Consistency of service composition

We address the problem of ensuring that, when an application executing a service binds to a service that matches required functional properties, both the application and the service can work together, i.e., their composition is consistent. Our approach is based on a component algebra for service-oriented computing in which the configurations of applications and of services are modelled as asynchronous relational nets typed with logical interfaces. The techniques that we propose allow for the consistency of composition to be guaranteed based on properties of service orchestrations (implementations) and interfaces that can be checked at design time, which is essential for supporting the levels of dynamicity required by run-time service binding. © 2012 Springer-Verlag Berlin Heidelberg

Aggregation and Adaptation of Web Services

Service-oriented computing highly supports the development of future business applications through the use of (Web) services. Two main challenges for Web services are the aggregation of services into new (complex) business applications, and the adaptation of services presenting various types of interaction mismatches. The ultimate objective of this thesis is to define a methodology for the semi-automated aggregation and adaptation of Web services capable of suitably overcoming semantic and behaviour mismatches in view of business process integration within and across organisational boundaries. We tackle the aggregation and adaptation of services described by service contracts, which consist of signature (WSDL), ontology information (OWL), and behaviour specification (YAWL). We first describe an aggregation technique that automatically generates contracts of composite services satisfying (behavioural) client requests from a registry of service contracts. Further on, we present a behaviour-aware adaptation technique that supports the customisation of services to fulfil client requests. The adaptation technique can be used to adapt the behaviour of services to satisfy both functional and behavioural requests. In order to support the generation of service contracts from real-world service descriptions, we also introduce a pattern-based compositional translator for the automated generation of YAWL workflows from BPEL business processes. In this way, we pave the way for the formal analysis, aggregation, and adaptation of BPEL processes

Process Oriented Discovery of Business Partners

Emerging technologies and industrial standards in the field of Web services enable a much faster and easier cooperation of distributed partners. With the increasing number of enterprises that offer specific functionality in terms of Web services, discovery of matching partners becomes a serious issue. At the moment, discovery of Web services generally is based on meta-information (e. g. name, business category) and some technical aspects (e. g. interface, protocols). But, this selection might be to coarse grained for dynamic application integration, and there is much more information available. This paper describes a method to discover business partners based on the comparison of their behavior -- specified in terms of their published Web service process models