Web service selection for transactional composition

A Web Service is a self-describing, self-contained modular application that can be published, located, and invoked over a network, e.g. the Internet. Web Services composition provides a way to obtain value-added services by combining several Web Services. The composition of Web Services is, therefore, suitable to support enterprise application integration. WS-CDL (Web Services Choreography Description Language) is a W3C candidate recommendation for the description of peer-to-peer collaborations for the participants in a Web Services composition. In this paper we focus our attention on the development of a methodology for the design and validation of composite Web Services using WS-CDL as the language for describing Web Services interactions and Petri nets as a formalism that allows us to simulate and validate the described systems. We specifically intend, then, to capture timed and prioritized collaborations in composite Web Services, so the model of Petri nets that we use is a prio...

International Journal of Computer and Electrical Engineering, 2014

Web services technology provides a platform on which we can develop distributed services. The interoperability among these services is achieved by various standard protocols. In recent years, several researches suggested that Petri Nets provide a satisfactory assistance to the whole process of web services development. Business transactions, on the other hand, involve the coordination and interaction between multiple partners. With the emergence of web services, business transactions are conducted using these services. The coordination among the business processes is crucial, so is the handling of faults that can arise at any stage of a transaction. BPEL models the behavior of business process interaction by providing a XML based grammar to describe the control logic required to coordinate the web services participating in a process flow. However BPEL lacks a proper formal description where the composition of business processes cannot be formally verified. Petri Nets, on the other hand, facilitates a formal foundation for rigorous verification of the composition. This paper presents a comparison of web service composition between BPEL and Petri nets.

2006

Current Web services composition approaches do not take into account transactional requirements defined by designers. The transactional challenges raised by the composition of Web services are twofold: relaxed atomicity and dynamicity. In this paper, we propose a new process to automate the design of transactional composite Web services. Our solution enables the composition of Web services not only according to functional requirements but also to transactional ones defined using the Acceptable Termination States model. The resulting composite Web service is compliant with the consistency requirements expressed by designers and its execution can easily be coordinated using the coordination rules provided as an outcome of our approach.

2006 IEEE International Conference on Web Services (ICWS'06), 2006

Current Web services composition approaches do not take into account transactional requirements defined by designers. The transactional challenges raised by the composition of Web services are twofold: relaxed atomicity and dynamicity. In this paper, we propose a new process to automate the design of transactional composite Web services. Our solution enables the composition of Web services not only according to functional requirements but also to transactional ones defined using the Acceptable Termination States model. The resulting composite Web service is compliant with the consistency requirements expressed by designers and its execution can easily be coordinated using the coordination rules provided as an outcome of our approach.

Nowadays, with the emergence and the evolution of new technologies, such as e-business, a large number of companies are connected to Internet, and have proposed web services to trade. Web services as presented, are conceptually limited components to relatively simple functionalities. Generally, a single service does not satisfy the users needs that are more and more complex. Therefore, services must be made able to be composed to offer added value services. In this paper, a web services composition approach, modelled by Objects-Oriented Petri nets, is presented. In his context, an expressive algebra, which successfully solves the web services complex composition problem, is proposed. A java tool that allows automating this approach; based on a definite algebra and a G-nets meta-model, proposed by us, is developed.

Formal Techniques for …, 2005

Abstract. We address the problem of composing Web Services in long-running transactional business processes, where compensations must be dealt with ap-propriately. The framework presented in this paper is a Java API called Java Transactional Web Services (JTWS), ...

International Journal of Cooperative Information Systems, 2014

Web service composition, that recursively constructs a composite web service out of the existing services based on a business workflow has been acknowledged as a promising approach to meet the user demands, whenever a single service alone cannot fulfil the needs. In view of frequent failures in the internet environment where the composed service is executed, reliability of the composed service must be ensured. The reliability is determined by the behavioral or transactional properties of component services. The component services for each activity of the workflow must be selected based on their behavior so that their execution results in a consistent termination. Service selection must happen at run-time in order to consider the services available in a service registry at the time of execution. Towards this need, a dynamic transaction aware web service selection approach is proposed in this paper. Further, whenever user requirements change, a long running transaction must be interru...

Science of Computer Programming, 2012

A Web Service is a self-describing, self-contained modular application that can be published, located, and invoked over a network, such as the Internet. Web Service composition provides a way to obtain value-added services by combining different existing facilities, which are then able to support the integration of commercial applications. WS-CDL (Web Services Choreography Description Language) is a W3C candidate recommendation for the description of peer-to-peer collaborations by participants in a Web Services composition. This paper focuses on several important aspects of WS-CDL, namely, data variables, timed restrictions, as well as the priorization of collaborations. In WS-CDL there are no priorities, thus, one of our first goals is to provide a WS-CDL definition of prioritized collaborations. We also define a semantics of WS-CDL (with priorities) by means of prioritized-timed colored Petri nets.

A Web Service is a component written in any language, deployed on any platform, which has a standard wrapping layer based on XML.The component can interact with other applications which themselves comply with the Web Services standards. Generally, a single service does not satisfy the users needs that are more and more complex. Therefore, services must be made able to becomposed to build new value added services. This process is called Web services Composition. This latter is a critical subject that requires formal techniques for its completion. In this paper, we show how basic and existent services can be composed to create a composite service which offers a new functionality. In this context, we propose an expressive Labeled generalized stochastic Petri net based algebra that succeeds in the complex Web services composition. Basic and advanced constructs which are supported by the proposed algebra are syntactically and semantically defined.

Automatic composition of Web services is a challenging task as independently developed Web services are not always compatible with each other. In order to resolve the heterogeneity between Web services and improve the quality of Web service composition, we propose a new approach based on semantics for Web service composition, which widely deploys Petri Nets and ontology. This paper proposes a framework for semantic Web service composition that builds Petri net model of interactions between Web services and builds ontology representing domain knowledge, then combines the Petri net models with ontology-based mediation.