Abstract—Complex networks consisting of humans and software services, such as Web-based social and collaborative environments, typically require flexible and context-based interaction models. Due to the dynamics in such systems, networks are in a state of constant flux and change. Several fundamental concepts, including discovery, interactions, task delegations and executions are no longer based on static policies, but need periodic readjustments. Sophisticated adaptation techniques for improving collaborations are within the key research areas in service-oriented systems. In this paper, we introduce an adaptation approach that accounts for emerging trust relations based on varying interaction behavior of network members. We describe a science collaboration scenario that applies adaptive information sharing techniques. In our model, trust evolves from cooperative behavior of collaboration partners. This behavioral trust provides an intuitive grounding for adaptations and optimizations of member compositions and sharing policies. As people prove their reliable and dependable behavior in jointly performed activities, they become increasingly considered as invaluable partners. We describe the foundational concepts, including support for ad-hoc and selfmanaged collaboration scenarios, and dynamic trust determination supported by SOA concepts. Furthermore, we present a reference architecture, and evaluate its applicability for largescale collaboration networks. Keywords-trust-based adaptation, complex mixed systems, trust emergence, trust-based information views; I.

Web services have emerged as a technology for designing and composing distributed applications. Recent research increasingly addressed the need to adapt such systems based on changing requirements and environmental constraints. From the developers point of view, it is already a daunting task to update the description, implementation, or configuration of individual services that are already deployed in the runtime environment. A major undertaking is update and maintenance of large scale service environments. In this work, we introduce a programming model enabling the adaptation and evolution of service-oriented systems in a simple and intuitive way. Most existing work focuses on self-adaptation aspects. We present a user-centric approach and a framework supporting both automatic mechanisms for adaptation and foremost a programming model to reduce the burden of reconfiguration, update, and customization of service-based applications. We implemented the programming model on top of Genesis, aJava-based Web services framework.

Abstract—In this paper, we address the problem of selfadaptation in internet-scale service-oriented systems. Services need to adapt by select the best neighboring services solely based on local, limited information. In such complex systems, the global significance of the various selection parameters dynamically changes. We introduce a novel metric measuring the distribution and potential impact of service properties affecting such selection parameters. We further present an formalism identifying the most significant properties based on aggregated service interaction data. We ultimately provide a ranking algorithm exploiting these dynamic interaction characteristics. Experimental evaluation demonstrates scalability and adaptiveness of our approach. I.

Service-based systems that are dynamically composed at run time to provide complex, adaptive functionality are currently one of the main development paradigms in software engineering. However, the Quality of Service (QoS) delivered by these systems remains an important concern, and needs to be managed in an equally adaptive and predictable way. To address this need, we introduce a novel, tool-supported framework for the development of adaptive service-based systems called QoSMOS (QoS Management and Optimisation of Service-based systems). QoSMOS can be used to develop service-based systems that achieve their QoS requirements through dynamically adapting to changes in the system state, environment and workload. QoSMOS service-based systems translate high-level QoS requirements specified by their administrators into probabilistic temporal logic formulae, which are then formally and automatically analysed to identify and enforce optimal system configurations. The QoSMOS self-adaptation mechanism can handle reliability- and performance-related QoS requirements, and can be integrated into newly developed solutions or legacy systems. The effectiveness and scalability of the approach are validated using simulations and a set of experiments based on an implementation of an adaptive service-based system for remote medical assistance.

