Forum Session at the First International Conference on Service Oriented Computing (ICSOC03)

The First International Conference on Service Oriented Computing (ICSOC) was held in Trento, December 15-18, 2003. The focus of the conference ---Service Oriented Computing (SOC)--- is the new emerging paradigm for distributed computing and e-business processing that has evolved from object-oriented and component computing to enable building agile networks of collaborating business applications distributed within and across organizational boundaries. Of the 181 papers submitted to the ICSOC conference, 10 were selected for the forum session which took place on December the 16th, 2003. The papers were chosen based on their technical quality, originality, relevance to SOC and for their nature of being best suited for a poster presentation or a demonstration. This technical report contains the 10 papers presented during the forum session at the ICSOC conference. In particular, the last two papers in the report ere submitted as industrial papers

Quality-aware model-driven service engineering

Service engineering and service-oriented architecture as an integration and platform technology is a recent approach to software systems integration. Quality aspects ranging from interoperability to maintainability to performance are of central importance for the integration of heterogeneous, distributed service-based systems. Architecture models can substantially influence quality attributes of the implemented software systems. Besides the benefits of explicit architectures on maintainability and reuse, architectural constraints such as styles, reference architectures and architectural patterns can influence observable software properties such as performance. Empirical performance evaluation is a process of measuring and evaluating the performance of implemented software. We present an approach for addressing the quality of services and service-based systems at the model-level in the context of model-driven service engineering. The focus on architecture-level models is a consequence of the black-box character of services

A Multiagent System for the Reliable Execution of Automatically Composed Ad-hoc Processes

This article presents an architecture to automatically create ad-hoc processes for complex value-added services and to execute them in a reliable way. The uniqueness of ad-hoc processes is to support users not only in standardized situations like traditional workflows do, but also in unique non-recurring situations. Based on user requirements, a service composition engine generates such ad-hoc processes, which integrate individual services in order to provide the desired functionality. Our infrastructure executes ad-hoc processes by transactional agents in a peer-to-peer style. The process execution is thereby performed under transactional guarantees. Moreover, the service composition engine is used to re-plan in the case of execution failure

Web Services Support for Dynamic Business Process Outsourcing

Outsourcing of business processes is crucial for organizations to be effective, efficient and flexible. To meet fast-changing market conditions, dynamic outsourcing is required, in which business relationships are established and enacted on-the-fly in an adaptive, fine-grained way unrestricted by geographic distance. This requires automated means for both the establishment of outsourcing relationships and for the enactment of services performed in these relationships over electronic channels. Due to wide industry support and the underlying model of loose coupling of services, Web services increasingly become the mechanism of choice to connect organizations across organizational boundaries. This paper analyzes to which extent Web services support the dynamic process outsourcing paradigm. We discuss contract -based dynamic business process outsourcing to define requirements and then introduce the Web services framework. Based on this, we investigate the match between the two. We observe that the Web services framework requires further support for cross - organizational business processes and mechanisms for contracting, QoS management and process-based transaction support and suggest ways to fill those gaps

SECURITY POLICY ENFORCEMENT IN APPLICATION ENVIRONMENTS USING DISTRIBUTED SCRIPT-BASED CONTROL STRUCTURES

Business processes involving several partners in different organisations impose demanding requirements on procedures for specification, execution and maintenance. A framework referred to as business process management (BPM) has evolved for this purpose over the last ten years. Other approaches, such as service-oriented architecture (SOA) or the concept of virtual organisations (VOs), assist in the definition of architectures and procedures for modelling and execution of so-called collaborative business processes (CBPs). Methods for the specification of business processes play a central role in this context, and, several standards have emerged for this purpose. Among these, Web Services Business Process Execution Language (WS-BPEL, usually abbreviated BPEL) has evolved to become the de facto standard for business process definition. As such, this language has been selected as the foundation for the research in this thesis. Having a broadly accepted standard would principally allow the specification of business processes in a platform-independent manner, including the capability to specify them at one location and have them executed at others (possibly spread across different organisations). Though technically feasible, this approach has significant security implications, particularly on the side that is to execute a process. The research project focused upon these security issues arising when business processes are specified and executed in a distributed manner. The central goal has been the development of methods to cope with the security issues arising when BPEL as a standard is deployed in such a way exploiting the significant aspect of a standard to be platform-independent The research devised novel methods for specifying security policies in such a manner that the assessment of compliance with these policies is greatly facilitated such that the assessment becomes suited to be performed automatically. An analysis of the securityrelevant semantics of BPEL as a specification language was conducted that resulted in the identification of so-called security-relevant semantic patterns. Based on these results, methods to specify security policy-implied restrictions in terms of such semantic patterns and to assess the compliance of BPEL scripts with these policies have been developed. These methods are particularly suited for assessment of remotely defined BPEL scripts since they allow for pre-execution enforcement of local security policies thereby mitigating or even removing the security implications involved in distributed definition and execution of business processes. As initially envisaged, these methods are comparatively easy to apply, as they are based on technologies customary for practitioners in this field. The viability of the methods proposed for automatic compliance assessment has been proven via a prototypic implementation of the essential functionality required for proof-of-concept.Darmstadt Node of the NRG Network at University of Applied Sciences Darmstad

Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow