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We present courseware for UML/SysML modelling that supports collaborative learning at a distance. Learners can solve interactive modelling exercises and discuss their solutions. First evaluations show promising results.

Organisations wishing to engage in industrial collaborative networks will typically seek some guarantees concerning the reliability of their prospective partners before committing to cooperation. Evaluating reliability can encompass several aspects, but one of the most crucial things to consider from a cooperation perspective is whether the software systems that support the business processes of some collaborator actually behave as expected. For organisations that rely on a service-oriented computing infrastructure, this amounts to checking whether the functionality of the respective services is conformant to a given behavioural specification. Today’s state of the art lacks standardised methods for creating behavioural specifications of Web services, and also lacks tools for automating the process of behavioural conformance checking through testing. This paper presents a concrete method for creating formal specifications of Web service behaviour and utilising them within service registries for automated testing of service implementations in order to verify and certify their conformance.

Web services exposing run-time behaviour that deviates from their behavioural specifications represent a major threat to the sustainability of a service-oriented ecosystem. It is therefore critical to verify the behavioural conformance of services during run-time. This paper discusses a novel approach for run-time verification of Web services. It proposes the utilisation of Stream X-machines for constructing formal behavioural specifications of Web services which can be exploited for verifying that a service’s run-time behaviour does not deviate from what is defined in the specification. Our approach allows for checking both the control flow of a Web service and the values of the data in the generated responses. The paper also proposes a classification of Web services and discusses how different types of services can be verified at run-time. Finally, it presents a run-time monitoring and verification architecture and discusses how it can be integrated into different types of service-oriented infrastructures.

Recent years have seen the utilisation of Semantic Web Service descriptions for automating a wide range of service-related activities, with a primary focus on service discovery, composition, execution and mediation. An important area which so far has received less attention is service validation, whereby advertised services are proven to conform to required behavioural specifications. This paper proposes a method for validation of service-oriented systems through automated functional testing. The method leverages ontology-based and rule-based descriptions of service inputs, outputs, preconditions and effects (IOPE) for constructing a stateful EFSM specification. The specification is subsequently utilised for functional testing and validation using the proven Stream X-machine (SXM) testing methodology. Complete functional test sets are generated automatically at an abstract level and are then applied to concrete Web services, using test drivers created from the Web service descriptions. The testing method comes with completeness guarantees and provides a strong method for validating the behaviour of Web services.

Reliability and trust are fundamental prerequisites for the establishment of functional relationships among peers in a Collaborative Networked Organisation (CNO), especially in the context of Virtual Enterprises where economic benefits can be directly at stake. This paper presents a novel approach towards effective service discovery and selection that is no longer based on informal, ambiguous and potentially unreliable service descriptions, but on formal specifications that can be used to verify and certify the actual Web service implementations. We propose the use of Stream X-machines (SXMs) as a powerful modelling formalism for constructing the behavioural specification of a Web service, for performing verification through the generation of exhaustive test cases, and for performing validation through animation or model checking during service selection.