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Ramaratnam, Rajiv. "An analysis of service oriented architectures." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42372.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2007.Leaf 96 blank.
Includes bibliographical references (leaves 88-95).
Introduction: Corporations all across the globe and of various sizes rely on their IT systems for business processes, reduction of process lifecycle and management of resources. These systems house several applications for internal sales, purchasing, finance, HR and so on. In any such typical organization, IT systems are a heterogeneous mix of hardware, operating systems and applications. Many of these applications run on different operating systems like Windows systems, Linux and Unix systems, etc. Oftentimes there is a need to consolidate data or access data from several such systems. The diversity among systems and applications makes these tasks difficult, time consuming and tedious. Furthermore, there is also a need for synchronization of data across systems and applications to ensure that the data is accurate and up-to-date. The heterogeneous nature of systems and applications lead to high levels of redundancy of data, making data maintenance a huge overhead for organizations. Today's organizations must also adapt to changes in environments both external and internal to them. Such changes could be changing market conditions, reorganization, change in business strategies within a company, addition or changing suppliers, partnerships, mergers and acquisitions and so on. There is also a growing need for integration across enterprise boundaries to facilitate fast and seamless collaboration between partners, customers and suppliers. All such needs entail changes to existing IT systems within an organization in a timely manner. There is thus a growing need for integration of such systems for consolidated decision making, accurate, up-to-date system information, better performance and system monitoring. IT Systems must also be flexible to respond to changes in the environments of their organization. Enterprise Application Integration is a process that aims to bring about such integration. The need for integration goes beyond the boundaries of an enterprise. Further, to successfully compete today, businesses need to be flexible. This means that their IT systems need to be able to keep pace with dynamic business conditions. It is evident that any solution for multiple IT systems to integrate with each other and to provide flexibility, they must be able to communicate and coordinate activities in a standard way. For almost two decades, many companies have tried to use CORBA, DCOM and similar technologies but have had little success. None of these technologies, for many reasons have become global technologies. The arrival of standards like HTTP and HTML helped linking together millions of humans across the internet but proved inadequate to link together computer systems. Moreover, internal and cross enterprise integration and coordination bring with them, security implications as both involve information exchange between organizational entities. As we will see later, the traditional methods of securing applications with firewalls prove inadequate for application security. One insight that has come from failed attempts to consolidate and coordinate IT systems is that such efforts cannot be limited to IT alone. Decision making on how interdepartmental and inter-enterprise data must data must be exchanged must be made by leaders and opinion shapers at each level or division of the organization. It is the goals of internal and external enterprise integration, flexibility of business processes, and enterprise data security that has led more and more organizations to adopt to Service Oriented Architectures (SOA). The adoption, implementation and running of a SOA does not simply involve IT department heads to design and create a new architecture for the enterprise. It involves a holistic understanding of the nature of the entire enterprise, its business and internal processes, the corporate strategy for the enterprise, an understanding of the business processes of the enterprise, its partners, suppliers, subsidiaries, etc. Such an undertaking is beyond the scope of a single department or division of the enterprise. The creation and running SOA architecture thus involves the coordination of all parts of the enterprise.
by Rajiv Ramaratnam.
S.M.
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Gamble, Carl Jeffrey. "Design time detection of architectural mismatches in service oriented architectures." Thesis, University of Newcastle Upon Tyne, 2011. http://hdl.handle.net/10443/1241.
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Service Oriented Architecture (SOA) is a software component paradigm that has the potential to allow for exible systems that are loosely coupled to each other. They are discoverable entities that may be bound to at run time by a client who is able to use the service correctly by referring to the service's description documents. Assumptions often have to be made in any design process if the problem domain is not fully speci ed. If those decisions are about the software architecture of that component and it is inserted into a system with di ering and incompatible assumptions then we say that an architectural mismatch exists. Architectural styles are a form of software reuse. They can simply be used by referring to a name such as \client-server" or \pipe and lter", where these names may conjure up topologies and expected properties in the architects mind. They can also however be more rigorously de ned given the right software environment. This can lead to a vocabulary of elements in the system, de ned properties of those elements along with rules and analysis to either show correctness of an implementation or reveal some emergent property of the whole. SOA includes a requirement that the service components make available descriptions of themselves, indicating how they are to be used. With this in mind and assuming we have a suitable description of the client application it should be the case that we can detect architectural mismatches when designing a new system. Here designing can range from organising a set of existing components into a novel con guration through to devising an entirely new set of components for an SOA. This work investigates the above statement using Web Services as the SOA implementation and found that, to a degree, the above statement is true. The only element of description required for a web service is the Web Service Description Language (WSDL) document and this does indeed allow the detection of a small number of mismatches when represented using our minimal web service architectural style. However from the literature we nd that the above mismatches are only a subset of those that we argue should be detectable. In response to this we produce an enhanced web service architectural style containing properties and analysis supporting the detection of this more complete set of mismatches and demonstrate its e ectiveness against a number of case studies.
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Al-Humam, Abdulaziz. "Service-oriented architectures for safety-critical systems." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/11823/.
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Many organisations in the safety-critical domain are service-oriented, fundamentally centred on critical services provided by systems and operators. Increasingly, these services rely on software-intensive systems, e.g. medical health informatics and air traffic control, for improving the different aspects of industrial practice, e.g. enhancing efficiency through automation and safety through smart alarm systems. However, many services are categorised as high risk and as such it is vital to analyse the ways in which the software-based systems can contribute to unintentional harm and potentially compromise safety. This thesis defines an approach to modelling and analysing Service-Oriented Architectures (SOAs) used in the safety-critical domain, with emphasis on identifying and classifying potential hazardous behaviour. The approach also provides a systematic and reusable basis for defining how the safety case for these SOAs can be developed in a modular manner. The approach is tool-supported and is evaluated through two case studies, from the healthcare and oil and gas domains, and industrial review.
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Mayer, Philip. "MDD4SOA: Model-Driven Development for Service-Oriented Architectures." Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-124405.
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Giese, Holger, and Basil Becker. "Modeling and verifying dynamic evolving service-oriented architectures." Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6511/.
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The service-oriented architecture supports the dynamic assembly and runtime reconfiguration of complex open IT landscapes by means of runtime binding of service contracts, launching of new components and termination of outdated ones. Furthermore, the evolution of these IT landscapes is not restricted to exchanging components with other ones using the same service contracts, as new services contracts can be added as well. However, current approaches for modeling and verification of service-oriented architectures do not support these important capabilities to their full extend.In this report we present an extension of the current OMG proposal for service modeling with UML - SoaML - which overcomes these limitations. It permits modeling services and their service contracts at different levels of abstraction, provides a formal semantics for all modeling concepts, and enables verifying critical properties. Our compositional and incremental verification approach allows for complex properties including communication parameters and time and covers besides the dynamic binding of service contracts and the replacement of components also the evolution of the systems by means of new service contracts. The modeling as well as verification capabilities of the presented approach are demonstrated by
means of a supply chain example and the verification results of a first prototype are shown.Service-Orientierte Architekturen erlauben die dynamische Zusammensetzung und Rekonfiguration komplexer, offener IT Landschaften durch Bindung von Service Contracts zur Laufzeit, starten neuer Komponenten und beenden von veralteten. Die Evolution dieser Systeme ist nicht auf den Austausch von Komponenten-Implementierungen bei Beibehaltung der Service-Contracts beschränkt, sondern das Hinzufügen neuer Service-Contracts wird ebenfalls unterstützt. Aktuelle Ansätze zur Modellierung und Verifikation Service-Orientierter Architekturen unterstützen diese wichtigen Eigenschaften, wenn überhaupt, nur unvollständig. In diesem Bericht stellen wir eine Erweiterung des aktuellen OMG Vorschlags zur Service Modellierung mit UML - SoaML - vor, die diese Einschränkungen aufhebt. Unser Ansatz erlaubt die Modellierung von Service Contracts auf verschiedenen Abstraktionsniveaus, besitzt eine fundierte formale Semantik für alle eingeführten Modellierungskonzepte und erlaubt die Verifikation kritischer Eigenschaften. Unser kompositionaler und inkrementeller Verifikationsansatz erlaubt die Verifikation komplexer Eigenschaften einschließlich Kommunikationsparameter und Zeit und deckt neben der dynamischen Bindung von Service Contracts sowie dem Austausch von Komponenten auch die Evolution des gesamten Systems durch das Hinzufügen neuer Service Contracts ab. Die Modellierungs- als auch die Verifikationsfähigkeiten unseres vorgestellten Ansatzes werden durch ein Anwendungsbeispiel aus dem Bereich des Lieferkettenmanagements veranschaulicht.
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Thomas, Jamar. "Asynchronous instant messaging using service-oriented architectures (aimsoa)." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2005. http://digitalcommons.auctr.edu/dissertations/1251.
