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In this work we give a formal background and identify the limits of applicability of local matching criteria (among which the well-known Zaremski and Wings΄s plugin-match) when they are used to automatically retrieve all the capabilities that are necessary to instantiate a given choreography. In doing this it is necessary to take into account and somehow merge two possibly conflicting perspectives: the local criterion for selecting single capabilities and the overall goal that we mean the composition to pursue. Formally, the problem is interpreted as the study of the preservation of the global properties of a choreography, when its roles are played by specific services. [ABSTRACT FROM AUTHOR]

The Business Process Modeling Notation (BPMN) and the Business Process Execution Language (BPEL) are the de-facto standards for process modeling and implementation. While BPMN allows to define choreographies, i.e. the interaction behavior of interconnected services, BPEL only allows an endpoint-centric view on services. To achieve applicability of BPEL in the choreography space, we defined BPEL4Chor as choreography extensions for BPEL in previous work. This paper extends on this work and makes a contribution for the model-driven development of service-based systems in inter-organizational settings: It extends BPMN for enabling the generation of fully defined BPEL4Chor choreographies and presents how to carry out this transformation. [ABSTRACT FROM AUTHOR]

There are two types of behavioural model in the WSMO semantic description of services: an orchestration and a choreography, together called the interface. While an orchestration defines a service's behaviour as a composition of existing parts, a choreography is intended to document the conversation of messages exchanged with a single client. In this paper we present a three-level model for behavioural descriptions, and how the Cashew workflow model fits into this, building on existing work in, and establishing connections with, semantic web services, workflow, and software engineering design. [ABSTRACT FROM AUTHOR]

While web service technology is becoming a de facto standard for integration of business applications, it is also rapidly emerging as an effective means for achieving inter-operability among the devices in network centric ubiquitous systems. When such a web service enabled device engages in a conversation with a service provider, it becomes necessary to define an interaction logic required between them. For this purpose, one can use a choreography language to specify the rules of engagement between the device and the web service provider. This paper presents a framework for automatically synthesizing conversation protocols from a choreography description defined in WS-CDL. The proposed framework adopts WSCL as a conversation protocol language, and defines a set of rules that can be used to effectively transform a WS-CDL specification into WSCL documents for collaborating peers. It is expected that the work presented in this paper can enhance the interoperability between web service-based processes in ubiquitous systems through automating the process of extracting conversation protocols from a choreography definition. [ABSTRACT FROM AUTHOR]

Languages for web services choreography are becoming more and more important for B2B integration. However, the development of web services-based systems is complex and time-consuming. Enterprises have to agree on collaborative business processes and then derive their respective web services choreographies in order to implement B2B collaboration. To support it, this paper presents a MDA approach for collaborative processes. We describe the components and techniques of this approach. We show how collaborative process models defined with the UP-ColBPIP language can be used as the main development artifact in order to derive choreography specifications based on WS-CDL. The transformations to be carried out are also discussed. The main advantage of this MDA approach is that it guarantees that the generated web services choreographies fulfill the collaborative processes agreed between the partners in a business level. [ABSTRACT FROM AUTHOR]

The modelling of B2B scenarios focuses on conversations between key partners to establish a common business context for their collaboration. With the prevalence of Web services, attention has turned to service choreographies as a means of message exchange ordering between collaborating participants, from a global (or shared) understanding. As such, the message ordering in a choreography model can then be used to determine the message ordering behaviour of each participant΄s process. In this paper, we extend the suitability of choreography modelling for the early phase of analysis, where the participants and the nature of interactions develops under the flux of requirements acquisition. In particular, we develop a structural view of interactions and stepwise refinement, leading to behavioural considerations, reminiscent of classical techniques. In addition, we introduce contextualisation of intent behind message exchanges in the form of speech acts. This, we show, can be used to automatically detect conflicts in conversations, in the business sense, namely negotiation or provision breakdowns - prior to technical implementations of choreographies. Model abstraction and refinement is based on Semantic Object Model (SOM), and a mapping to the Business Process Modelling Notation (BPMN) is shown. [ABSTRACT FROM AUTHOR]

We propose a new conceptual model for choreographies of web-services. Choreographies are seen as virtual workflow models shared among participants. Subsets of these participants might have more refined models known only to them. So we see choreographies actually as federations of process models (choreographies as well as orchestrations). In this paper we discuss this layered concept, and present a metamodel with the following distinguishing features: It is fully distributed and does not require a central or global authority. It captures the control flow and the data flow aspects of the processes. Choreography models can be (re)used in several other choreographies. Additionally, we provide a procedure which checks whether choreographies fit together, i.e. the conformance of the federation relationship between models. [ABSTRACT FROM AUTHOR]

