Dissertations / Theses on the topic 'Web Service'
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McElhiney, Patrick R. "Scalable Web Service Development with Amazon Web Services." Thesis, University of New Hampshire, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10931435.
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The objective of this thesis was to explore the topic of scalable web development, and it answered the question, “How do you scale a website to handle more traffic at peak times without wasting resources?” This is important research to any web company that has issues with rising costs as demand for their website increases. It would be wise for every online business to be prepared for more web traffic, before it occurs, without spending the budget of a multi-million user web company in low traffic periods. The last thing you want is an error as your customer base starts to arrive, giving them a bad experience for their first impressions, which would result in lost revenue.
Scalable software development architectures, including microservices, big data, and Kubernetes were studied, in addition to similar web service companies including Facebook, Twitter, and Match.com. A scalable architecture was designed for a social media web service, MeAndYou, using the big data configuration with a shared Aurora database, which was configured using an auto-scaling group attached to a load balancer in Amazon Web Services (AWS). It was tested using a custom threaded Selenium-based Python script that applied simulated user load to the servers. As the load was applied, AWS added more Elastic Compute Cloud (EC2) instances running a virtual disk image of the web server. After the load was removed, the instances were terminated automatically by AWS to save costs.
Countless steps were taken to make the web service bigger and more scalable than it originally was, before testing, including adding more fields to user profiles, adding more search types, and separating the layers of code into different Hypertext Preprocessor (PHP) files in the front-end. A version control system was configured on the servers using GitHub and rsync. The systems architecture designed suggests the Match Engine should use a stream processing message queue, which would allow the system to factor searches one at a time as they are created, with horizontal scaling capabilities, rather than grabbing the entire database and storing it in memory. The backend Match Engine was also tested for accuracy using Structured Query Language (SQL) injection, which determined how the match algorithm should be improved in the future.
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Ivanovas, Anselm. "Der Markt für Web Services Eine Analyse kommerzieller Web Service Verzeichnisse /." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/06609077001/$FILE/06609077001.pdf.
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Utku, Selma. "Web Service Testing For Domain Specific Web Service Discovery Framework." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614083/index.pdf.
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The reliability of web services is important for both users and other service providers, with which they are in interaction. Thus, to guarantee reliability of the web services that are invoked and integrated at runtime, automatic testing of web services is needed.
In web service testing, different test cases for web services are generated. The most important issue is to generate the most appropriate value for input parameters of web services at runtime. In this thesis, we developed a method for automatic web service testing that uses semantics dependency-based and data mutation-based techniques to analyze web services and generate different test cases. Thus, we both check whether the services function correctly by generating appropriate input values from different data sources and check robustness of web services by generating random and error-prone data inputs. With respect to the behaviors of web services, the test values are calculated and saved to the database for each web service.
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Zheng, George. "Web Service Mining." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/26324.
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In this dissertation, we present a novel approach for Web service mining. Web service mining is a new research discipline. It is different from conventional top down service composition approaches that are driven by specific search criteria. Web service mining starts with no such criteria and aims at the discovery of interesting and useful compositions of existing Web services. Web service mining requires the study of three main research topics: semantic description of Web services, efficient bottom up composition of composable services, and interestingness and usefulness evaluation of composed services. We first propose a Web service ontology to describe and organize the constructs of a Web service. We introduce the concept of Web service operation interface for the description of shared Web service capabilities and use Web service domains for grouping Web service capabilities based on these interfaces. We take clues from how Nature solves the problem of molecular composition and introduce the notion of Web service recognition to help devise efficient bottom up service composition strategies. We introduce several service recognition mechanisms that take advantage of the domain-based categorization of Web service capabilities and ontology-based description of operation semantics. We take clues from the drug discovery process and propose a Web service mining framework to group relevant mining activities into a progression of phases that would lead to the eventual discovery of useful compositions. Based on the composition strategies that are derived from recognition mechanisms, we propose a set of algorithms in the screening phase of the framework to automatically identify leads of service compositions. We propose objective interestingness and usefulness measures in the evaluation phase to narrow down the pool of composition leads for further exploration. To demonstrate the effectiveness of our framework and to address challenges faced by existing biological data representation methodologies, we have applied relevant techniques presented in this dissertation to the field of biological pathway discovery.Ph. D.
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Wu, Chen. "Service distribution and service discovery through a public web services platform." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/387.
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Service-Oriented Architecture (SOA) represents an emerging architectural approach that is able to tackle challenges in the contemporary service-based economy, in which the global market revenues are shifting from the manufacture of traditional off-the-shelf products to the provision of diversified services that suffice for customers’ needs. In such a service-based economy, one can envisage an entirely “service-oriented” world, where a massive number of distributed services with different natures and capabilities are provided by various professionals around the world. Problems arise when business applications demand desirable services through different sources and providers that are appropriate for their own benefits and preferences. Therefore, it can be very challenging to design an SOA infrastructure that enables users to exploit this great level of service heterogeneity and quantity. One of the key issues in service-oriented architecture is to achieve efficient service discovery and loosely-coupled service distribution while maintaining a satisfactory degree of scalability, usability, and Web consistency. This thesis deals with SOA infrastructure-level design and implementation issues. It approaches this SOA infrastructure within the scope of Web services, which capture an important, and perhaps the best, ‘realisation’ of SOA. It investigates and formulates how public Web services distributed across the World Wide Web can be augmented by a software platform that enables scalable, user-centred,semantic-enabled, and integration-oriented service retrieval, selection, and matching. The primary goal of this thesis is thus to propose a conceptual framework of an enhanced SOA infrastructure with regard to service distribution and discovery.It also aims to design and implement a platform (PWSP), by means of which a large number of public Web services on the Web can be distributed based on service demands, retrieved based on service descriptions, selected based on service qualities, and matched based on service messages in a user-centred, scalable, and Web-consistent manner without augmenting existing Web services standards.
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Wu, Chen. "Service distribution and service discovery through a public web services platform." Curtin University of Technology, Digital Ecosystems and Business Intelligence Institute, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17919.
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Service-Oriented Architecture (SOA) represents an emerging architectural approach that is able to tackle challenges in the contemporary service-based economy, in which the global market revenues are shifting from the manufacture of traditional off-the-shelf products to the provision of diversified services that suffice for customers’ needs. In such a service-based economy, one can envisage an entirely “service-oriented” world, where a massive number of distributed services with different natures and capabilities are provided by various professionals around the world. Problems arise when business applications demand desirable services through different sources and providers that are appropriate for their own benefits and preferences. Therefore, it can be very challenging to design an SOA infrastructure that enables users to exploit this great level of service heterogeneity and quantity. One of the key issues in service-oriented architecture is to achieve efficient service discovery and loosely-coupled service distribution while maintaining a satisfactory degree of scalability, usability, and Web consistency. This thesis deals with SOA infrastructure-level design and implementation issues. It approaches this SOA infrastructure within the scope of Web services, which capture an important, and perhaps the best, ‘realisation’ of SOA. It investigates and formulates how public Web services distributed across the World Wide Web can be augmented by a software platform that enables scalable, user-centred,semantic-enabled, and integration-oriented service retrieval, selection, and matching. The primary goal of this thesis is thus to propose a conceptual framework of an enhanced SOA infrastructure with regard to service distribution and discovery.It also aims to design and implement a platform (PWSP), by means of which a large number of public Web services on the Web can be distributed based on service demands, retrieved based on service descriptions, selected based on service qualities, and matched based on service messages in a user-centred, scalable, and Web-consistent manner without augmenting existing Web services standards.
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Gooneratne, Nalaka Dilshan, and s3034554@student rmit edu au. "Discovery and Validation for Composite Services on the Semantic Web." RMIT University. Computer Science and Information Technology, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091019.155524.