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Instant messengers suffer from poor scalability, flexibility, security, and interoperability. This study attempts to solve these problems using the strengths of Service-Oriented Architectures. The key components to achieve these improvements include several Java related technologies such as JAX-RPC, JAXM, SOAP, WSDL, J2EE servlets and Enterprise Java Beans. SOAP provides a universal messaging protocol that heterogeneous parties can understand. JAX-RPC provides synchronous SOAP messaging, as well as a loosely coupled design that allows for a very flexible distributed architecture. JAXM provides asynchronous SOAP messaging. When used together, applications can implement robust instant messaging functionality. Registration, login, and other instant messaging configuration operations can be fulfilled through the use of JAX-RPC while JAXM can be used to fulfill requirements such as send and receive. Servlets and Enterprise Java Beans augment the benefits of Service-Oriented Architectures with the former being extremely scalable, portable, and modular. AIMSOA encapsulates these components to provide an instant messaging architecture solution that will augment the weaknesses of current instant messaging architectures by providing a solution for better scalability, flexibility, and interoperability.
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Norman, David. "The value proposition of service-oriented architecture." [Denver, Colo.] : Regis University, 2008. http://165.236.235.140/lib/DNorman2008.pdf.
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Friesen, Andreas [Verfasser]. "Secure Subscription Management for Service-oriented Architectures / Andreas Friesen." Aachen : Shaker, 2004. http://d-nb.info/1170535038/34.
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Krähenbühl, Alexander. "Soability assessment, planning, and management of service oriented architectures." Saarbrücken VDM, Müller, 2006. http://d-nb.info/987710737/04.
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González, Cela Alberto José. "Contributions to the future media internet using service-oriented architectures." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/96783.
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Nowadays, video streaming applications are the most bandwidth-hungry applications and this tendency is envisaged to grow
exponentially. With the proliferation of multimedia capable devices, multimedia services have to deal with heterogeneous
environments where very different types of terminals wish to receive content anywhere and anytime. This situation motivates
the appearance of multimedia services that adapt contents to the specific context of users. These services can benefit from
the use of different technologies for content delivery (e.g. Peer-to-Peer and Network Coding), media signalling (e.g. SIP and
P2P protocols), media representation (e.g. MPEG-7 and MPEG-21) or multimedia scalable and robust codification (e.g.
Multiple Description Coding and Scalable Video Coding). However, current Internet architecture is based on a rigid layered
model (TCP/IP-based) following the, no longer valid, end-to-end argument, which makes difficult to introduce new
functionalities efficiently. To solve this, Service Oriented Architectures (SOA) principles seem to fit in the proposal of new
architectures for a more flexible Future Internet based on services that can be invoked when and where necessary.
The objectives of this PhD. Thesis are exploring and validating different mechanisms for enabling Future Media Internet
communications. To achieve this, we apply the SOA paradigm to provide efficient context-aware multimedia communications
in the Future Internet.
This work proposes solutions to enable the seamless provisioning of multimedia services in the Future Internet by means of
context-aware service discovery and composition processes which are integrated in a novel service-oriented clean-slate
architecture. One goal is to provide adapted and personalized services, dealing with high dynamic and heterogeneous
environments. For this reason, this thesis includes research on novel media coding techniques (Multiple Description Coding,
Scalable Video Coding) and distribution techniques (Peer-to-Peer, Network Coding) that can be applied to achieve seamless
media communications. Moreover, context-aware service composition will address the requirements of media services (and
any service in general), access methods, devices and interactions.
This work presents a radical view of the Future Internet, where the necessary functionalities for accomplishing
communications, in user devices, in the network and at all levels are considered as services. Services are not fixed but
dynamically composed where and when necessary, with respect to user service requirements, network transfer capabilities
and surrounding context in the user and the network environments.
Composition of basic network-level services calls for a clean-slate approach to the Internet, while composition of higher level
(transport and application) services prompts for an evolutionary approach. Nevertheless, composition of communication
services manifests itself as a revolutionary way of looking communications and building communication systems.
This PhD. Thesis introduces two main architectural innovations clearly beyond current state of the art. Firstly, a Service-
Oriented framework able to deal with (existing) functionality at all levels (connectivity, transport, application) by considering the
provided service and not the technology behind the functionality. All these service functionalities can be seen as services
thanks to suitable service-oriented abstractions that allow including existing functionality/protocols as well as new
functionality in a flexible way. Secondly, we present a novel service-oriented clean-slate architecture generalizing Information-
Centric Networking (ICN) approaches. This work would propose the first clean-slate architecture completely aligned with the
work done within the ISO Future Networks working group
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Kervall, Fredrik. "Standards and Business Aspects of Service Oriented Architectures in Healthcare." Thesis, Blekinge Tekniska Högskola, Avdelningen för programvarusystem, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4801.
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Extensive efforts are being conducted in the area of integrating and merging together applications and systems in public administration, including healthcare. One approach against integrating applications is to introduce a Service Oriented Architecture (SOA). This could be conducted by modifying the previously stand-alone systems and make them act as services or components, communicating through some sort of common services or directly interoperate. This thesis describes several standards and best practices addressing integration currently present in healthcare. Additionally, a number of business key aspects connected to Service Oriented Architectures are described and also how customers and contractors could benefit from these. By conducting an industrial case study of an integration project, standards and business aspects could be applied and used to analyze the project. Both software engineering issues and business aspects are identified, important to the study.
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Kongdenfha, Woralak Computer Science & Engineering Faculty of Engineering UNSW. "Pattern-based data and application integration in service oriented architectures." Awarded By:University of New South Wales. Computer Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/42600.
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The success of Web services comes from the benefits that it brings in reducing the cost and the time needed to develop data and applications by reusing them, and simplifying their integrations through standardization. However, standardization in Web services does not remove the need for adapters due to possible heterogeneity among service interface and protocol definitions. Moreover, the current service APIs are targeted toward professional programmers, but not accessible to a wider class of users without programming expertise, but would never the less like to build their own integrated applications. In this dissertation, we propose methods and tools to support both service developers and non-expert users in their data and application integration tasks. To support service developers, we propose a framework that enables rapid development of Web service adapters. We investigate particularly the problem of service adaptation focusing on business interface and protocol layers. Our study shows that many differences between business interfaces and protocols are recurring. We introduce mismatch patterns to capture these recurring differences and provide solutions to resolve them. We present the notion of adaptation aspects, which is based on the aspect-oriented programming paradigm, to enable rapid development and deployment of service adapters. We also present a comparative study between standalone and aspect-oriented adapters development. The study shows that the aspect-oriented approach is preferable in many cases, especially when adapters need to access internal states of services. The proposed approach is implemented in a prototype tool, which is used to illustrate how it simplifies adapters development through a case study. To support users without programming expertise, we propose a spreadsheet-based Web mashups development framework, which enables users to develop mashups in the popular spreadsheet environment. First, we provide a mechanism that makes structured data first class values of spreadsheet cells. Second, we propose a new component model that can be used to develop fairly sophisticated mashups, involving joining data sources and keeping spreadsheet data up to date. Third, to simplify mashup development, we provide a collection of spreadsheet-based mashup patterns that captures common Web data access and spreadsheet presentation functionalities. Users can reuse and customize these patterns to build spreadsheet-based Web mashups instead of developing them from scratch. Fourth, we enable users to manipulate structured data presented on spreadsheet in a drag-and-drop fashion. Finally, we have developed and tested a prototype tool to demonstrate the utility of the proposed framework.
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Lundkvist, Elin, and Gustav Persson. "From guess to success : How to govern service-oriented architectures." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-255163.
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Service-oriented architecture (SOA) governance has been identified as the most important factor affecting the outcome of SOA within organisations. However, authors have failed to explain how organisations should govern specific aspects of its SOA, leaving a gap in the literature. Therefore, the purpose of this study was to investigate established SOA governance mechanisms in order to explain implications of governance in a SOA context. The research question of the study was to identify which SOA governance mechanisms do or do not provide support for different constituents of SOA. The study also contained three sub-questions; (i) Is there a difference between how SOA governance mechanisms support technical vs. non technical constituents of SOA? (ii) Is there any SOA governance mechanism that is more important than others? (iii) Is there a relation between the SOA governance mechanisms? The study was conducted using theories related to SOA and SOA governance. We identified the most academically accepted SOA governance mechanisms to test their support for different constituents of SOA. To get an holistic view of SOA, we used a SOA maturity framework to identify what the constituents of SOA really are. The support of the SOA governance mechanisms were then studied in relation to the different constituents of SOA, through interviews and observations, during a ten week internship at Scania. The results showed that as good as every SOA governance mechanism supports the constituents of SOA, although the level of support varied. In general, we found patterns separating the support for technological and non-technological constituents of SOA. The technological constituents of SOA were to a great extent provided the same support from SOA governance mechanisms, which also was true for the non-technological constituents of SOA. Interestingly, except for one SOA governance mechanism, the technological constituents of SOA and the non-technological obtained different levels of support from governance. The most important SOA governance mechanisms are the creation of standards and policies, having processes to create and enforce policies, processes for education, and establishing SOA skills and training. We can also conclude that there is a relationship between many of the SOA governance mechanisms, and that academics and practitioners therefore have to view SOA governance holistically, rather than independent governance mechanisms.
