Year of publication
- Lehrstuhl für Praktische Informatik (112)
- Fakultät Wirtschaftsinformatik und Angewandte Informatik (2)
- Lehrstuhl für Angewandte Informatik in den Kultur-, Geschichts- und Geowissenschaften (2)
- Professur für Informatik, insbesondere Kommunikationsdienste, Telekommunikationssysteme und Rechnernetze (2)
- Lehrstuhl für Medieninformatik (1)
- Lehrstuhl für Wirtschaftsinformatik, insbesondere Industrielle Informationssysteme (1)
- Lehrstuhl für Wirtschaftsinformatik, insbesondere Systementwicklung und Datenbankanwendung (1)
- Professur für Angewandte Informatik, insbesondere Kognitive Systeme (1)
- Professur für Grundlagen der Informatik (1)
- Building Orchestrations in B2Bi – The Case of BPEL 2.0 and BPMN 2.0 (2012)
- Various approaches for service-oriented business-to-business integration (B2Bi) rely on a top-down development methodology. The starting point is a choreography model which is subsequently partitioned into multiple orchestrations. Most current approaches use the Web Services Business Process Execution Language (BPEL) for implementing the latter. At the same time, a plethora of other languages, such as Business Process Model and Notation (BPMN) 2.0 process diagrams, is available. As integration partners are free to select the orchestration language of their choice, it should be easy to integrate different orchestration languages with current choreography technology. Language transformation, starting from a suitable format, is a means to achieve this. In this paper, we assess BPEL 2.0 and BPMN 2.0 process diagrams for their suitability for this transformation in a services-based B2Bi setting using a requirements framework identified through a literature study.
- Bridging the Heterogeneity of Orchestrations – A Petri Net–based Integration of BPEL and Windows Workflow (2012)
- Service orchestrations are a powerful tool for implementing intra– and interorganizational business processes that base on services. Several heterogeneous orchestration languages can be found in contemporary IT landscapes. While the Web Services Business Process Execution Language (BPEL) is the de facto standard, others gain attention, including Windows Workflow (WF) in the .NET segment. When integrating orchestrations, incompatibilities between them can easily arise. In this paper, we investigate an automated Petri net–based integration between BPEL and WF to solve these issues with behavioral adapter services. We provide a mapping of WF to Open Workflow Nets (oWFNs) and implement it in a compiler. Thereby, we integrate our approach with existing approaches for BPEL and adapter synthesis and validate the integration with a standards–based case study using the two languages.
- BPEL Conformance in Open Source Engines (2012)
- More than five years have passed since the final release of the long-desired OASIS standard of a process language for Web Services orchestration, the Web Services Business Process Execution Language (BPEL). The aim of this standard was to establish a universally accepted Web Services orchestration language that forms a core part of service-oriented architectures and, because of standardization, avoids vendor lock-in. By now, several fully conformant engines should have arrived in the market. It is our aim to shed light on this situation and to provide a comprehensive picture of the current state of BPEL upport. We present an evaluation of the standard conformance of five open source BPEL engines. To obtain these results we have developed betsy, a tool that allows for a fully-automatic standard conformance testing of BPEL engines. The results demonstrate that full standard conformance in contemporary engines is still far from given.
- Detecting Interoperability and Correctness Issues in BPMN 2.0 Process Models (2013)
- Although BPMN 2.0 is an international standard widely used in practice, interoperability of process models is still an issue. Even between tools and engines claiming to be BPMN compliant the model exchange is often complicated or impossible as the tools produce incorrect model representations or do not support the standardized BPMN serialization format. In this position paper we present reasons for interoperability issues and show why defining a set of constraints derived from the standard is crucial to fix an important subset of those issues. We are currently developing a tool which can check this set of rules automatically.
- Detecting Portability Issues in Model-Driven BPEL Mappings (2013)
- Service orchestration languages, like the Web Services Business Process Execution Language (BPEL), have been frequently used to provide an implementation platform for model-driven development approaches. As avoidance of vendor lock-in and portability of process definitions are central aims of BPEL, most approaches claim to support a large set of different runtime environments. But, even though today various runtimes for BPEL are available, every runtime implements a different language subset, thus hampering portability. Our idea is to improve this situation by using techniques, the Web Services Interoperability Organization (WS-I) has used to improve services interoperability. We describe a portability profile for BPEL that can detect portability issues in process definitions. Using this profile, we evaluate the portability of BPEL mappings used in several model-driven development approaches.
- Measuring the Portability of Executable Service-Oriented Processes (2013)
- A key promise of process languages based on open standards, such as the Web Services Business Process Execution Language, is the avoidance of vendor lock-in through the portability of process definitions among runtime environments. Despite the fact that today, various runtimes claim to support this language, every runtime implements a different subset, thus hampering portability and locking in their users. In this paper, we intend to improve this situation by enabling the measurement of the degree of portability of process definitions. This helps developers to assess their process definitions and to decide if it is feasible to invest in the effort of porting a process definition to another runtime. We define several software quality metrics that quantify the degree of portability a process definition provides from different viewpoints. We validate these metrics theoretically with two validation frameworks and empirically with a large set of process definitions coming from several process libraries.
- BPMN 2.0 Serialization - Standard Compliance Issues and Evaluation of Modeling Tools (2013)
- Business Process Model and Notation (BPMN) 2.0 process models are used more and more, both in practice as in academia. Although academic research mainly focuses on sophisticated semantic checks and extensions there still exist problems in the basic usage of BPMN. This paper investigates issues in BPMN model serializations which arise as a result of the complexity and inconsistency of the standard document. We present a set of serialization constraints as a starting point for sophisticated compliance checks on serialized BPMN models. Furthermore, these constraints are used to perform an evaluation of current modeling tools. This evaluation reveals that the creation of standard compliant models is still a non-trivial endeavor.
- Measuring the Installability of Service Orchestrations Using the SQuaRE Method (2013)
- Service-oriented software consists of middleware, such as application servers and runtime engines, into which service applications are deployed. This middleware is often complex and difficult to install. The deployment of services requires the crafting of deployment descriptors and packaging of applications. As a consequence, the installation of service-oriented software systems can be a daunting task. Installability, however, is an important influencer of the portability of software. Portability in turn is one of the main goals of service orchestration languages based on open standards. In this paper, we investigate the installability of service orchestrations based on the Systems and software Quality Requirements and Evaluation (SQuaRE) method, the new series of software qual- ity standards currently under development by the ISO/IEC. We develop a measurement framework based on SQuaRE and tailored to evaluating the installability of service orchestrations and their runtimes. We validate the measurement framework theoretically and show its applicability in a case study.
- Towards Application Portability in Platform as a Service (2014)
- Cloud Computing has been one of the most vibrant topics in the last years. Especially Platform as a Service (PaaS) is said to be a game changer for future application development. Taking away most of the configuration work, it pledges to foster rapid application development which seems even more important in a world of complex scalable distributed systems. Whereas Infrastructure as a Service (IaaS) is in the process of consolidation and standardization, the PaaS market is largely fragmented offering varying ecosystem capabilities. In this situation, application portability is a major concern for companies utilizing PaaS to avoid vendor lock-in and to retain the ability for future strategical decisions. To categorize portability problems of PaaS, we define a model of current PaaS offerings and identify different portability perspectives. Starting from the model, we derive a standardized profile with a common set of capabilities that can be found among PaaS providers and matched with one another to check application portability based on ecosystem capabilities. We validate our findings with a comprehensive data set of 68 PaaS offerings together with a web-based application for portability matching. We also identify further portability problems by porting the application to different PaaS vendors, validating ecosystem portability and giving hints for future research directions.