composite web services. Sa...