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Current technology for locating and validating composite services are not sufficient due to the following reasons. Current frameworks do not have the capacity to create complete service descriptions since they do not model all the functional aspects together (i.e. the purpose of a service, state transitions, data transformations). Those that deal with behavioural descriptions are unable to model the ordering constraints between concurrent interactions completely since they do not consider the time taken by interactions. Furthermore, there is no mechanism to assess the correctness of a functional description. Existing semantic-based matching techniques cannot locate services that conform to global constraints. Semantic-based techniques use ontological relationships to perform mappings between the terms in service descriptions and user requests. Therefore, unlike techniques that perform either direct string matching or schema matching, semantic-based approaches can match descriptions created with different terminologies and achieve a higher recall. Global constraints relate to restrictions on values of two or more attributes of multiple constituent services. Current techniques that generate and validate global communication models of composite services yield inaccurate results (i.e. detect phantom deadlocks or ignore actual deadlocks) since they either (i) do not support all types of interactions (i.e. only send and receive, not service and invoke) or (ii) do not consider the time taken by interactions. This thesis presents novel ideas to deal with the stated limitations. First, we propose two formalisms (WS-ALUE and WS-π-calculus) for creating functional and behavioural descriptions respectively. WS-ALUE extends the Description Logic language ALUE with some new predicates and models all the functional aspects together. WS-π-calculus extends π-calculus with Interval Time Logic (ITL) axioms. ITL axioms accurately model temporal relationships between concurrent interactions. A technique comparing a WS-π-calculus description of a service against its WS-ALUE description is introduced to detect any errors that are not equally reflected in both descriptions. We propose novel semantic-based matching techniques to locate composite services that conform to global constraints. These constraints are of two types: strictly dependent or independent. A constraint is of the former type if the values that should be assigned to all the remaining restricted attributes can be uniquely determined once a value is assigned to one. Any global constraint that is not strictly dependent is independent. A complete and correct technique that locates services that conform to strictly dependent constraints in polynomial time, is defined using a three-dimensional data cube. The proposed approach that deals with independent constraints is correct, but not complete, and is a heuristic approach. It incorporates user defined objective functions, greedy algorithms and domain rules to locate conforming services. We propose a new approach to generate global communication models (of composite services) that are free of deadlocks and synchronisation conflicts. This approach is an extension of a transitive temporal reasoning mechanism.
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Medjahed, Brahim. "Semantic Web Enabled Composition of Web Services." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/27364.
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In this dissertation, we present a novel approach for the automatic composition of Web services on the envisioned Semantic Web. Automatic service composition requires dealing with three major research thrusts: semantic description of Web services, composability of participant services, and generation of composite service descriptions.
This dissertation deals with the aforementioned research issues. We first propose an ontology-based framework for organizing and describing semantic Web services. We introduce the concept of community to cluster Web services based on their domain of interest. Each community is defined as an instance of an ontology called community ontology. We then propose a composability model to check whether semantic Web services can be combined together, hence avoiding unexpected failures at run time. The model defines formal safeguards for meaningful composition through the use of composability rules. We also introduce the notions of composability degree and tau-composability to cater for partial and total composability. Based on the composability model, we propose a set of algorithms that automatically generate detailed descriptions of composite services from high-level specifications of composition requests. We introduce a Quality of Composition (QoC) model to assess the quality of the generated composite services. The techniques presented in this dissertation are implemented in WebDG, a prototype for accessing e-government Web services. Finally, we conduct an extensive performance study (analytical and experimental) of the proposed composition algorithms.Ph. D.
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Adel, Serhani Mohamed. "A framework and methodology for managing quality of web services extending service oriented architecture: SOA to support web service management, QoWS management and web service composition management." Saarbrücken VDM Verlag Dr. Müller, 2006. http://d-nb.info/991217853/04.
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Sun, Hua. "Telephone directory web service." CSUSB ScholarWorks, 2003. https://scholarworks.lib.csusb.edu/etd-project/2421.
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Böök, Klas, and Christian Strand. "Jini kontra Web services, med intention att göra Web services pålitligt." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-58.
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Detta examensarbete behandlar Service Oriented Architecture (SOA) och dess implementeringar Jini och Web services. SOA beskriver hur applikationsintegration mellan olika plattformar skall ske och innebär att applikationer designas som tjänster för att enkelt integreras med andra applikationer. Dynamisk lokalisering av tjänster via en registertjänst används för att applikationer skall finna andra applikationer. Vi designar och implementerar en mekanism i Web services som gör det möjligt att byta en tjänst under exekvering. Ett sådant byte kan vara intressant av två skäl, tjänster kan registreras utan att vara tillgängliga, eller att det uppstår ett fel under exekvering som gör att tjänsten blir otillgänglig.
This degree project is about Service Oriented Architecture (SOA) and its implementations Jini and Web services. SOA is a description of how application integration between different platforms can be carried out by designing applications as services, which implies an easier integration with other applications. Dynamic location of services is carried out by consultation with a register service so that applications can find other applications. We design and implement a mechanism in Web services that makes it possible to change service during execution. A change of service can be interesting for two reasons, the service might be registered but not available or there might be some sort of fault during execution that makes the service unavailable.
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Figueiredo, Rafael Saraiva. "Name service for accessing personal services from Web servers." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/18566.
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Mestrado em Engenharia de Computadores e TelemáticaO propósito desta tese teve como base o desenvolvimento de um mecanismo que permitisse que servidores Web (ou serviços) descobrissem e usassem serviços Web que executam localmente em relação aos clientes Web (serviços pessoais). Para conseguir isto, desenvolvemos uma solução que permita a um servidor de nomes local a descoberta de serviçoos pessoais (i.e., resolver nomes para referências para serviços) e uma solução que permita aos servidores Web a possibilidade de invocar esses serviços pessoas usando as referências obtidas. A comunicação entre os servidores Web e o servidor de nomes local ou os serviços pessoais e mediada pelo cliente Web local (um navegador) usando um novo mecanismo de redireção HTTP.
HTTP, Web service, personal service, Broker, browser, HTTP redirection, name server. The purpose of this thesis was to devise a mechanism to allow Web servers (or services) to nd out and use other Web services running locally to Web clients (personal services). To do so, we had to create a solution for having a local name server to nd out personal services (i.e., resolve names to service handles) and a solution for allowing Web servers to invoke personal services given those handles. The communication between the Web servers and the local name server or the personal services is mediated by the Web client (a browser) using a new HTTP redirection mechanism.
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Bennara, Mahdi. "Linked service integration on the semantic web." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI055.