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Dlamini, Sandile Wilmoth. "A model-based service customization framework for consumer variability management in service-oriented architectures." Thesis, University of Zululand, 2014. http://hdl.handle.net/10530/1413.
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A thesis submitted to the Faculty of Science and Agriculture in fulfilment of the requirements for the Degree of Masters of Science in Computer Science in the Department of Computer Science at the University of Zululand, South Africa, 2014In today‘s service-oriented business environments, the standard Publish-Find-Bind model as embodied by the Service-Oriented Architecture (SOA) paradigm presents a new strong challenge in the consumption and applicability of services to its consumers. This is because services in SOA-based environments are not built and published for predefined consumers; rather they are advertised for potentially many unknown consumers. Thus, they could be (re) used by various anonymous consumers with varying requirements and business needs. Hence, to increase service applicability and efficiency in the consumption of services, as well as to stay relevant in today‘s global market economy, service providers are expected to provide services covering such a wide variety of demands. However, they are still faced and have to deal with a number of problems which need to be balanced. Consequently, this research work addresses the problem of how to deliver customizable software services, as a way to address and/or increase the applicability and efficiency in the consumption of software services. In particular, this research proposed a service customization framework called FreeCust, which exploits the feature modeling concepts or techniques from the Software Product Line Engineering (SPLE) discipline. The FreeCust framework as suggested in this research was constructed, validated, and evaluated through practical use case scenarios, proof-of-concept prototype implementations, experiments, and a comparative (static) analysis. This was to show its utility, technical feasibility, functional correctness, and business benefits. The evaluation and validation results demonstrated that the FreeCust approach has the potential or is appropriate for minimizing the complexities involved in consumers‘ service customization processes and increasing service applicability.
Telkom SA SOC Limited
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Sundar, Gayathri. "Design of a service-oriented dashboard." Birmingham, Ala. : University of Alabama at Birmingham, 2007. https://www.mhsl.uab.edu/dt/2007m/sundar.pdf.
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Thesis (M.S.)--University of Alabama at Birmingham, 2007.Additional advisors: David G. Green, Gary J. Grimes, John L. Hartman IV. Description based on contents viewed Feb. 5, 2008; title from title screen. Includes bibliographical references (p. 110-120).
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Remer, Sebastian. "Soziale Strukturen und Informationstechnologie : die organisatorische Bedeutung von "Service Oriented Architectures" /." Aachen : Shaker, 2009. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017620735&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Camacho, Gilberto. "Service-oriented mobility of java code in web services-based architectures." Master's thesis, Faculdade de Ciências e Tecnologia, 2010. http://hdl.handle.net/10362/5090.
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Dissertação apresentada na Faculdade de
Ciências e Tecnologias da Universidade Nova
de Lisboa para a obtenção do Grau de Mestre
em Engenharia InformáticaSoftware mobility consists of providing software components, the ability to migrate to a remote host with the purpose of interacting locally. In other words, this technology enables computations to be transferred from the current machine to a remote one. This powerful enhancement embodied in a traditional network fairly raises security concerns. For now, we believe that software mobility paradigm is confined to environments with bases of trust such as local area networks or middleware layers where security issues can be better controlled. Service-oriented computations reorganize the network architecture in the form of services, where components are more easily integrated, modified and removed. They have the ability to cooperate between them regardless the programming language used in their development. In addition, service-oriented computing is a widely accepted technology for the implementation of distributed applications, namely middleware. The work developed in this thesis consists of instantiating a model which combines software mobility and service-oriented paradigms as proposed by Paulino [20]. In this model, migrating sessions take advantage of the resources of a service-oriented network, creating thus an environment where the migration is modeled in terms of services instead of network nodes abstractions. In the instantiated model, we aim to apply the migration of Java programs in a context of a service-oriented architecture developed with Web services. This application comprises of a middleware layer that runs between the source program and the Web services technologies, and whose interface is the result of the mapping of the operations defined in the model. The evaluation performed to the instantiated model allows us to identify situations in which component migration to the server to interact locally is more advantageous in comparison to remote interacting with it.
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Hilburn, Benjamin Cantrell. "Component-Based Design and Service-Oriented Architectures in Software-Defined Radio." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/31985.
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Software-Defined Radio (SDR) is a large field of research, and is rapidly expanding in terms of capabilities and applications. As the number of SDR platforms, deployments, and use-cases grow, interoperability, compatibility, and software re-use becomes more difficult. Additionally, advanced SDR applications require more advanced hardware and software platforms to support them, necessitating intelligent management of resources and functionality. Realizing these goals can be done using the paradigms of Component-Based Design (CBD) and Service-Oriented Architectures (SOAs).
Component-based design has been applied to the field of SDR in the past to varying levels of success. We discuss the benefits of CBD, and how to successfully use CBD for SDR. We assert that by strictly enforcing the principles of CBD, we can achieve a high level of independence from both the hardware and software platforms, and enable component compatibility and interoperability between SDR platforms and deployments. Using CBD, we also achieve the use-case of a fully distributed SDR, where multiple hardware nodes act as one cohesive radio unit.
Applying the concept of service-orientation to SDR is a novel idea, and we discuss how this enables a new radio paradigm in the form of goal-oriented autonomic radios. We define SOAs in the context of SDR, explain how our vision is different than middle-wares like CORBA, describe how SOAs can be used, and discuss the possibilities of autonomic radio systems.
This thesis also presents our work on the Cognitive Radio Open Source Systems (CROSS) project. CROSS is a free and open-source prototype architecture that uses CBD to achieve platform independence and distributed SDR deployments. CROSS also provides an experimental system for using SOAs in SDRs. Using our reference implementation of CROSS, we successfully demonstrated a distributed cognitive radio performing dynamic spectrum access to communicate with another SDR while avoiding an interferer operating in the spectrum.Master of Science
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Remer, Sebastian. "Soziale Strukturen und Informationstechnologie die organisatorische Bedeutung von "Service oriented architectures"." Phd thesis, Aachen Shaker, 2008. http://d-nb.info/994550448/04.
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Medeiros, Flávio Mota. "SOPLE-DE: an approach to design service-oriented product line architectures." Universidade Federal de Pernambuco, 2010. https://repositorio.ufpe.br/handle/123456789/2416.
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Previous issue date: 2010Conselho Nacional de Desenvolvimento Científico e Tecnológico
O reuso de software é um fator extremamente importante para empresas interessadas em aumentar sua produtividade, diminuir os custos e o tempo durante o desenvolvimento de sistemas e melhorar a qualidade de seus produtos e serviços. Nesse contexto, Linhas de Produto de Software (LPS) e Arquitetura Orientada a Serviços (SOA) são duas estratégias que estão atualmente recebendo uma grande atenção, tanto na área acadêmica quanto na indústria de software. Os conceitos de linhas de produto e arquitetura orientada a serviços compartilham alguns objetivos e características que podem ser usados em conjunto para aumentar as taxas de reuso de software. No entanto, para o resultado dessa junção ser otimizado, é necessário utilizar um processo de desenvolvimento bem definido. Caso contrário, a equipe de desenvolvimento poderá produzir software de maneira não sistemática, aumentando as chances de falha, o tempo e o custo de desenvolvimento. Com essa visão, esse trabalho apresenta uma abordagem para o projeto de arquiteturas para linhas de produto orientada a serviços, constituída de um conjunto de atividades e sub atividades com entradas e saídas especificadas, sendo cada uma delas realizada por um conjunto predefinido de papéis com responsabilidades definidas. Essa abordagem visa ajudar arquitetos de software a projetar arquitetura orientada a serviços para domínios específicos. Para garantir a qualidade da abordagem desenvolvida, uma pesquisa extensiva foi realizada para analisar o atual estado da arte de processos para o desenvolvimento orientado a serviços. Foram então considerados os pontos fracos e fortes dos processos estudados com o intuito de identificar e preencher as lacunas neles existentes. Por fim, essa abordagem foi validada e refinada por meio de um estudo acadêmico experimental preliminar
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Rezgui, Abdelmounaam. "Service-Oriented Sensor-Actuator Networks." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/30098.