[Context and motivation] Choreographies are a form of service composition in which partner services interact in a global scenario without a single point of control. The absence of an explicitly specified orchestration requires changes to requirements practices to recognize the need to optimize software services choreography and monitoring for satisfaction with system requirements. [Question/problem] We developed a requirements-led approach that aims to provide tools and processes to transform requirements expressed on service-based systems to QoS-aware choreography specifications. [Principal ideas/results] The approach is used by domain experts to specify natural language requirements on a service-based system, and by choreography designers to adapt their models to satisfy requirements more effectively. Non-functional requirements are mapped to BPMN choreography diagrams as quality properties, using the Q4BPMN notation, that support analysis and monitoring facilities. [Contribution] We report the new integrated approach and provide lessons learned from applying it to a real-world example of dynamic taxi management. [ABSTRACT FROM AUTHOR]

We propose a mediation framework supporting a flexible management of choreographed services. The framework separates the management of the business logic of a service from the message flow details reported in the choreography specification. This abstraction step is achieved by introducing an event-driven management of Web Services and by exploiting a rich coordination context which includes business data and synchronization information. By separating activity management issues from communication details, our framework facilitates the management of interaction protocol mismatches between Web Services. [ABSTRACT FROM AUTHOR]

A fundamental promise of service oriented architecture (SOA) lies in the ease of integrating sharable information, processes, and other resources through interactions among the shared components that are modeled as web services. It is expected that not only the participating services are complex and have observable states, but the number of interacting services may be also large. Prior work on choreographies (conversation protocols) all focuses on specifying how the interacting web services should behave globally. Studies have shown that the relationships between global and local specifications of service interactions could be rather intricate. In this paper, we formulate a framework consisting of logical and implementation levels. We survey and discuss the technical problems and known results concerning service design, analysis and verification in this framework. [ABSTRACT FROM AUTHOR]

Web Services technology is constantly gaining importance for automation of business processes. A major contribution of this technology is its integration capability, i.e. compositions allowing several autonomous but cooperating web services to implement a business process going beyond the boundaries of a single organization. Federated choreographies provide a framework for modular modeling complex collections of choreographies and orchestrations. In this paper we present a conformance test to check the structural conformance of the choreographies and orchestration of the proposed model in order to hold the model structurally consistent. We can formally check whether an orchestration realizing (one part of) a choreography, resp. two related choreographies fit together. [ABSTRACT FROM AUTHOR]

Choreographies offer means to capture global interactions between business processes of different partners. BPEL4Chor has been introduced to describe these interactions using BPEL. Currently, there are no formal methods available to verify BPEL4Chor choreographies. In this paper, we present how BPEL4Chor choreographies can be verified using Petri nets. A case study undermines that our verification techniques scale. Additionally, we show how the verification techniques can be used to generate a stub process for a partner taking part in a choreography. This is especially useful when the behavior of one participant is intended to follow the corresponding requirements of the other participants. Thus, the missing participant behavior can be generated and the error-prone design of that participant can be skipped. [ABSTRACT FROM AUTHOR]

Services provide a universal basis for the integration of business processes that are distributed among entities, both within an organization and across organizational borders. Service-oriented Architectures (SOA) include service composition, management and monitoring, billing and security. This paper presents a model-driven approach to design interoperable holonic multiagent systems in a SOA. Thereby, we mainly concentrate on providing a foundation for how to define the composition of services in holonic multiagent systems and discuss how this integragtion could be done in a MDD manner. [ABSTRACT FROM AUTHOR]

Service choreography has become an emerging and promising technology to design and build complex cross-enterprise business applications. Dynamic composition of services on the fly requires mechanisms for ensuring that the component services in the composition are compatible with each other. Current service composition languages provide notations for describing the interactions among component services. However, they focus only on the compatibility at the syntax and semantic level in an informal way, yet ignoring the dynamic behavior within services. This paper emphasizes the importance of the behavior in the compatibility verification between services and utilizes the π-calculus to model the service behavior and the interaction in a formal way. Based on the formalization, it proposes a method based on the operational semantics of the π-calculus to automate the verification of compatibility between two services and presents an algorithm to measure the compatibility degree quantitatively. [ABSTRACT FROM AUTHOR]