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L'informatique orientée services facilite l'interopérabilité entre les systèmes distribues. Depuis quelques années, l'émergence du Web sémantique a pose de nouveaux défis pour la communauté de recherche dans les calculs et la compatibilité sémantique des données. L'approche « services » et le Web sémantique constituent une piste prometteuse pour remédier aux problèmes qui entravent les deux domaines. D'une part l'orientation services permet d'assurer l'interopérabilité des données et des traitements au niveau sémantique, et d'autre part le Web sémantique permet d'automatiser les taches de manipulation de services à un haut niveau. Dans le cadre de notre travail de recherche, nous avons détaillé les défis que rencontre la communauté de chercheurs dans l'intégration des pratiques de l'orientation services dans le Web sémantique, et plus particulièrement l'intégration des services REST dans l'implémentation du Web qui repose sur les principes du « Linked Data » pour constituer ce que l'on appelle les « RESTful Linked Services ». Les défis en question sont : La description, la découverte, la sélection et la composition. Nous avons proposé une solution pour chacun de ces défis. Les contributions que nous avons proposées sont : la structure de descripteur, un algorithme de découverte sémantique, un algorithme de sélection base sur Skyline et les répertoires de composition. Nous pensons que l'ensemble de contributions que nous avons proposées peut être adopte par les fournisseurs de services sur le Web afin de faciliter l'intégration des pratiques du sémantique Web avec les technologies des services et de REST en particulier. Ceci permettra donc d'automatiser les taches de manipulation de services a un haut niveau, tel que la découverte sur la base de concepts sémantiques, la sélection sur la base de propriétés non-fonctionnelles et de qualité de services et la composition de plusieurs services hétérogènes, sur le plan des données ainsi que sur le plan des traitements, afin d'obtenir des services composites avec de la valeur ajoutéeService Oriented Computing allows interoperability between distributed systems. In the last years, the emergence of the semantic Web opened new challenges for the research community regarding semantic interoperability on the data and processing levels. The convergence of service orientation and the semantic Web together is a promising effort to solve the problems that hampered both research fields. On the one hand, service orientation allows interoperability on the data and processing levels, and on the other hand, semantic Web allows the automation of high-level service manipulation tasks. In our research, we detail the challenges encountered by the research community to integrate the service orientation practices with the semanticWeb, more precisely, integrating REST-based services with the semantic Web implementation based on Linked Data principles to obtain RESTful Linked Services. The challenges in question are : description, discovery, selection and composition. We proposed a solution for each of these challenges. The contributions we proposed are : The descriptor structure, a semantically-enabled discovery algorithm, a Skyline-based selection algorithm and composition directories. We think that these contributions can be adopted by service providers on the Web in order to allow a seamless integration of semantic Web practices with the service technologies and REST in particular. This allows the automation of high-level service manipulation tasks, such as semantically-enabled discovery, QoS-based selection and the composition of heterogeneous services, be it on the data or processing level, in order to create value-added composite services
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He, Qiang. "Lifetime service level agreement management for service composition." Swinburne Research Bank, 2009. http://hdl.handle.net/1959.3/68739.
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Thesis (Ph.D) - [Faculty of Information and Communication Technologies], Swinburne University of Technology, 2009.Typescript. A thesis submitted to [Faculty of Information and Communication Technologies], Swinburne University of Technology for the degree of Doctor of Philosophy. "March 2009". Bibliography: p. 136-141.
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Benouaret, Karim. "Advanced techniques for Web service query optimization." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10177/document.
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De nos jours, nous assistons à l’émigration du Web de données vers le Web orienté services. L’amélioration des capacités et fonctionnalités des moteurs actuels de recherche sur le Web, par des techniques efficaces de recherche et de sélection de services, devient de plus en plus importante. Dans cette thèse, dans un premier temps, nous proposons un cadre de composition de services Web en tenant compte des préférences utilisateurs. Le modèle fondé sur la théorie des ensembles flous est utilisé pour représenter les préférences. L’approche proposée est basée sur une version étendue du principe d’optimalité de Pareto. Ainsi, la notion des top-k compositions est introduite pour répondre à des requêtes utilisateurs de nature complexe. Afin d’améliorer la qualité de l’ensemble des compositions retournées, un second filtre est appliqué à cet ensemble en utilisant le critère de diversité. Dans un second temps, nous avons considéré le problème de la sélection des services Web en présence de préférences émanant de plusieurs utilisateurs. Une nouvelle variante, appelée Skyline de services à majorité, du Skyline de services traditionnel est défini. Ce qui permet aux utilisateurs de prendre une décision « démocratique » conduisant aux services les plus appropriés. Un autre type de Skyline de services est également discuté dans cette thèse. Il s’agit d’un Skyline de Services de nature graduelle et se fonde sur une relation de dominance floue. Comme résultat, les services Web présentant un meilleur compromis entre les paramètres QoS sont retenus, alors que les services Web ayant un mauvais compromis entre les QoS sont exclus. Finalement, nous avons aussi absorbé le cas où les QoS décrivant les services Web sont entachés d’incertitude. La théorie des possibilités est utilisée comme modèle de l’incertain. Ainsi, un Skyline de Services possibilité est proposé pour permettre à l’utilisateur de sélectionner les services Web désirés en présence de QoS incertains. De riches expérimentations ont été conduites afin d’évaluer et de valider toutes les approches proposées dans cette thèseAs we move from a Web of data to a Web of services, enhancing the capabilities of the current Web search engines with effective and efficient techniques for Web services retrieval and selection becomes an important issue. In this dissertation, we present a framework that identifies the top-k Web service compositions according to the user fuzzy preferences based on a fuzzification of the Pareto dominance relationship. We also provide a method to improve the diversity of the top-k compositions. An efficient algorithm is proposed for each method. We evaluate our approach through a set of thorough experiments. After that, we consider the problem of Web service selection under multiple users preferences. We introduce a novel concept called majority service skyline for this problem based on the majority rule. This allows users to make a “democratic” decision on which Web services are the most appropriate. We develop a suitable algorithm for computing the majority service skyline. We conduct a set of thorough experiments to evaluate the effectiveness of the majority service skyline and the efficiency of our algorithm. We then propose the notion of α-dominant service skyline based on a fuzzification of Pareto dominance relationship, which allows the inclusion of Web services with a good compromise between QoS parameters, and the exclusion ofWeb services with a bad compromise between QoS parameters. We develop an efficient algorithm based on R-Tree index structure for computing efficiently the α-dominant service skyline. We evaluate the effectiveness of the α-dominant service skyline and the efficiency of the algorithm through a set of experiments. Finally, we consider the uncertainty of the QoS delivered by Web services. We model each uncertain QoS attribute using a possibility distribution, and we introduce the notion of pos-dominant service skyline and the notion of nec-dominant service skyline that facilitates users to select their desired Web services with the presence of uncertainty in their QoS. We then developappropriate algorithms to efficiently compute both the pos-dominant service skyline and nec-dominant service skyline. We conduct extensive sets of experiments to evaluate the proposed service skyline extensions and algorithms
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Abdyldaeva, Rahat. "Qos-aware Service Selection For Web Service Composition." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614369/index.pdf.
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Composition of web services is one of the flexible and easiest approaches for
creating composite services that fulfill complex tasks. Together with providing
convenience in creation of new software applications, service composition has
various challenges. One of them is the satisfaction of user-defined Quality of Service
(QoS) requirements while selecting services for a composition. Load balancing issue
is another challenge as uncontrolled workload may lead to violation of service
providers&rsquoQoS declarations. This thesis work proposes a QoS aware method for optimum service composition while taking into account load balancing. M/M/C queuing model is utilized for the individual services to determine sojourn time distribution for possible compositions. Percentile of the execution time, price and availability are considered as QoS parameters. Proposed algorithm selects the optimum composition according to QoS constraints and utility provided by the services. The performance of the method is evaluated by custom simulation software and is compared to two other methods, random selection and average execution timebased optimal service selection.
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Ai, Lifeng. "QoS-aware web service composition using genetic algorithms." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/46666/1/Lifeng_Ai_Thesis.pdf.