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In this dissertation, we propose service-oriented sensor-actuator networks (SOSANETs) as a new paradigm for building the next generation of customizable, open, interoperable sensor-actuator networks. In SOSANETs, nodes expose their capabilities to applications in the form of service profiles. A node's service profile consists of a set of services (i.e., sensing and actuation capabilities) that it provides and the quality of service (QoS) parameters associated with those services (delay, accuracy, freshness, etc.). SOSANETs provide the benefits of both application-specific SANETs and generic SANETs. We first define a query model and an architecture for SOSANETs. The proposed query model offers a simple, uniform query interface whereby applications specify sensing and actuation queries independently from any specific deployment of the underlying SOSANET. We then present uRACER (Reliable Adaptive serviCe-driven Efficient Routing), a routing protocol suite for SOSANETs. uRACER consists of three routing protocols,
namely, SARP (Service-Aware Routing Protocol), CARP (Context-Aware Routing Protocol), and TARP (Trust-Aware Routing Protocol). SARP uses an efficient service-aware routing approach that aggressively reduces downstream traffic by translating service profiles into efficient paths. CARP supports QoS by dynamically adapting each node's routing behavior and service profile according to the current context of that node, i.e. number of pending queries and number and type of messages to be routed. Finally, TARP achieves high end-to-end reliability through a scalable reputation-based approach in which each node is able to locally estimate the next hop of the most reliable path to the sink. We also propose query optimization techniques that contribute to the efficient execution of queries in SOSANETs. To evaluate the proposed service-oriented architecture, we implemented TinySOA, a prototype SOSANET built on top of TinyOS with uRACER as its routing mechansim. TinySOA is designed as a set of layers with a loose interaction model that enables several cross-layer optimization options. We conducted an evaluation of TinySOA that included a comparison with TinyDB. The obtained empirical results show that TinySOA achieves significant improvements on many aspects including energy consumption, scalability, reliability and response time.Ph. D.
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Alda, Sascha. "Component based adaptation methods for service oriented peer-to-peer software architectures." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=983011907.
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Becker, Basil, Holger Giese, Stefan Neumann, and System Analysis and Modeling Group. "Correct dynamic service-oriented architectures : modeling and compositional verification with dynamic collaborations." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/3047/.
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Service-oriented modeling employs collaborations to capture the coordination of multiple roles in form of service contracts. In case of dynamic collaborations the roles may join and leave the collaboration at runtime and therefore complex structural dynamics can result, which makes it very hard to ensure their correct and safe operation. We present in this paper our approach for modeling and verifying such dynamic collaborations. Modeling is supported using a well-defined subset of UML class diagrams, behavioral rules for the structural dynamics, and UML state machines for the role behavior. To be also able to verify the resulting service-oriented systems, we extended our former results for the automated verification of systems with structural dynamics [7, 8] and developed a compositional reasoning scheme, which enables the reuse of verification results. We outline our approach using the example of autonomous vehicles that use such dynamic collaborations via ad-hoc networking to coordinate and optimize their joint behavior.Bei der Modellierung Service-orientierter Systeme werden Kollaborationen verwendet, um die Koordination mehrerer Rollen durch Service-Verträge zu beschreiben. Dynamische Kollaborationen erlauben ein Hinzufügen und Entfernen von Rollen zur Kollaboration zur Laufzeit, wodurch eine komplexe strukturelle Dynamik entstehen kann. Die automatische Analyse service-orientierter Systeme wird durch diese erheblich erschwert. In dieser Arbeit stellen wir einen Ansatz zur Modellierung und Verifikation solcher dynamischer Kollaborationen vor. Eine spezielle Untermenge der UML ermöglicht die Modellierung, wobei Klassendiagramme, Verhaltensregeln für die strukturelle Dynamik und UML Zustandsdiagramme für das Verhalten der Rollen verwendet werden. Um die Verifikation der so modellierten service-orientierten Systeme zu ermöglichen, erweiterten wir unsere früheren Ergebnisse zur Verifikation von Systemen mit struktureller Dynamik [7,8] und entwickelten einen kompositionalen Verifikationsansatz. Der entwickelte Verifikationsansatz erlaubt es Ergebnisse wiederzuverwenden. Die entwickelten Techniken werden anhand autonomer Fahrzeuge, die dynamische Kollaborationen über ad-hoc Netzwerke zur Koordination und Optimierung ihres gemeinsamen Verhaltens nutzen, exemplarisch vorgestellt.
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Chen, Zheng. "Recording process documentation in the presence of failures in service oriented architectures." Thesis, University of Southampton, 2009. https://eprints.soton.ac.uk/71951/.
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Scientific and engineering communities (e.g., chemistry, bioinformatics and engineering manufacturing) have presented unprecedented requirements for knowing the provenance of their data products, i.e., where they originated from, how they were produced and what has happened to them since creation. Without such important knowledge, scientists and engineers cannot reproduce, analyse or validate experiments and processes. Previous work has conceived a computer-based representation of a past process for determining provenance, termed process documentation. However, current provenance systems do not adequately address the problem of reliably recording process documentation in large scale environments like Service Oriented Architectures. For example, a service may not be available and network connection may be broken. In this context, reliably recording process documentation becomes challenging, given that the documentation produced in a process can be spread over multiple provenance repositories across the world. The presence of failures (specifically, the crash of provenance repositories and communication failures) may prevent process documentation from being recorded, losing the evidence that a process occurred. This would have disastrous consequences and hence is not acceptable in the domains that rely on process documentation to determine the provenance of their data products. In this thesis, we systematically analyse all situations that may occur during capturing process documentation in the event of assumed failures. We then present a novel coordinator-based protocol that is formally proved to record complete process documentation. In addition, we use graphs to intuitively represent the topology of process documentation recorded in multiple interlinked provenance repositories, which helps us to investigate the entire retrievability of distributed process documentation. Finally, we evaluate a system architecture that employs the protocol and supports practical issues such as communication, storage and performance. The results show that the system can record complete and retrievable process documentation while maintaining acceptable performance.
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Mittal, Saurabh. "DEVS Unified Process For Integrated Development and Testing of Service Oriented Architectures." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194093.
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Service Oriented Architectures (SOA) present challenges to current model-based software engineering methodologies such as Rational Unified Process (RUP). In this research effort we propose a process called DEVS Unified Process (DUNIP) that uses the DEVS formalism as a basis for automated generation of models from various requirement specifications and realization as SOA collaborative services. DEVS is inherently based on object oriented methodology and systems theory, and categorically separates the Model, the Simulator and the Experimental frame, and has been used for systems Modeling & Simulation over the years. DUNIP integrates these concepts into DEVSbased Bifurcated Model-Continuity life-cycle development methodology. The life-cycle begins by specifying the system requirements in a number of different formats such as state-based, BPMN/BPEL-based, message-based requirement specifications. DUNIP then automates the generation of DEVS models capable for distributed collaboration. The collaboration uses an XML-based DEVS Modeling Language (DEVSML) framework that provides the capability to integrate models that may be expressed in different DEVS implementation languages. The models are also made available for remote and distributed real-time execution over the SOA middleware in a manner transparent to the user. A prototype simulation framework has been implemented and is illustrated with an application to a system of collaborating military systems implemented and tested using Bifurcated Model-Continuity methodology. We also show how the Department of Defense Architecture Framework (DoDAF) can be enhanced to incorporate simulation based executable models using the DUNIP process.
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Radicke, Johannes, and Thomas Pinthal. "THE EFFECTS OF SERVICE-ORIENTED ARCHITECTURES ON COMPETITIVE ADVANTAGE : A GROUNDED THEORY APPROACH." Thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-9741.
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Müller, Jens [Verfasser], and K. [Akademischer Betreuer] Böhm. "Security Mechanisms for Workflows in Service-Oriented Architectures / Jens Müller. Betreuer: K. Böhm." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1080246142/34.
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Konnerth, Thomas Verfasser], and Sahin [Akademischer Betreuer] [Albayrak. "An Agent-Based Approach to Service-Oriented Architectures / Thomas Konnerth. Betreuer: Sahin Albayrak." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2012. http://d-nb.info/1029192782/34.
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Remer, Sebastian [Verfasser]. "Soziale Strukturen und Informationstechnologie : Die organisatorische Bedeutung von „Service Oriented Architectures“ / Sebastian Remer." Aachen : Shaker, 2009. http://d-nb.info/1156517761/34.
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Shehu, Umar Galadima. "Novel optimization schemes for service composition in the cloud using learning automata-based matrix factorization." Thesis, University of Bedfordshire, 2015. http://hdl.handle.net/10547/610618.