The aim of this deliverable is two-fold. Firstly, it depicts the research vision of the workpackage, including the research challenges that will be addressed by the S-Cube consortium. Secondly, the deliverable aims at defining the S-Cube quality reference model. This reference model is intended to provide the S-Cube consortium with a unified terminology for describing different quality attributes of service-based applications. To this end, important quality models from service-oriented computing, business process management, grid computing and software engineering are analyzed. The quality attributes which are defined in these models and which are relevant for S-Cube are extracted and synthesized into the S-Cube quality reference model. Copyright © 2009 by the S-CUBE consortium – All rights reserved. The research leading to these results has received funding from the European Community's Seventh Framework Programme [FP7/2007-2013] under grant agreement n ° 215483 (S-Cube).S-Cube

Web-based collaborations have become essential in today’s business environments. Due to the availability of various SOAframeworks, Webservices emerged as the defacto technology to realize flexible compositions of services. While most existing work focuses on the discovery and composition of software based services, we highlight concepts for a people-centric Web. Knowledge-intensive environments clearly demand for provisioning of human expertise along withsharingofcomputingresourcesorbusinessdatathrough software-based services. To address these challenges, we introduce an adaptive approach allowing humans to provide their expertise through services using SOA standards, such as WSDL and SOAP. The seamless integration of humans in the SOA loop triggers numerous social implications, such as evolving expertise and drifting interests of human service providers. Here we propose a framework that is based on interaction monitoring techniques enabling adaptations in SOA-based socio-technical systems.

Abstract—Flexible interactions in complex social and serviceoriented collaboration systems increasingly demand for automated adaptation techniques to optimize partner discovery and selection. Today, applications of complex service-oriented systems can be found in crowdsourcing environments. In such environments, collaborations are typically short-lived and strongly influenced by incentives and actor behavior. As actors prove their reliable and dependable behavior in jointly performed activities, they become increasingly considered as invaluable partners. A social network builds a strong basis to enable successful collaborations between crowd members. In order to keep track of the dynamics in such systems, it is inevitable to apply an autonomous approach to manage social network structures automatically using captured interaction data. Thus, we introduce an adaptation concept that accounts for emerging social relations based on varying interaction behavior of collaboration partners. We describe the foundational concepts for dynamic social link management in Web-based collaborations. We highlight major concerns of computational models in highly dynamic networks and deal with temporal aspects such as supporting the emergence of relations, efficient update mechanisms, and aging of relations. Keywords-computational social network management; emergence of social relations; service-oriented crowdsourcing I.

Abstract. RosettaNet is a leading industry effort that creates standards for business interactions. The RosettaNet standard defines over 100 Partner Interface Processes (PIPs). The PIPs specify the business interactions at a syntactic level, but they fail to capture the business semantics of those interactions. This paper builds on a commitment-based approach for business modeling. It presents an approach that defines commitment-based business patterns abstracted from Rosetta-Net PIPs. This paper validates the patterns by using them to model a well-known real-life use case of a cross-organizational business interaction. 1

Open-world software is a paradigm which allows to develop distributed and heterogeneous software systems. They can be built by integrating already developed third-party services, which use to declare QoS values (e.g., related to performance). It is true that these QoS values are subject to some uncertainties. Consequently, the performance of the systems using these services may unexpectedly decrease. A challenge for this kind of software is to self-adapt its behavior as a response to changes in the availability or performance of the required services. In this paper, we develop an approach to model self-renconfigurable open-world software systems with stochastic Petri nets. Moreover, we develop strategies for a system to gain a new state where it can recover its availability or even improve its performance. Through an example, we apply these strategies and evaluate them to discover suitable reconfigurations for the system. Results will announce appropriate strategies for system performance enhancement.

This deliverable presents two distinct bodies of knowledge: the first one is for service oriented computing based on a proposed life cycle that incorporates adaptation-specific phases. Each phase is discussed in depth, and methods, techniques and tools for it are presented. Furthermore, cross-phase aspects are investigated. The other body of knowledge concerns more traditional software engineering and business process methodologies, examined from the perspective of service based applications. A number of preliminary results on the synergy between the two areas are also presented as a stepping stone for the following deliverables. Copyright © 2008 by the S-CUBE consortium – All rights reserved. The research leading to these results has received funding from the European Community's Seventh Framework Programme [FP7/2007-2013] under grant agreement n ° 215483 (S-Cube). File name: CD-JRA-1.1.2.pdfS-CUBE