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Web service technology is increasingly being used to build various e-Applications, in domains such as e-Business and e-Science. Characteristic benefits of web service technology are its inter-operability, decoupling and just-in-time integration. Using web service technology, an e-Application can be implemented by web service composition — by composing existing individual web services in accordance with the business process of the application. This means the application is provided to customers in the form of a value-added composite web service. An important and challenging issue of web service composition, is how to meet Quality-of-Service (QoS) requirements. This includes customer focused elements such as response time, price, throughput and reliability as well as how to best provide QoS results for the composites. This in turn best fulfils customers’ expectations and achieves their satisfaction. Fulfilling these QoS requirements or addressing the QoS-aware web service composition problem is the focus of this project. From a computational point of view, QoS-aware web service composition can be transformed into diverse optimisation problems. These problems are characterised as complex, large-scale, highly constrained and multi-objective problems. We therefore use genetic algorithms (GAs) to address QoS-based service composition problems. More precisely, this study addresses three important subproblems of QoS-aware web service composition; QoS-based web service selection for a composite web service accommodating constraints on inter-service dependence and conflict, QoS-based resource allocation and scheduling for multiple composite services on hybrid clouds, and performance-driven composite service partitioning for decentralised execution. Based on operations research theory, we model the three problems as a constrained optimisation problem, a resource allocation and scheduling problem, and a graph partitioning problem, respectively. Then, we present novel GAs to address these problems. We also conduct experiments to evaluate the performance of the new GAs. Finally, verification experiments are performed to show the correctness of the GAs. The major outcomes from the first problem are three novel GAs: a penaltybased GA, a min-conflict hill-climbing repairing GA, and a hybrid GA. These GAs adopt different constraint handling strategies to handle constraints on interservice dependence and conflict. This is an important factor that has been largely ignored by existing algorithms that might lead to the generation of infeasible composite services. Experimental results demonstrate the effectiveness of our GAs for handling the QoS-based web service selection problem with constraints on inter-service dependence and conflict, as well as their better scalability than the existing integer programming-based method for large scale web service selection problems. The major outcomes from the second problem has resulted in two GAs; a random-key GA and a cooperative coevolutionary GA (CCGA). Experiments demonstrate the good scalability of the two algorithms. In particular, the CCGA scales well as the number of composite services involved in a problem increases, while no other algorithms demonstrate this ability. The findings from the third problem result in a novel GA for composite service partitioning for decentralised execution. Compared with existing heuristic algorithms, the new GA is more suitable for a large-scale composite web service program partitioning problems. In addition, the GA outperforms existing heuristic algorithms, generating a better deployment topology for a composite web service for decentralised execution. These effective and scalable GAs can be integrated into QoS-based management tools to facilitate the delivery of feasible, reliable and high quality composite web services.
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Milanovic, Nikola. "Contract based web service composition." Doctoral thesis, [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980381371.
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Haller, Markus. "Web service execution for BioOpera." Zürich : ETH, Eidgenössische Technische Hochschule Zürich, Institut für Informations- und Kommunikationssysteme, 2003. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=88.
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Agarwal, Anamika 1981. "Versioning of Web service interfaces." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28630.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.Includes bibliographical references (leaves 88-91).
This thesis investigates the problem of "design for change" in the context of Web Service based information systems. It describes the current status of architecting Web Services, an implementation of the Service Oriented Architecture. It also discusses the availability and support for higher level specifications, such as security, that leverage the baseline standards like SOAP (Simple Object Access Protocol), WSDL (Web Service Description Language), and UDDI (Universal Discovery, Description and Integration). This thesis examines versioning as an additional specification. It discusses the Web Service enabled programming environment by addressing the various causes of change. Two levels of versioning are identified to deal with this problem--Schema level and Interface level versioning. For Schema level versioning, the extensibility models and their versioning support are discussed. Other techniques of using distinct namespaces and custom versioning tags are presented by means of samples. The second level of versioning, the Interface Level Versioning, discusses implementation of versioning logic using the current standards of WSDL 1.1. In addition, the ongoing recommendations and efforts in this field are stated.
by Anamika Agarwal.
S.M.
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Contreas, Ricardo. "Context aware Web-service monitoring." Thesis, City University London, 2013. http://openaccess.city.ac.uk/2723/.
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Monitoring the correct behaviour of a service-based system is a necessity and a key challenge in Service Oriented Computing. Several efforts have been directed towards the development of approaches dealing with the monitoring activity of service-based systems. However, these approaches are in general not suitable when dealing with modifications in service-based systems. Furthermore, existing monitoring approaches do not take into consideration the context of the users and how this context may affect the monitor activity. Consequently, a holistic monitor approach, capable of dealing with the dynamic nature of service-based systems and of taking into consideration the user context, would be highly desirable. In this thesis we present a monitor adaptation framework capable of dealing with changes in a service-based system and different types of users interacting with it. More specifically, the framework obtains a set of monitor rules, necessary to verify the correct behaviour of a service-based system, for a particular user. Moreover, the monitor rules verifying the behaviour of a service-based system relate to properties of the context types defined for a user. The main contributions of our work include the general characterisation of a user interacting with a service-based system and the generation of suitable monitor rules.The proposed framework can be applied to any service composition without the need of further modifications. Our work complements previous research carried on in the area of web service monitoring. More specifically, our work generates a set of suitable monitor rules - related to the user context - which are deployed in a run-time monitor component. Our framework has been tested and validated in several cases considering different scenarios.
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Sabah, Mohammad. "Random Variate Generation Web Service." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/35001.
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Simulation and statistical applications often mimic the behavior of a random phenomenon by way of generating random observations that form a known or empirical probability distribution with estimated parameter values. Generation of such random observations is called Random Variate Generation (RVG). The number of simulation and statistical applications provided on the World Wide Web (Web) is on the rise. To facilitate the development of simulation and statistical applications on the Web by way of reuse, there is a need for providing RVG as a Web service. This research involves the development of such a Web service for RVG, which can be invoked programmatically over the Web by using SOAP over the HyperText Transfer Protocol (HTTP) running on top of the Internet. To provide the RVG Web service, an RVG Web application is developed based on the Java 2 Enterprise Edition (J2EE) architecture. The RVG Web application is engineered by using the IBM WebSphere Studio Application Developer and runs on the IBM WebSphere Application Server. A client simulation and statistical application may call the RVG Web service and request the generation of random variates from 27 probability distributions. In addition, the RVG Web service also provides general statistics, scatter plot, and histogram of the requested random variates. The plots and histograms are created in Scalable Vector Graphics (SVG). The RVG Web service: (a) accepts requests in the Extensible Markup Language (XML) format, which is specified according to a request schema, and (b) sends the results to the client application also in the XML format specified according to a reply schema. The interface specification and access information needed to invoke the RVG Web service are provided in the Web Service Description Language (WSDL) document. Any Web-based simulation or statistical application that needs generation of random variates, their scatter plots and histograms, can invoke the RVG Web service programmatically at http://sunfish.cs.vt.edu/RVGWebService .Master of Science
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PANZIERA, LUCA. "Service matchmaking: exploiting the Web." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/46143.
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Services are software components with standard interfaces that enable rapid and flexible development of distributed systems over the Web. The literature proved that service matchmaking is the most effective approach for finding services that fulfil user needs. Available matchmaking tools require a repository composed of semi-structured descriptions that specify service properties according to a shared model.
The diffusion of services that provide public functionalities on the Web, called Web APIs, is leading to a new scenario in which increasing Web information about services is available on dispersed sources, such as official documentations, wikis, forums, blogs and social networks.
In order to exploit Web information to support service matchmaking, several issues must be addressed. Web sources provides service information according to heterogeneous data formats, models and vocabularies. Web information is dynamic, then can change over time. Available descriptions can be invalid in terms of accuracy, currency and trustworthiness. Sources provide partial or contradictory information about same services. Finally, some relevant properties, such as service provider popularity or quality of service documentation, are not explicitly reported on the Web, then may be wrongly interpreted by users through personal subjective evaluations.
This thesis provides an overall approach for enabling effective and efficient service match- making on Web information by addressing the issues above. The approach constructs semantic descriptions by extracting (i) explicit property values from heterogeneous non- semantic sources; (ii) subjective property values through social media. Then, quality assessments on Web information are exploited for fusing valid descriptions extracted by several sources and performing effective matchmaking. The overall approach is implemented through a lightweight distributed architecture which focuses on scalability issues by managing big amount of Web information about services.
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Alwagait, Esam Abdullah K. "A Broker based Web Service Allocation Mechanism." Doctoral thesis, Universitat Politècnica de València, 2011. http://hdl.handle.net/10251/12500.
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Los servicios web son considerados por la industria y la investigación de facto por proporcionar funcionalidad de forma distribuida que sea usable en entornos heterogéneos. En pocas palabras, los servicios web son funcionalidad empaquetada que se basa en un conjunto de estándares que facilitan la definición de los métodos de los servicios web, sus números y formatos de entrada, así como sus números y formatos de salida. En combinación con la replicación, los servicios web pueden proporcionar soluciones de optimización del rendimiento a un número ilimitado de aplicaciones de negocio de la vida real. Sin embargo, cuando se habla de replicación es necesario plantearse cómo asignar o elegir las réplicas para proporcionar el mejor rendimiento posible. Esta tesis está dedicada a responder a esta pregunta.