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Service Oriented Computing (SOC) provides a framework for the realization of loosely couple service oriented applications (SOA). Web services are central to the concept of SOC. They possess several benefits which are useful to SOA e.g. encapsulation, loose coupling and reusability. Using web services, an application can embed its functionalities within the business process of other applications. This is made possible through web service composition. Web services are composed to provide more complex functions for a service consumer in the form of a value added composite service. Currently, research into how web services can be composed to yield QoS (Quality of Service) optimal composite service has gathered significant attention. However, the number and services has risen thereby increasing the number of possible service combinations and also amplifying the impact of network on composite service performance. QoS-based service composition in the cloud addresses two important sub-problems; Prediction of network performance between web service nodes in the cloud, and QoS-based web service composition. We model the former problem as a prediction problem while the later problem is modelled as an NP-Hard optimization problem due to its complex, constrained and multi-objective nature. This thesis contributed to the prediction problem by presenting a novel learning automata-based non-negative matrix factorization algorithm (LANMF) for estimating end-to-end network latency of a composition in the cloud. LANMF encodes each web service node as an automaton which allows v it to estimate its network coordinate in such a way that prediction error is minimized. Experiments indicate that LANMF is more accurate than current approaches. The thesis also contributed to the QoS-based service composition problem by proposing four evolutionary algorithms; a network-aware genetic algorithm (INSGA), a K-mean based genetic algorithm (KNSGA), a multi-population particle swarm optimization algorithm (NMPSO), and a non-dominated sort fruit fly algorithm (NFOA). The algorithms adopt different evolutionary strategies coupled with LANMF method to search for low latency and QoSoptimal solutions. They also employ a unique constraint handling method used to penalize solutions that violate user specified QoS constraints. Experiments demonstrate the efficiency and scalability of the algorithms in a large scale environment. Also the algorithms outperform other evolutionary algorithms in terms of optimality and calability. In addition, the thesis contributed to QoS-based web service composition in a dynamic environment. This is motivated by the ineffectiveness of the four proposed algorithms in a dynamically hanging QoS environment such as a real world scenario. Hence, we propose a new cellular automata-based genetic algorithm (CellGA) to address the issue. Experimental results show the effectiveness of CellGA in solving QoS-based service composition in dynamic QoS environment.
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Baltrusch, Rob. "Hybrid Multiagent Systems: Intelligent Agile Oriented Architectures for Enterprise Integration." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/366265.
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This research defines the business requirements for forming a Network capable of instantiating Virtual Enterprises (VEs); investigates the current state of the art for enterprise and Information and Communication Technology (ICT) architectures; and develops an improved intelligent software architecture for managing a dynamic, VE-forming Network of Partners. What is lacking in the current body of knowledge are methodologies and reusable partial models for how to specify and design ICT architectures that support complex coordination in an agile and intelligent manner. There is no generic method or comprehensive architecture today which would give businesses the ability to build and maintain such collaboration in a dynamically changing virtual enterprise. This problem is particularly evident in one-of-a-kind production, because the VEs must be created every time a large project is undertaken. Enterprises need to remain competitive by developing products which are specific to individual requirements, and developed globally to leverage resources. This research proposes that an enterprise can be represented as a set of hybrid, flexible, autonomous agents which encapsulate decision centres and other resources in order to execute business functions. The goal of this research is to define and develop an improved software architecture which supports globally distributed functional and resource management. The proposed ICT architecture will be developed and demonstrated using state-of-the-art protocols and platforms. The focus is on supporting: intelligent and agile interaction with customers and other Network stakeholders optimisation of the supply chain through collaboration and reasoning integrating heterogenous information and human activity systems The research objectives are to answer the following questions: 1. What are the business requirements, design parameters and design constraints for managing a dynamic, VE-forming Network of Partners? 2. Based on this design space, how can suitable supporting software architectures be specified? 3. Is the developed hypothesis valid? The fundamental research hypotheses are: 1. a VE-forming Network of Partners can be designed as a multiagent system of hybrid agents 2. such a design can be implemented using current protocols and platforms The research specifies and validates the architectural design of the Agile-Oriented Architecture, which contains several important design attributes currently not present in any of the current ICT architectures.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Information and Communication Technology
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Fredj, Manel. "Reconfiguration dynamique des architectures orientées services." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00491041.
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Azam, Nabeel A. "A Framework for Grid-Enabling Scientific Workflow Systems. Architecture and application case studies on interoperability and heterogeneity in support for Grid workflow automation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5442.
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Since the early 2000s, Service Oriented Architectures (SOAs) have played a key role in the development of complex applications within a virtual organization (VO) context. Grids and workflows have emerged as vital technologies for addressing the (SOA) paradigm. Given the variety of Grid middleware, scientific workflow systems and Grid workflows available, bringing the two technologies together in a flexible, reusable and generalized way has been largely overlooked, particularly from a scientific end user perspective. The lack of domain focus in this area has led to a slow uptake of Grid technologies.
This thesis aims to design a framework for Grid-enabling workflows, which identifies the essential technological components, how these components fit together in layered architecture and the interactions between them. To produce such a framework, this thesis first investigates the definition of a Grid-workflow architecture and mapping Grid functionality to workflow nodes, focusing on striking a balance between performance, usability and the Grid functionality supported. Next, it presents an examination of framework extensions for supporting various forms of Grid heterogeneity, essential for
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VO based collaboration. Given the complex nature of Grid technologies, the work presented here investigates abstracting Grid based workflows through high-level definitions and resolution using semantic technologies. Finally, this thesis presents a way to resolves abstract Grid workflows using semantic technologies and intelligent, autonomous agents.
The frameworks presented in this thesis are tested and evaluated within the context of domain-based case studies defined in the SIMDAT, BRIDGE and ARGUGRID EU funded research projects.
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Al-Homaimeedi, Abiar Suliman. "Specification and analysis of service oriented architectures within the calculus of communicating sequential processes (CSP)." Thesis, King's College London (University of London), 2016. http://kclpure.kcl.ac.uk/portal/en/theses/specification-and-analysis-of-service-oriented-architectures-within-the-calculus-of-communicating-sequential-processes-csp(60aa001b-c73d-430e-a084-cb903cb387b7).html.
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Software architecture evolved from the monolithic paradigm to the Service-Oriented Computing (SOC) paradigm. IT systems in the SOC paradigm are based on service compositions. A service composition is an aggregate of loosely coupled autonomous heterogeneous services which are collectively composed to implement a particular task. Internet standards are the dominant modelling methods of SOC systems. How- ever, they raise fundamental issues: standards lack formalism, and they fall short when being applied independently. The former issue has been solved and rigorous semantics have been developed for the di erent standards. However, the latter is- sue has only partially been solved, by developing new formal modelling languages that are adopting the concepts rather than the notations of the internet standards. In principle, the main concepts that should be hosted in SOC modelling languages are: asynchronicity, mobility, multiparty sessions, and compensations. However, not all of these concepts are supported in the current developed modelling languages. This thesis addresses this problem and proposes a new formal modelling language for SOC systems which is adequately expressive to model the previous concepts. Additionally, the thesis provides an implementation for the new modelling language in a model checker to facilitate automated formal reasoning on systems properties like: good/bad traces, deadlock-freedom, and livelock-freedom.
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Azam, Nabeel Adeem. "A framework for grid-enabling scientific workflow systems : architecture and application case studies on interoperability and heterogeneity in support for grid workflow automation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5442.
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Since the early 2000s, Service Oriented Architectures (SOAs) have played a key role in the development of complex applications within a virtual organization (VO) context. Grids and workflows have emerged as vital technologies for addressing the (SOA) paradigm. Given the variety of Grid middleware, scientific workflow systems and Grid workflows available, bringing the two technologies together in a flexible, reusable and generalized way has been largely overlooked, particularly from a scientific end user perspective. The lack of domain focus in this area has led to a slow uptake of Grid technologies. This thesis aims to design a framework for Grid-enabling workflows, which identifies the essential technological components, how these components fit together in layered architecture and the interactions between them. To produce such a framework, this thesis first investigates the definition of a Grid-workflow architecture and mapping Grid functionality to workflow nodes, focusing on striking a balance between performance, usability and the Grid functionality supported. Next, it presents an examination of framework extensions for supporting various forms of Grid heterogeneity, essential for ii VO based collaboration. Given the complex nature of Grid technologies, the work presented here investigates abstracting Grid based workflows through high-level definitions and resolution using semantic technologies. Finally, this thesis presents a way to resolves abstract Grid workflows using semantic technologies and intelligent, autonomous agents. The frameworks presented in this thesis are tested and evaluated within the context of domain-based case studies defined in the SIMDAT, BRIDGE and ARGUGRID EU funded research projects.
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Cabanillas, Macias Cristina, Anne Baumgrass, and Ciccio Claudio Di. "A Conceptual Architecture for an Event-based Information Aggregation Engine in Smart Logistics." Gesellschaft für Informatik e.V, 2015. https://dl.gi.de/handle/20.500.12116/2040.
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The field of Smart Logistics is attracting interest in several areas of research, including Business Process Management. Awide range of research works are carried out to enhance the capability of monitoring the execution of ongoing logistics processes and predict their likely evolvement. In order to do this, it is crucial to have in place an IT infrastructure that provides the capability of automatically intercepting the digitalised transportation-related events stemming from widespread sources, along with their elaboration, interpretation and dispatching. In this context, we present here the service-oriented software architecture of such an event-based information engine. In particular, we describe the requisites that it must meet. Thereafter, we present the interfaces and subsequently the service-oriented components that are in charge of realising them. The outlined architecture is being utilised as the reference model for an ongoing European research project on Smart Logistics, namely GET Service.
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Tupe, Sameer Vijay. "A Cognitively Inspired Architecture for Wireless Sensor Networks: A Web Service Oriented Middleware for a Traffic Monitoring System." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33624.