A significant development in business process modeling over recent years has involved the B2B choreography perspective, where message exchanges between collaborating partners are explicitly captured. Most of the proposals to date have focused on how message exchanges can be captured through a shared, global perspective between collaborating partners and used to enforce the ordering of individual message send and receive tasks within the processes of the partners. In the wider setting of analysis and design, the B2B perspective represents an important context through which requirements for information systems and their business processes are elicited, as seen through numerous informal methods and techniques. In this chapter, we address the gap between high-level analysis and detailed design concerning the B2B context, proposing extensions for choreography languages to allow for modeling of this context to be seamless across the analysis and design phases. Based on an example taken from the supply chain management domain, we identify three important requirements for extensions: functional scoping of different areas concerning a domain, which can then be modeled and related to each other in isolation; stepwise refinement of choreography models, reminiscent of classical analysis techniques; and the introduction of conversation semantics expressing the intent of logically related message exchanges of choreographies. Accordingly, we propose extensions to choreography modeling and an improved analysis of requirements, such as breakdowns in negotiations that take place between collaborating partners, using an adaptation of BPMN. [ABSTRACT FROM AUTHOR]

We propose a methodology for statically predicting the possible interaction patterns of services within a given choreography. We focus on choreographies exploiting the event notification paradigm to manage service interactions. Control Flow Analysis techniques statically approximate which events can be delivered to match the choreography constraints and how the multicast groups can be optimised to handle event notification within the service choreography. [ABSTRACT FROM AUTHOR]

Web services are the main pillar of the Service Oriented Computing (SOC) paradigm which enables applications integration within and across business organizations. One of the important features of the Web services is the choreography aspect which allows to capture collaborative processes involving multiple services. In this context, one of the important investigations is the choreography compatibility analysis. We mean by the choreography compatibility the capability of a set of Web services of actually interacting by exchanging messages in a proper manner. Whether a set of services are compatible depends not only on their sequences of messages but also on quantitative properties such as timed properties. In this paper, we investigate an approach that deals with checking the timed compatibility of a choreography in which the Web services support asynchronous timed communications. [ABSTRACT FROM AUTHOR]

Choreography conformance and contract compliance have been widely studied in the context of synchronous communication. In this paper we approach a more realistic scenario in which the messages containing the invocations are queued in the called service. More precisely, we study the foundational aspects of contract compliance in a language independent way by just taking contracts to be finite labeled transition systems. Then, we relate the proposed theory of contract compliance with choreography specifications à la WS-CDL where activities are interpreted as pairs of send and receive events. An interesting consequence of adopting a language independent representation of contracts is that choreography projection can be defined in structured operational semantics. [ABSTRACT FROM AUTHOR]

Evolving business needs call for customizing choreographed interactions. However, conventional choreography description languages provide only a partial view of the interaction. Business goals of each participant and organizational dependencies motivating the interaction are not captured in the specification of messaging. Absence of this critical business knowledge makes it hard to reason if a particular customization satisfies the goals of participants. Furthermore, there is no systematic means to assess the impact of change in one participant΄s process (local view) on the choreography (global view) as well as on other participants΄ processes. To this end, we argue for the benefits of representing choreography at the level of requirements motivating the interaction. We propose a framework that allows participants to collaborate on customizing choreographed interactions, while reconciling their competing business needs. To bridge the worlds of messaging and requirements, we employ an automated technique for deriving a choreography description from the customized requirements. [ABSTRACT FROM AUTHOR]

The Lightweight Coordination Calculus (LCC) is a compact choreography language based on process calculus. LCC is a directly executable specification and can therefore be dynamically distributed to a group of peers for enactment at run-time; this offers flexibility and allows peers to coordinate in open systems without prior knowledge of an interaction. This paper contributes to the body of choreography research by proposing two extensions to LCC covering parallel composition and choreography abstraction. These language extensions are evaluated against a subset of the Service Interaction Patterns, a benchmark in the process modelling community. [ABSTRACT FROM AUTHOR]

Choreography models describe the communication protocols between services. Testing of service choreographies is an important task for the quality assurance of service-based systems as used e.g. in the context of service-oriented architectures (SOA). The formal modeling of service choreographies enables a model-based integration testing (MBIT) approach. We present MBIT methods for our service choreography modeling approach called Message Choreography Models (MCM). For the model-based testing of service choreographies, MCMs are translated into Event-B models and used as input for our test generator which uses the model checker ProB. [ABSTRACT FROM AUTHOR]