La tesis se titula "Un mecanismo de asignación de servicios web basado en Broker" donde un paradigma de ejecución (Proteus) es presentado, y varios algoritmos de asignación son también presentados, examinados y analizados para mostrar el óptimo. La tesis se centra en el componente broker del paradigma de ejecución. Este componente tiene embebido el algoritmo de asignación. Por otra parte, la tesis se centra en el Algoritmo de menor tiempo de servicio (LRT), el cual funciona asignando las réplicas del servicio web que proporcionan un tiempo de respuesta más rápido.
La tesis ofrece todo el trabajo de fondo necesario, así como toda la investigación relacionada. Contiene una parte simulada, así como una descripción de un sistema de la vida real (Proteus). Contiene también una sección dedicada a analizar los resultados de los registros de ejecución y analizar las diferentes variaciones de los entornos (homogéneos y heterogéneos), el número de replicas y el nivel de paralelismo. Los registros son examinados y las conclusiones expuestas.Alwagait, EAK. (2011). A Broker based Web Service Allocation Mechanism [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/12500
Palancia
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Ziembicki, Joanna. "Distributed Search in Semantic Web Service Discovery." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/1103.
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This thesis presents a framework for semantic Web Service discovery using descriptive (non-functional) service characteristics in a large-scale, multi-domain setting. The framework uses Web Ontology Language for Services (OWL-S) to design a template for describing non-functional service parameters in a way that facilitates service discovery, and presents a layered scheme for organizing ontologies used in service description. This service description scheme serves as a core for desigining the four main functions of a service directory: a template-based user interface, semantic query expansion algorithms, a two-level indexing scheme that combines Bloom filters with a Distributed Hash Table, and a distributed approach for storing service description. The service directory is, in turn, implemented as an extension of the Open Service Discovery Architecture. The search algorithms presented in this thesis are designed to maximize precision and completeness of service discovery, while the distributed design of the directory allows individual administrative domains to retain a high degree of independence and maintain access control to information about their services.
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Wei, Yanfang. "Control synchronous web-based training using web services." ScholarWorks@UNO, 2004. http://louisdl.louislibraries.org/u?/NOD,145.
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Thesis (M.S.)--University of New Orleans, 2004.Title from electronic submission form. "A thesis ... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Computer Science."--Thesis t.p. Vita. Includes bibliographical references.
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Gomadam, Karthik Rajagopal. "Semantics Enriched Service Environments." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1251246445.
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Kuzu, Mehmet. "Automatic Web Service Composition With Ai Planning." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610756/index.pdf.
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In this thesis, some novel ideas are presented for solving automated web service composition problem. Some possible real world problems such as partial observability of environment, nondeterministic effects of web services, service execution failures are solved through some mechanisms. In addition to automated web service composition, automated web service invocation task is handled in this thesis by using reflection mechanism. The proposed approach is based on AI planning. Web service composition problem is translated to AI planning problem and a novel AI planner namely &ldquoSimplanner&rdquo
that is designed for working in highly dynamic environments under time constraints is adapted to the proposed system. World altering service calls are done by conforming to the WS-Coordination and WS-Business Activity web service transaction specifications in order to physically repair failure situations and prevent undesired side effects of aborted web service composition efforts.
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Hwang, Yousub. "Facilitating Web Service Discovery and Publishing: A Theoretical Framework, A Prototype System, and Evaluation." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/196129.
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The World Wide Web is transitioning from being a mere collection of documents that contain useful information toward providing a collection of services that perform useful tasks. The emerging Web service technology has been envisioned as the next technological wave and is expected to play an important role in this recent transformation of the Web. By providing interoperable interface standards for application-to-application communication, Web services can be combined with component-based software development to promote application interaction and integration within and across enterprises. To make Web services for service-oriented computing operational, it is important that Web services repositories not only be well-structured but also provide efficient tools for an environment supporting reusable software components for both service providers and consumers. As the potential of Web services for service-oriented computing is becoming widely recognized, the demand for an integrated framework that facilitates service discovery and publishing is concomitantly growing.In our research, we propose a framework that facilitates Web service discovery and publishing by combining clustering techniques and leveraging the semantics of the XML-based service specification in WSDL files. We believe that this is one of the first attempts at applying unsupervised artificial neural network-based machine-learning techniques in the Web service domain. Our proposed approach has several appealing features: (1) It minimizes the requirements of prior knowledge from both service providers and consumers, (2) It avoids exploiting domain-dependent ontologies,(3) It is able to visualize the information space of Web services by providing a category map that depicts the semantic relationships among them,(4) It is able to semi-automatically generate Web service taxonomies that reflect both capability and geographic context, and(5) It allows service consumers to combine multiple search strategies in a flexible manner.We have developed a Web service discovery tool based on the proposed approach using an unsupervised artificial neural network and empirically evaluated the proposed approach and tool using real Web service descriptions drawn from operational Web services repositories. We believe that both service providers and consumers in a service-oriented computing environment can benefit from our Web service discovery approach.
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Чеботарьова, Д. В., and В. О. Безлуцький. "Використання технології Amazon WEB Services для обслуговування сервісів." Thesis, ФОП Петров В. В, 2020. https://openarchive.nure.ua/handle/document/16406.
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У збірнику подано тези доповідей восьмої міжнародної науково-технічної конференції “Проблеми інформатизації”. Розглянуті питання за такими напрямами: інформатизація навчального процесу; безпека функціонування, застосування та експлуатація телекомунікаційних систем та мереж; комп’ютерні методи і засоби інформаційних технологій та управління; методи швидкої та достовірної обробки даних в комп’ютерних системах та мережах; сучасні інформаційновимірювальні системи; цивільна безпека (інформаційна підтримка).
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Naim, Hafida. "Réseaux de service web : construction, analyse et applications." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0083.
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Cette thèse se place dans le cadre de services web en dépassant leur description pour considérer leur structuration en réseaux (réseaux d'interaction et réseaux de similitude). Nous proposons des méthodes basées sur les motifs, la modélisation probabiliste et l'analyse des concepts formels, pour améliorer la qualité des services découverts. Trois contributions sont alors proposées: découverte de services diversifiés, recommandation de services et cohérence des communautés de services détectées. Nous structurons d'abord les services sous forme de réseaux. Afin de diversifier les résultats de la découverte, nous proposons une méthode probabiliste qui se base à la fois sur la pertinence, la diversité et la densité des services. Dans le cas de requêtes complexes, nous exploitons le réseau d'interaction de services construit et la notion de diversité dans les graphes pour identifier les services web qui sont susceptibles d'être composables. Nous proposons également un système de recommandation hybride basé sur le contenu et le filtrage collaboratif. L'originalité de la méthode proposée vient de la combinaison des modèles thématiques et les motifs fréquents pour capturer la sémantique commune maximale d'un ensemble de services. Enfin, au lieu de ne traiter que des services individuels, nous considérons aussi un ensemble de services regroupés sous forme de communautés de services pour la recommandation. Nous proposons dans ce contexte, une méthode qui combine la sémantique et la topologie dans les réseaux afin d'évaluer la qualité et la cohérence sémantique des communautés détectées, et classer également les algorithmes de détection de communautésAs a part of this thesis, we exceed the description of web services to consider their structure as networks (i.e. similarity and interaction web service networks). We propose methods based on patterns, topic models and formal concept analysis, to improve the quality of discovered services. Three contributions are then proposed: (1) diversified services discovery, (2) services recommendation and (3) consistency of detected communities. Firstly, we propose modeling the space of web services through networks. To discover the diversified services corresponding to a given query, we propose a probabilistic method to diversify the discovery results based on relevancy, diversity and service density. In case of complex requests, it is necessary to combine multiple web services to fulfill this kind of requests. In this regard, we use the interaction web service network and the diversity notion in graphs to identify all possible services compositions. We also propose a new hybrid recommendation system based on both content and collaborative filtering. Its originality comes from the combination of probabilistic topic models and pattern mining to capture the maximal common semantic of a set of services. Finally, instead of processing individual services, we consider a set of services grouped into service communities for the recommendation. We propose in this context, a new method combining both topology and semantics to evaluate the quality and the semantic consistency of detected communities, and also rank the detection communities algorithms
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Deng, Hui. "Web Service Enabled Mobile Agent System." Thesis, University of Hawaii at Manoa, 2002. http://hdl.handle.net/10125/6942.