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We describe CoSMo, a Cognitively Inspired Service and Model Architecture for situational awareness and monitoring of vehicular traffic in urban transportation systems using a network of wireless sensors. The system architecture combines (i) a cognitively inspired internal representation for analyzing and answering queries concerning the observed system and (ii) a service oriented architecture that facilitates interaction among individual modules, of the internal representation, the observed system and the user. The cognitively inspired model architecture allows one to effectively respond to deductive as well as inductive queries by combining simulation based dynamic models with traditional relational databases. On the other hand the service oriented design of interaction allows one to build flexible, extensible and scalable systems that can be deployed in practical settings. To illustrate our concepts and the novel features of our architecture, we have recently completed a prototype implementation of CoSMo. The prototype illustrates advantages of our approach over other traditional approaches for designing scalable software for situational awareness in large complex systems. The basic architecture and its prototype implementation are generic and can be applied for monitoring other complex systems. CoSMo's architecture has a number of features that distinguish cognitive systems. This includes: dynamic internal models of the observed system, inductive and deductive learning and reasoning, perception, memory and adaptation.
This thesis describes the service oriented model and the associated prototype implementation. Two important contributions of this thesis include the following:
- The Generic Service Architecture - CoSMo's service architecture is generic and can be applied to many other application domains without much change in underlying infrastructure.
- Integration of emerging web technologies - Use of Web Services, UPnP, UDDI and many other emerging technologies have taken CoSMo beyond a prototype implementation and towards a real production system.
Master of Science
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Alzaghoul, Esra Fawaz Ahmad. "Value- and debt-aware selection and composition in cloud-based service-oriented architectures using real options." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/6350/.
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This thesis presents a novel model for service selection and composition in Cloud-based Service-Oriented Architectures (CB-SOA), which is called CloudMTD, using real options, Dependency Structure Matrix (DSM) and propagation-cost metrics. CB-SOA architectures are composed of web services, which are leased or bought off the cloud marketplace. CB-SOA can improve its utility and add value to its composition by substituting its constituent services. The substitution decisions may introduce technical debt, which needs to be managed. The thesis defines the concept of technical debt for CB-SOA and reports on the available technical debt definitions and approaches in the literature. The formulation of service substitution problem and its technical debt valuation is based on options, which exploits Binomial Options Analysis. This thesis looks at different option types under uncertainty. This thesis is concerned with some scenarios that may lead to technical debt, which are related to web service selection and composition that has been driven by either a technical or a business objective. In each scenario, we are interested in three decisions (1) keep, (2) substitute or (3) abandon the current service. Each scenario takes into consideration either one or more QoS attribute dimension (e.g. Availability). We address these scenarios from an option-based perspective. Each scenario is linked to a suitable option type. A specific option type depends on the nature of the application, problem to be investigated, and the decision to be taken. In addition, we use Dependency Structure Matrix (DSM) in order to represent dependencies among web services in CB-SOA. We introduce time and complexity sensitive propagation-cost metrics to DSM to solve the problem. In addition, CloudMTD model informs the time-value of the decisions under uncertainty based on behavioral and structural aspects of CB-SOA.
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Weindelmayer, Frederick J. "An experimental study of the suitability of Java Web services for real-time service oriented architectures." Ann Arbor, Mich. : ProQuest, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1450593.
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Thesis (M.S. in Software Engineering)--S.M.U.Title from PDF title page (viewed Mar. 16, 2009). Source: Masters Abstracts International, Volume: 46-05, page: 2736. Adviser: Frank Coyle. Includes bibliographical references.
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Cancela, Paulo Filipe Neves Bento. "Orchestration of heterogeneous middleware services and its application to a comand and control platform." Master's thesis, FCT - UNL, 2009. http://hdl.handle.net/10362/1970.
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MSC Dissertation in Computer EngineeringDistributed objects was, until recently, the leading technology in the design and implementation of component-based architectures, such as the ones based on services, better known as Service-Oriented Architectures (SOA). Although established in the market for more than a decade, and therefore mature, these technologies have failed to overcome the porting of the SOA concept to the Web. Web services are a recent technology that has been growing in the last few years. Their acceptance has increased over enterprises and organizations as they seem to overcome the Web and interoperability related problems of the Distributed Objects technology. Web services provide interoperability between systems and that is undoubtedly a strength of this technology since this is a crucial aspect of nowadays business. Moreover, the widespread of services led to the recent introduction of the service composition concept, that although being a technology independent concept,is closely related to Web services and there is no tool support for other technologies. Nonetheless, distributed objects still play an important role in the development of distributed systems, namely due to performance issues that are important when it comes to the internals of a platform. However, the use of service composition in these distributed object-based platforms requires the exposure of their composing services as Web services. The main objective of this masters thesis is improve the state-of-the-art in the support for the composition of services originating from distributed objects-based platforms. Bearing in mind that these kind of platforms are composed by several services, the idea is to present a platform as a set of Web services in order to be able to orchestrate them.
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Kaur, Navjot. "A service-oriented approach to embedded component-based manufacturing automation." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/9445.
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This thesis is focused on the application of Component-Based (CB) technology to shop floor devices using a Service Oriented Architecture (SOA) and Web Services (WS) for the purpose of realising future generation agile manufacturing systems. The environment of manufacturing enterprises is now characterised by frequently changing market demands, time-to-market pressure, continuously emerging new technologies and global competition. Under these circumstances, manufacturing systems need to be agile and automation systems need to support this agility. More specifically, an open, exible automation environment with plug and play connectivity is needed. Technically, this requires the easy connectivity of hardware devices and software components from different vendors. Functionally, there is a need of interoperability and integration of control functions on different hierarchical levels ranging from field level to various higher level applications such as process control and operations management services. A potential solution is to realise a modular and reconfigurable automation system, based on a platform of reusable components; while simultaneously reducing the number of unique components. For designing such reusable components, a component-based technology has been used in current thesis. The automation components created are active and distributed entities interacting through their data, event and service ports. To communicate these entities, this thesis focuses on applying SOA and WS at device level. SOA and WS have already been proven successful in linking business applications. If SOA can be applied at shop floor using the embedded devices, it can enable entirely new automation architecture based on peer-to-peer interactions between autonomous devices. The adoption of this SOA-WS approach at shop floor level would enable a seamless integration of higher level business applications and shop- floor level system. This will also provide a loosely coupled message-oriented service in embedded device networks and geographically distributed automation system. SOA can be implemented using Web Services on the embedded devices, which will provide even greater exibility and interoperability because WS is platform neutral. This SOA-WS approach will enable end users to operate and maintain the supplied system easily. A key aim of this thesis is to examine if the adoption of SOA-WS at the embedded control devices can provide the same level of message speed and reliability as the current control systems. It is expected that the desired distributed, loosely coupled and reconfigurable automation system can be formed by a network of these collaborative autonomous SOA-WS based devices using an open control platform. This approach has been experimentally evaluated both in terms of quantity and quality using various parameters involved in the design, implementation, evaluation and recon guration of SOA-WS based automation systems. This has been done using the Ford Festo test rig located at the Manufacturing System Integration Research Institute of Loughborough University. The mechanisms on this test rig represent control problems typically associated in engine assembly and handling machines. Therefore, the result of experimental studies performed on this test rig can be considered applicable to real manufacturing applications.
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Dinkel, Stephen Carl. "Reasoning for Service-based Situational Awareness Information on the Semantic Web." NSUWorks, 2012. http://nsuworks.nova.edu/gscis_etd/134.
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Accurate situational assessment is key to any decision maker and especially crucial in military command and control, air traffic control, and complex system decision making. Endsley described three dependent levels of situational awareness, (1) perception, (2) understanding, and (3) projection. This research was focused on Endsley's second-level situational awareness (understanding) as it applies to service-oriented information technology environments in the context of the Semantic Web. Specifically, this research addressed the problem of developing accurate situational assessments related to the status or health of information technology (IT) services, especially composite, dynamic IT services, when some of Endsley's first level (perceived) information was inaccurate or incomplete.
Research had not adequately addressed the problem of how to work with inaccuracy and situational awareness information in order to produce accurate situational assessments for Semantic Web services. This problem becomes especially important as the current Web moves towards a Semantic Web where information technology is expected to be represented and processed by machines. Costa's probabilistic Web ontology language (PR-OWL), as extended by Carvalho (PR-OWL2), is a framework for storage of and reasoning with uncertainty information as part of the Semantic Web.
This study used Costa's PR-OWL framework, as extended by Carvalho, to build an ontology that supports reasoning with service-oriented information in the context of the Semantic Web and then assessed the effectiveness of the developed ontology through the use of competency questions, as described by Gruninger and Fox and verified through the use of an automated reasoner. This research resulted in a Web Ontology Language for Services (OWL-S), PR-OWL2 based ontology, and its associated Multi-Entity Bayesian Network which are flexible and highly effective in calculating situational assessments through the propagation of posterior probabilities using Bayesian logic.