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Web Services and Mobile Agents are two most prominent technologies in current distributed computing world. Built on top of existing Web protocols and based on open XML standards, Web Services are emerging to provide a systematic and extensible framework for application-to-application interaction. It is platform and language independent. Web Services are technologies that define the standardized mechanisms to describe, locate, and communicate services on Internet. Mobile agent is considered an essential technology in the development of distributed software application because of its capability to move across distributed environments, interact with local resources and other mobile agents. Mobile agent allows for more flexible and dynamic structure than traditional systems based on the client-server paradigm. This thesis discusses the necessity and benefit of incorporating the location and platform agnostic Web Services into mobile agent system. How Web Services technologies could be used to help to standardize the mobile agent system. A framework of Web Service Enabled Mobile Agent System has been presented and discussed along with the detail of the implementation. Evaluation and verification have been conducted to ensure that the experimented system performs as the way it is expected.ix, 90 leaves
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Ngu, Phuc Huy. "Web applications - New mobile service paradigm." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-19040.
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The explosion of mobile applications both in number and variety raises the need of shedding light on their architecture, composition and quality. Indeed, it is crucial to understand which mobile application paradigm fits better to what type of application and usage. Such understanding has direct consequences on the user experience, the development cost and sale revenues of mobile apps. In this thesis, we identify four main mobile application paradigms and evaluate them from the viewpoints of developers, users and service providers. To ensure objectivity and accuracy we start by defining high level criteria and then breaking down into finer-grained criteria. After a theoretical evaluation an implementation was carried out as a practical verification to ensure that the method adopted in analysis and evaluation is trusted and applicable. The selected application is object recognition app, which is both exciting and challenging to develop.
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Zhang, Shuai. "Benchmarking Performance of Web Service Operations." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-156425.
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Web services are often used for retrieving data from servers providing information of different kinds. A data providing web service operation returns collections of objects for a given set of arguments without any side effects. In this project a web service benchmark (WSBENCH) is developed to simulate the performance of web service calls. Web service operations are specified as SQL statements. The function generator of WSBENCH converts user specified SQL queries into functions and automatically generates a web service. WSBENCH can automatically both generate and deploy web the service operations for exported functions. Furthermore WSBENCH supports controlled experiments, since users can control the characteristics of web service operations such as scalability of data and delay time. The database used in this project is generated by the Berlin Benchmark database generator. A WSBENCH demo is built to demonstrate the functionality. The demo is implemented as a JavaScript program acting as a SOAP client, directly calls WSBENCH services from a web browser. Users can make a web service request by simply providing the web service operation’s name and parameter values list as the input. It makes the WSBENCH very simple to the use.
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Lundmark, Anton. "Web Map Service implementation i .NET." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72364.
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I dagens samhälle så används internet mer och mer för att få fram information, så är även fallet förkartor. I denna uppsats, som gjorts på uppdrag av Tieto Sweden Healthcare & Welfare för att kunnaanvändas i systemet Laps Care, kommer det tas upp lösningar för att hämta geografisk data viakarttjänster med hjälp av Web Map Service (WMS) tjänster i en .NET applikation.Detta examensarbete kommer att ta upp, på en grundläggande nivå, hur WMS-standarden kananvändas av en klient för att visa digitala kartor från en WMS-tjänst samt lite kort om andraalternativ till WMS så som Web Map Service Tile Cache (WMS-C) och Tile Map Service (TMS)tjänster. Det ges olika förslag på open source komponenter som kan användas för att hantera sådanatjänster med fokus på SharpMap som valdes att användas i prototypen som gjordes för att visa huren sådan klient kan se ut.Uppsatsen kommer också behandla kartografi där det kortfattat förklaras om vilka riktlinjer somborde tas för en karta.I andra stycket tas kortfattat upp hur webbtjänster fungerar och även vad det finns för för- ochnackdelar att använda sig av sådana tjänster.Det kommer också förklaras vad Geografiska informationssystem (GIS) är och hur det användsidag.Sammanfattningsvis så utvecklades en fungerande prototyp med hjälp av open source komponentenSharpMap som kan visa kartor från WMS, WMS-C och TMS tjänster och om en ERSI Shapefilmed vägdata finns tillgänglig så går det att söka efter gator.
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Oh, Sangyoon. "Web service architecture for mobile computing." [Bloomington, Ind.] : Indiana University, 2006. 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:3229598.
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Thesis (Ph.D.)--Indiana University, Dept. of Computer Science, 2006."Title from dissertation home page (viewed July 11, 2007)." Source: Dissertation Abstracts International, Volume: 67-08, Section: B, page: 4529. Adviser: Geoffrey C. Fox.
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Reichel, Christian. "OpenXL : an adaptable Web Service middleware." kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:29756.
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Liang, Lin. "Adopting Pragmatics in Web Service Discovery." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520115.
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Andrade, Leandro José Silva. "SWoDS: Semantic Web (of Data) Service." Instituto de Matemática. Departamento de Ciência da Computação, 2014. http://repositorio.ufba.br/ri/handle/ri/19286.
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Criada com a proposta inicial de conectar basicamente documentos HTML, a Web hoje expandiu suas capacidades, tornando-se um ambiente bastante heterogêneo de aplicações, recursos, dados e usuários que interagem entre si. A proposta da Web Semântica, associada aos Serviços Web, busca estabelecer padrões que viabilizem a comunicação entre aplicações heterogêneas na Web. A Web de Dados, outra linha de evolução da Web, fornece orientações (Linked Data) sobre como usar as tecnologias da Web Semântica para publicar e definir ligações semânticas entre dados de diferentes fontes. Contudo, existe uma lacuna na integração entre aplicações baseadas em Serviços Web e aplicações da Web de Dados. Essa lacuna ocorre porque os Serviços Web são “executados”, enquanto que a Web de Dados é “consultada”. Dessa forma, esta dissertação apresenta o Semantic Web (of Data) Services (SWoDS) com objetivo de prover Serviços Web a partir de bases Linked Data. O Semantic Web (of Data) Services pode preencher a lacuna entre Serviços Web e aplicações baseadas na Web de Dados, fazendo que a Web de Dados seja “executada” através de Serviços Web Semânticos. Assim, permitindo que dados Linked Data, através do SWoDS, integrem aos Serviços Web, por meio de operações de composição automática e descoberta de serviços.
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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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Ren, Wei. "Dynamic Self-healing for Composite Services using Semantic Web Service Technology." Thesis, Griffith University, 2009. http://hdl.handle.net/10072/366899.
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Service-Oriented Architecture (SOA) has emerged as a promising paradigm for building loosely coupled, standard-based and Web-enabled distributed applications and systems. The essential notion and technology of SOA is Web service which is the high level of abstraction of functionality with well-defined interfaces. If a Web service is further equipped with well-defined semantics, it is termed Semantic Web service. With the power of Semantics of Web services, SOA has created many new opportunities to meet the challenge of enterprise integration and provides great potentials for automated integration. However, this promising paradigm has also imposed a great challenge to the service discovery, invocation, composition, self-healing capability and so on. Among all those issues, service composition, which is defined as aggregation of other services to provide a more sophisticated, value-added service, is at the core of many applications of Web services. From a service oriented perspective, application integration which is a long standing issue in industry can be achieved via service composition. Nevertheless, the dynamics in real application context when addressing the service composition very much complicate the matter, and it is often desirable to accomplish composition with high degree of serviceability, especially when environment changes or when services previously used becomes unavailable. One of approaches to serviceability is the capability of self-healing with less or no external interventions when changes occur. Service composition and self healing of composite services are the major concerns of the research work described in this thesis. The main objectives are to extensively explore semantics for facilitating Web service composition and for realizing dynamic self-healing for composite services in a semantic-enhanced service-oriented manufacturing Collaborative Virtual Enterprise (CVE).
A CVE is a temporary alliance of enterprises to share skills or core competencies and resources in order to better respond to business opportunities in a more collaborative rather than competitive manner. Dynamism is a salient feature of CVE. A CVE needs to be dynamically formulated, its business processes need to be dynamically configured and executed to respond to the dynamic market. A CVE needs to quickly integrate its systems, applications, and services to fulfill its business goals. Taking semantic Web service-oriented approach, we shall first establish a semantic rich service-oriented manufacturing CVE where a collection of Semantic Web services are developed.
Within the service-oriented paradigm, two different approaches – BPEL and OWL-S are investigated to realize service composition in a service-oriented manufacturing CVE. The critical analysis of BPEL and OWL-S is conducted in the manufacturing CVE scenario. Five key criteria for evaluating technologies of service composition are identified. Moreover, semantic-driven services composer based on OWL-S is developed and the goal-oriented forward-chaining algorithm is presented.
In order to systematically address semantic web service composition, a business rule enhanced semantic service composition framework is further presented and analyzed. We adopt the divide-and-conquer strategy and propose a hierarchical composition architecture to handle tasks of complex service composition. In this framework, the description of each Web Service is enhanced with rule-based modeling of the essential business logic behind the service interface. A formal notion of service utilities has been provided. Complete processes for calculating the service utilities have also been introduced through processing and evaluating these business rules. A PC manufacturing CVE derived from a practical industrial setting is designed and a prototype system is developed to experimentally evaluate the effectiveness of our service composition framework.
In a practical industrial setting, the effective and efficient service composition is often not sufficient for dynamic natures of CVE. Once formulated, a composite service for a business goal must be able to address many dynamic changing issues, and in this case self-healing capability of a composite service has appeared as an attractive approach. Self-healing refers to a capability of a service to maintain its serviceability by healing itself when its component service becomes unavailable or downgraded. In this research, a self-healing capable composite service execution system is proposed. The execution system takes advantage of the complementary strengths of OWL-S and BPEL in the following ways: (1) a dynamic self-healing mechanism is proposed which can dynamically identify suitable alternatives and replace faulty services such that a composite service can be performed successfully despite of unexpected exceptions; (2) an OWL-S process to BPEL process Mapper is presented which can translate OWL-S process to BPEL process and meanwhile embed the self-healing mechanism into BPEL workflow. Semantic Web service technology plays its part for service matching and selection during the self-healing process in a sense that Semantic Web services are equipped with rich business rules in a domain-dependent manner. A concrete scenario – PC manufacturing CVE is used to demonstrate the effectiveness of self-healing capable composite service execution system.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Information and Communication Technology
Science, Environment, Engineering and Technology
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Oh, Se Hun. "High-Level Test-Driven Learning Using Web Application and Web Service." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1124.
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In order to introduce learning cases with real-world contexts to the Computer Science students in their early stage of learning, a set of Web applications that utilize Web services are simplified and customized to demonstrate the core concept of high-level test-driven learning methodology. Four e-commerce Web applications were implemented for this project. These applications show how real-world Web services work and interact with each other. By systematically planting a number of errors into the services, we created a learning environment for the students to understand the system structure and basic programming through their critical thinking. A goal is to keep students' interest in computer science. In doing so, a set of features that help students observe the systems' behavior are designed, and collectively formed a pattern of user interface "the Learner's Corner."
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Al-Canaan, Amer. "Analyse et amélioration de la qualité de services WEB multimédia et leurs mises en oeuvre sur ordinateur et sur FPGA." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5973.
Full textAbstract:
Résumé : Les services Web, issus de l’avancée technologique dans le domaine des réseaux informatiques et des dispositifs de télécommunications portables et fixes, occupent une place primordiale dans la vie quotidienne des gens. La demande croissante sur des services Web multimédia (SWM), en particulier, augmente la charge sur les réseaux d’Internet, les fournisseurs de services et les serveurs Web. Cette charge est essentiellement due au fait que les SWM de haute qualité nécessitent des débits de transfert et des tailles de paquets importants. La qualité de service (par définition, telle que vue par l’utilisateur) est influencée par plusieurs facteurs de performance, comme le temps de traitement, le délai de propagation, le temps de réponse, la résolution d’images et l’efficacité de compression.
Le travail décrit dans cette thèse est motivé par la demande continuellement croissante de nouveaux SWM et le besoin de maintenir et d’améliorer la qualité de ces services. Nous nous intéressons tout d’abord à la qualité de services (QdS) des SWM lorsqu’ils sont mis en œuvre sur des ordinateurs, tels que les ordinateurs de bureau ou les portables. Nous commençons par étudier les aspects de compatibilité afin d’obtenir des SWM fonctionnant de manière satisfaisante sur différentes plate-formes. Nous étudions ensuite la QdS des SWM lorsqu’ils sont mis en œuvre selon deux approches différentes, soit le protocole SOAP et le style RESTful. Nous étudions plus particulièrement le taux de compression qui est un des facteurs influençant la QdS.
Après avoir considéré sous différents angles les SWM avec mise en œuvre sur des ordinateurs, nous nous intéressons à la QdS des SWM lorsqu’ils sont mis en œuvre sur FPGA. Nous effectuons alors une étude et une mise en œuvre qui permet d’identifier les avantages à mettre en œuvre des SWM sur FPGA.
Les contributions se définissent en cinq volets comme suit :
1. Nous introduisons des méthodes de création, c’est-à-dire conception et mise en œuvre, de SWM sur des plate-formes logicielles hétérogènes dans différents environnements tels que Windows, OS X et Solaris. Un objectif que nous visons est de proposer une approche permettant d’ajouter de nouveaux SWM tout en garantissant la compatibilité entre les plate-formes, dans le sens où nous identifions les options nous permettant d’offrir un ensemble riche et varié de SWM pouvant fonctionner sur les différentes plate-formes.
2. Nous identifions une liste de paramètres pertinents influençant la QdS des SWM mis en œuvre selon le protocole SOAP et selon le style REST.
3. Nous développons un environnement d’analyse pour quantifier les impacts de chaque paramètre identifié sur la QdS de SWM. Pour cela, nous considérons les SWM mis en œuvre selon le protocole SOAP et aussi selon style REST. Les QdS obtenues avec SOAP et REST sont comparées objectivement. Pour faciliter la comparaison, la même gamme d’images (dans l’analyse de SWM SOAP) a été réutilisée et les mêmes plate-formes logicielles.
4. Nous développons une procédure d’analyse qui permet de déterminer une corrélation entre la dimension d’une image et le taux de compression adéquat. Les résultats obtenus confirment cette contribution propre à cette thèse qui confirme que le taux de compression peut être optimisé lorsque les dimensions de l’image ont la propriété suivante : le rapport entre la longueur et la largeur est égal au nombre d’or connu dans la nature. Trois libraires ont été utilisées à savoir JPEG, JPEG2000 et DjVu.