Specifically, this research (1) identifies sufficient information required for effective situational awareness reasoning, (2) specifies the predicates and semantics necessary to represent service components and dependencies, (3) applies Multi-Entity Bayesian Network to reason with situational awareness information, (4) ensures the correctness and consistency of the situational awareness ontology, and (5) accurately estimates posterior probabilities consistent with situational awareness information.
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Barnickel, Nils [Verfasser], and Radu [Akademischer Betreuer] Popescu-Zeletin. "Semantic Mediation between Loosely Coupled Information Models in Service-Oriented Architectures / Nils Barnickel. Betreuer: Radu Popescu-Zeletin." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2011. http://d-nb.info/1014891353/34.
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Khan, Zaheer Abbas. "Bridging the gap between business process models and service oriented architectures with reference to the grid environment." Thesis, University of the West of England, Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501099.
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Business process modelling is the process of visualising business processes in order to understand, improve and/or enact these processes in a particular computing environment. Furthermore, it is envisaged that environments that adopt the Service Oriented Architecture (SOA) model of computing are increasingly becoming the de facto environment for executing business processes represented by their visual models. However, it is not possible to use application domain specific web or grid services to enact or execute business processes without translating them into executable programmes. This suggests the need for a generic approach to perform these translations in a structured manner. This research is an attempt to bridge the gap between business process models and service-oriented environments with reference to RAD (Role Activity Diagramming) business process models and grid-aware service-oriented environments.
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Siddiqui, Abbas [Verfasser], Paul [Akademischer Betreuer] Müller, and Andreas [Akademischer Betreuer] Mitschele-Thiel. "Requirements-Aware, Template-Based Protocol Graphs for Service-Oriented Network Architectures / Abbas Siddiqui ; Paul Müller, Andreas Mitschele-Thiel." Kaiserslautern : Technische Universität Kaiserslautern, 2016. http://d-nb.info/1122438613/34.
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Siddiqui, Abbas Verfasser], Paul [Akademischer Betreuer] Müller, and Andreas [Akademischer Betreuer] [Mitschele-Thiel. "Requirements-Aware, Template-Based Protocol Graphs for Service-Oriented Network Architectures / Abbas Siddiqui ; Paul Müller, Andreas Mitschele-Thiel." Kaiserslautern : Technische Universität Kaiserslautern, 2016. http://nbn-resolving.de/urn:nbn:de:hbz:386-kluedo-45242.
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Martín, de Pozuelo Genís Ramon. "Application of service composition mechanisms to Future Networks architectures and Smart Grids." Doctoral thesis, Universitat Ramon Llull, 2017. http://hdl.handle.net/10803/399992.
Full textAbstract:
Aquesta tesi gira entorn de la hipòtesi de la metodologia i mecanismes de composició de serveis i com es poden aplicar a diferents camps d'aplicació per a orquestrar de manera eficient comunicacions i processos flexibles i sensibles al context. Més concretament, se centra en dos camps d'aplicació: la distribució eficient i sensible al context de contingut multimèdia i els serveis d'una xarxa elèctrica intel·ligent. En aquest últim camp es centra en la gestió de la infraestructura, cap a la definició d'una Software Defined Utility (SDU), que proposa una nova manera de gestionar la Smart Grid amb un enfocament basat en programari, que permeti un funcionament molt més flexible de la infraestructura de xarxa elèctrica. Per tant, revisa el context, els requisits i els reptes, així com els enfocaments de la composició de serveis per a aquests camps. Fa especial èmfasi en la combinació de la composició de serveis amb arquitectures Future Network (FN), presentant una proposta de FN orientada a serveis per crear comunicacions adaptades i sota demanda. També es presenten metodologies i mecanismes de composició de serveis per operar sobre aquesta arquitectura, i posteriorment, es proposa el seu ús (en conjunció o no amb l'arquitectura FN) en els dos camps d'estudi. Finalment, es presenta la investigació i desenvolupament realitzat en l'àmbit de les xarxes intel·ligents, proposant diverses parts de la infraestructura SDU amb exemples d'aplicació de composició de serveis per dissenyar seguretat dinàmica i flexible o l'orquestració i gestió de serveis i recursos dins la infraestructura de l'empresa elèctrica.Esta tesis gira en torno a la hipótesis de la metodología y mecanismos de composición de servicios y cómo se pueden aplicar a diferentes campos de aplicación para orquestar de manera eficiente comunicaciones y procesos flexibles y sensibles al contexto. Más concretamente, se centra en dos campos de aplicación: la distribución eficiente y sensible al contexto de contenido multimedia y los servicios de una red eléctrica inteligente. En este último campo se centra en la gestión de la infraestructura, hacia la definición de una Software Defined Utility (SDU), que propone una nueva forma de gestionar la Smart Grid con un enfoque basado en software, que permita un funcionamiento mucho más flexible de la infraestructura de red eléctrica. Por lo tanto, revisa el contexto, los requisitos y los retos, así como los enfoques de la composición de servicios para estos campos. Hace especial hincapié en la combinación de la composición de servicios con arquitecturas Future Network (FN), presentando una propuesta de FN orientada a servicios para crear comunicaciones adaptadas y bajo demanda. También se presentan metodologías y mecanismos de composición de servicios para operar sobre esta arquitectura, y posteriormente, se propone su uso (en conjunción o no con la arquitectura FN) en los dos campos de estudio. Por último, se presenta la investigación y desarrollo realizado en el ámbito de las redes inteligentes, proponiendo varias partes de la infraestructura SDU con ejemplos de aplicación de composición de servicios para diseñar seguridad dinámica y flexible o la orquestación y gestión de servicios y recursos dentro de la infraestructura de la empresa eléctrica.
This thesis revolves around the hypothesis the service composition methodology and mechanisms and how they can be applied to different fields of application in order to efficiently orchestrate flexible and context-aware communications and processes. More concretely, it focuses on two fields of application that are the context-aware media distribution and smart grid services and infrastructure management, towards a definition of a Software-Defined Utility (SDU), which proposes a new way of managing the Smart Grid following a software-based approach that enable a much more flexible operation of the power infrastructure. Hence, it reviews the context, requirements and challenges of these fields, as well as the service composition approaches. It makes special emphasis on the combination of service composition with Future Network (FN) architectures, presenting a service-oriented FN proposal for creating context-aware on-demand communication services. Service composition methodology and mechanisms are also presented in order to operate over this architecture, and afterwards, proposed for their usage (in conjunction or not with the FN architecture) in the deployment of context-aware media distribution and Smart Grids. Finally, the research and development done in the field of Smart Grids is depicted, proposing several parts of the SDU infrastructure, with examples of service composition application for designing dynamic and flexible security for smart metering or the orchestration and management of services and data resources within the utility infrastructure.
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Menzel, Michael. "Model-driven security in service-oriented architectures : leveraging security patterns to transform high-level security requirements to technical policies." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2012/5905/.
Full textAbstract:
Service-oriented Architectures (SOA) facilitate the provision and orchestration of business services to enable a faster adoption to changing business demands. Web Services provide a technical foundation to implement this paradigm on the basis of XML-messaging. However, the enhanced flexibility of message-based systems comes along with new threats and risks. To face these issues, a variety of security mechanisms and approaches is supported by the Web Service specifications. The usage of these security mechanisms and protocols is configured by stating security requirements in security policies. However, security policy languages for SOA are complex and difficult to create due to the expressiveness of these languages.
To facilitate and simplify the creation of security policies, this thesis presents a model-driven approach that enables the generation of complex security policies on the basis of simple security intentions. SOA architects can specify these intentions in system design models and are not required to deal with complex technical security concepts.
The approach introduced in this thesis enables the enhancement of any system design modelling languages – for example FMC or BPMN – with security modelling elements. The syntax, semantics, and notion of these elements is defined by our security modelling language SecureSOA. The metamodel of this language provides extension points to enable the integration into system design modelling languages. In particular, this thesis demonstrates the enhancement of FMC block diagrams with SecureSOA.
To enable the model-driven generation of security policies, a domain-independent policy model is introduced in this thesis. This model provides an abstraction layer for security policies. Mappings are used to perform the transformation from our model to security policy languages.
However, expert knowledge is required to generate instances of this model on the basis of simple security intentions. Appropriate security mechanisms, protocols and options must be chosen and combined to fulfil these security intentions. In this thesis, a formalised system of security patterns is used to represent this knowledge and to enable an automated transformation process. Moreover, a domain-specific language is introduced to state security patterns in an accessible way. On the basis of this language, a system of security configuration patterns is provided to transform security intentions related to data protection and identity management. The formal semantics of the security pattern language enable the verification of the transformation process introduced in this thesis and prove the correctness of the pattern application.
Finally, our SOA Security LAB is presented that demonstrates the application of our model-driven approach to facilitate a dynamic creation, configuration, and execution of secure Web Service-based composed applications.Im Bereich der Enterprisearchitekturen hat das Paradigma der Service-orientierten Architektur (SOA) in den vergangenen Jahren eine große Bedeutung erlangt. Dieser Ansatz ermöglicht die Strukturierung und Umsetzung verteilter, IT-basierter Geschäftsfunktionen, um einen effizienten und flexiblen Einsatz von IT-Ressourcen zu ermöglichen. Während in der Vergangenheit fachliche Anforderungen in monolithischen Applikationen umgesetzt wurden, setzt dieser Architekturansatz auf wiederverwendbare Dienste, die spezifische Geschäftsfunktionen implementieren. Diese Dienste können dann dynamisch zur Umsetzung von Geschäftsprozessen herangezogen werden und ermöglichen eine schnelle Reaktion auf verändernde geschäftliche Rahmenbedingungen durch Anpassung der Prozesse. Die einzelnen Dienste existieren unabhängig voneinander und sind lose über einen Nachrichtenaustausch gekoppelt. Diese Unabhängigkeit unterscheidet den SOA-Ansatz von der bisherigen Entwicklung klassischer verteilter Anwendungen. Die Verwendung unabhängiger Dienste geht aber auch mit einem größeren Gefährdungspotential einher, da eine Vielzahl von Schnittstellen bereitgestellt wird, die mittels komplexer Protokolle angesprochen werden können. Somit ist die korrekte Umsetzung von Sicherheitsmechanismen in allen Diensten und SOA-Infrastrukturkomponeten essentiell. Kommunikationspartner müssen an jedem Kommunikationsendpunkt authentifiziert und autorisiert werden und ausgetauschte Nachrichten müssen immer geschützt werden. Solche Sicherheitsanforderungen werden in technischen Sicherheitskonfigurationen (Policydokumenten) mittels einer Policysprache kodiert und werden an die Dienste verteilt, die diese Anforderungen durchsetzen. Da Policysprachen für SOA aber durch die Vielzahl und Vielfalt an Sicherheitsmechanismen, -protokollen und -standards eine hohe Komplexität aufweisen, sind Sicherheitskonfigurationen höchst fehleranfällig und mit viel Fachwissen zu erstellen. Um die Generierung von Sicherheitskonfigurationen in komplexen Systemen zu vereinfachen, wird in dieser Arbeit ein modellgetriebener Ansatz vorgestellt, der eine visuelle Modellierung von Sicherheitsanforderungen in Architekturmodellen ermöglicht und eine automatisierte Generierung von Sicherheitskonfigurationen auf Basis dieser Anforderungen unterstützt. Die Modellierungsebene ermöglicht eine einfache und abstrakte Darstellung von Sicherheitsanforderungen, die sich auch für Systemarchitekten erschließen, welche keine Sicherheits-experten sind. Beispielsweise können modellierte Daten einfach mit einem Schloss annotiert werden, um den Schutz dieser Daten zu fordern. Die Syntax, die Semantik und die Darstellung dieser Anforderungen werden durch die in dieser Arbeit vorgestellte Sicherheitsmodellierungssprache SecureSOA spezifiziert. Der vorgestellte modellgetriebene Ansatz transformiert die modellierten Anforderungen auf ein domänen-unabhängiges Policymodell, das eine Abstraktionsschicht zu konkreten Policysprachen bildet. Diese Abstrak-tionsschicht vereinfacht die Generierung von Sicherheitspolicies in verschiedenen Policysprachen. Allerdings kann diese Transformation nur erfolgen, wenn im System Expertenwissen hinterlegt ist, das die Auswahl von konkreten Sicherheitsmechanismen und -optionen bestimmt. Im Rahmen dieser Arbeit werden Entwurfsmuster für SOA-Sicherheit zur Transformation herangezogen, die dieses Wissen repräsentieren. Dazu wird ein Katalog von Entwurfsmustern eingeführt, der die Abbildung von abstrakten Sicherheitsanforderungen auf konkrete Konfigurationen ermöglicht. Diese Muster sind mittels einer Entwurfsmustersprache definiert, die in dieser Arbeit eingeführt wird. Die formale Semantik dieser Sprache ermöglicht die formale Verifikation des Transformationsprozesses, um die Korrektheit der Entwurfsmusteranwendung nachzuweisen. Die Definition dieses Entwurfsmusterkatalogs und der darauf basierende Transformationsprozess ermöglichen die Abbildung von abstrakten Sicherheitsanforderungen auf konkrete technische Sicherheitskonfigurationen und stellen den Beitrag dieser Arbeit dar. Abschließend wird in dieser Arbeit das SOA-Security-Lab vorgestellt, das die Umsetzung dieses Ansatzes demonstriert.
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Both, Andreas [Verfasser], Wolf [Akademischer Betreuer] Zimmermann, and H. W. [Akademischer Betreuer] Schmidt. "Protocol conformance checking of component-based systems and service-oriented architectures / Andreas Both. Betreuer: Wolf Zimmermann ; H. W. Schmidt." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2010. http://d-nb.info/1024975665/34.
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BRANCA, GIOVANNI. "Architectures and technologies for quality of service provisioning in next generation networks." Doctoral thesis, Università degli Studi di Cagliari, 2012. http://hdl.handle.net/11584/266146.
Full textAbstract:
A NGN is a telecommunication network that differs from classical dedicated networks because of its capability to provide voice, video, data and cellular services on
the same infrastructure (Quadruple-Play). The ITU-T standardization body has defined the NGN architecture in three different and well-defined strata: the transport stratum which takes care of maintaining end-to-end connectivity, the service stratum that is responsible for enabling the creation and the delivery of services, and finally the application stratum where applications can be created and executed. The most important separation in this architecture is relative to transport and service stratum. The aim is to enable the flexibility to add, maintain and remove services without any impact on the transport layer; to enable the flexibility to add, maintain and remove transport technologies without any impact on the access to service, application, content and information; and finally the efficient cohesistence of multiple terminals, access
technologies and core transport technologies. The Service Oriented Architecture (SOA) is a paradigm often used in systems deployment and integration for organizing and utilizing distributed capabilities under the control of different ownership domains. In this thesis, the SOA technologies in network architetures are surveyed following the NGN functional architecture as defined by the ITU-T. Within each stratum, the main logical functions that
have been the subject of investigation according to a service-oriented approach have been highlighted. Moreover, a new definition of the NGN transport stratum functionalities according to the SOA paradigm is proposed; an implementation of the relevant services interfaces to analyze this approach with experimental results shows some insight on the potentialities of the proposed strategy.
Within NGN architectures research topic, especially in IP-based network architectures, Traffic Engineering (TE) is referred to as a set of policies and algorithms
aimed at balancing network traffic load so as to improve network resource utilization and guarantee the service specific end-to-end QoS. DS-TE technology extends TE
functionalities to a per-class basis implementation by introducing a higher level of traffic classification which associates to each class type (CT) a constraint on bandwidth
utilization. These constraints are set by defining and configuring a bandwidth constraint (BC) model whih drives resource utilization aiming to higher load balancing, higher QoS performance and lower call blocking rate. Default TE implementations relies on a centralized approach to bandwidth and routing management, that require external
management entities which periodically collect network status information and provide management actions. However, due to increasing network complexity, it is desiderable
that nodes automatically discover their environment, self-configure and update to adapt to changes. In this thesis the bandwidth management problem is approached adopting an autonomic and distributed approach. Each node has a self-management module, which monitors the unreserved bandwidth in adjacent nodes and adjusts the local bandwidth
constraints so as to reduce the differences in the unreserved bandwidth of neighbor nodes. With this distributed and autonomic algorithm, BC are dinamically modified to drive routing decision toward the traffic balancing respecting the QoS constraints for each
class-type traffic requests. Finally, Video on Demand (VoD) is a service that provides a video whenever the
customer requests it. Realizing a VoD system by means of the Internet network requires architectures tailored to video features such as guaranteed bandwidths and constrained
transmission delays: these are hard to be provided in the traditional Internet architecture that is not designed to provide an adequate quality of service (QoS) and quality of
experience (QoE) to the final user. Typical VoD solutions can be grouped in four categories: centralized, proxy-based, Content Delivery Network(CDN) and Hybrid
architectures. Hybrid architectures combine the employment of a centralized server with that of a Peer-to-peer (P2P) network. This approach can effectively reduce the server load and avoid network congestions close to the server site because the peers support the delivery of the video to other peers using a cache-and-relay strategy making use of their upload bandwidth. Anyway, in a peer-to-peer network each peer is free to join and leave the network without notice, bringing to the phenomena of peer churns. These dynamics are dangerous for VoD architectures, affecting the integrity and retainability of the service. In this thesis, a study aimed to evaluate the impact of the peer churn on the system performance is proposed. Starting from important relationships between system parameters such as playback buffer length, peer request rate, peer average lifetime and
server upload rate, four different analytic models are proposed.