5. Dans un volet complémentaire aux quatre volets précédents, qui concernent les SWM sur ordinateurs, nous étudions ainsi la conception et la mise en œuvre de SWM sur FPGA. Nous justifions l’option de FPGA en identifiant ses avantages par rapport à deux autres options : ordinateurs et ASICs. Afin de confirmer plusieurs avantages identifiés, un SWM de QdS élevée et de haute performance est créé sur FPGA, en utilisant des outils de conception gratuits, du code ouvert (open-source) et une méthode fondée uniquement sur HDL. Notre approche facilitera l’ajout d’autres modules de gestions et d’orchestration de SWM.
6. La mise à jour et l’adaptation du code open-source et de la documentation du module Ethernet IP Core pour la communication entre le FPGA et le port Ethernet sur la carte Nexys3. Ceci a pour effet de faciliter la mise en œuvre de SWM sur la carte Nexys3. // Abstract : Web services, which are the outcome of the technological advancements in IT networks
and hand-held mobile devices for telecommunications, occupy an important role in our
daily life. The increasing demand on multimedia Web services (MWS), in particular,
augments the load on the Internet, on service providers and Web servers. This load
is mainly due to the fact that the high-quality multimedia Web services necessitate
high data transfer rates and considerable payload sizes. The quality of service (QoS,
by definition as it is perceived by the user) is influenced by several factors, such as
processing time, propagation delay, response time, image resolution and compression
efficacy.
The research work in this thesis is motivated by the persistent demand on new MWS,
and the need to maintain and improve the QoS. Firstly, we focus on the QoS of MWS
when they are implemented on desktop and laptop computers. We start with studying
the compatibility aspects in order to obtain MWS functioning satisfactorily on different
platforms. Secondly, we study the QoS for MWS implemented according to the SOAP
protocol and the RESTful style. In particular, we study the compression rate, which is
one of the pertinent factors influencing the QoS.
Thirdly, after the study of MWS when implemented on computers, we proceed with the
study of QoS of MWS when implemented on hardware, in particular on FPGAs. We
achieved thus comprehensive study and implementations that show and compare the
advantages of MWS on FPGAs.
The contributions of this thesis can be resumed as follows:
1. We introduce methods of design and implementation of MWS on heterogeneous
platforms, such as Windows, OS X and Solaris. One of our objectives is to
propose an approach that facilitates the integration of new MWS while assuring
the compatibility amongst involved platforms. This means that we identify the
options that enable offering a set of rich and various MWS that can run on different
platforms.
2. We determine a list of relevant parameters that influence the QoS of MWS.
3. We build an analysis environment that quantifies the impact of each parameter on
the QoS of MWS implemented on both SOAP protocol and RESTful style. Both
QoS for SOAP and REST are objectively compared. The analysis has been held on
a large scale of different images, which produces a realistic point of view describing
the behaviour of real MWS.
4. We develop an analysis procedure to determine the correlation between the
aspect ratio of an image and its compression ratio. Our results confirm that
the compression ratio can be improved and optimised when the aspect ratio of
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an image is close to the golden ratio, which exists in nature. Three libraries of
compression schemes have been used, namely: JPEG, JPEG2000 and DjVu.
5. Complementary to the four contributions mentioned above, which concern the
MWS on computers, we study also the design and implementation of MWS on
FPGA. This is justified by the numerous advantages that are offered by FPGAs,
compared to the other technologies such as computers and ASICs. In order to
highlight the advantages of implementing MWS on FPGA, we developed on FPGA
a MWS of high performance and high level of QoS. To achieve our goal, we utilised
freely available design utilities, open-source code and a method based only on
HDL. This approach is adequate for future extensions and add-on modules for
MWS orchestration.
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Slaimi, Fatma. "Découverte et recommandation de services Web." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0069.
Full textAbstract:
Le Web est devenu une plateforme universelle d’hébergement d'applications hétérogènes. Dans ce contexte, les services Web se sont imposés comme une technologie clé pour permettre l’interaction entre diverses applications. Les technologies standards proposées autour des services Web permettent la programmation, plutôt manuelle, de ces applications. Pour favoriser une programmation automatique à base de services web, un problème majeur se pose : celui de leur découverte. Plusieurs approches adressant ce problème ont été proposées dans la littérature. L’objectif de cette thèse est d’améliorer le processus de découverte de services en exploitant trois pistes de recherche. La première consiste à proposer une approche de découverte qui combine plusieurs techniques de matching. La deuxième se base sur une validation des services retournés par un processus de découverte automatique en se basant sur les compétences utilisateurs. Ces approches ne prennent pas en considération l’évolution de services dans le temps et les préférences des utilisateurs. Pour remédier à ces lacunes plusieurs approches incorporent des techniques de recommandation. La majorité d'entre eux sont basées sur les évaluations des propriétés de QdS. Pratiquement, ces évaluations sont rarement disponibles. D’autres systèmes exploitent les relations de confiance. Ces relations sont établies en se basant sur les évaluations de services. Or, invoquant le même service ne signifie pas obligatoirement avoir les mêmes préférences. D’où, nous proposons, l’exploitation des relations d’intérêts entre les utilisateurs pour recommander des services. L’approche s’appuie sur une modélisation orientée base de données graphesThe Web has become an universal platform for content hosting and distributed heterogeneous applications that can be accessed manually or automatically. In this context, Web services have established themselves as a key technology for deploying interactions across applications. The standard Web services technologies allow and facilitate the manual programming of these applications. To promote automatic programming based on Web services, a major problem arises : that of their discovery. Several approaches addressing this problem have been proposed in the literature. The aim of this thesis is to improve the Web services discovery process. We proposed three approaches. We proposed a Web services discovery approach that combines several matching techniques. The second consists on the validation of the services returned by an automatic process of discovery using users’ competencies. These approaches do not take into account the evolution of services over time and user preferences. To address these shortcomings, several approaches incorporate referral techniques to assist the discovery process. A large majority of these approaches are based on assessments of QoS properties. In practice, these assessments are rarely available. In other systems, trust relationships between users and services are used. These relationships are established based on invocations evaluations of similar services. However, invoking the same service do not necessarily mean having the same preferences. Hence, we propose, in our third approach, the use of the relations of interest between users to recommend services. The approach relies on modeling services’ ecosystem by database graphs
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COMERIO, MARCO. "Web service contracts: specification, selection and composition." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/7779.
Full textAbstract:
Web services promise universal interoperability and integration of
services developed by independent providers to execute business processes by discovering and composing services distributed over
the Internet. This means that a key factor to build complex and valuable processes among cooperating organizations relies on the
efficiency of discovering appropriate Web services and composing them. The increasing availability of Web services that offer
similar functionalities requires mechanisms to go beyond the pure functional discovery and composition of Web services.
A promising solution towards the automatic enactment of valuable processes consists in enhancing Web service discovery and composition with the evaluation of semantic contracts that define non-functional properties (NFPs) and applicability conditions associated with a Web service. Nevertheless, currently there is a lack of tools and algorithms that fully support this solution due to several open issues. First, existing languages do not show the expressivity necessary for Web service contract specifications. Second, there is a lack of standard languages that determines
heterogeneity in Web service contract specifications raising interoperability issues. Third, pure semantic approaches to
enhance Web service discovery allows for detailed descriptions but present performance problems due to current limitations of semantic tools when dealing with reasoning tasks. Fourth, Web service contract compatibility evaluation is not supported by existing composition tools when combining different services from different providers.
This dissertation addresses these open issues and proposes solutions in terms of models, algorithms and tools.
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Ben, hadj yahia Elyas. "A Language-Based Approach for Web Service Composition." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0783/document.
Full textAbstract:
Au vu des dernières avancées dans le domaine de l’ingénierie web, ainsi qu’avec la baisse de coût du cloud computing, les architectures orientées services sont rapidement devenues la solution prépondérante pour fournir des services à valeur ajoutée aux clients. Suite à cette tendance, la composition de services tiers est devenue un paradigme de référence pour le développement d’applications robustes et riches, ou encore pour l’automatisation de processus métiers. Avec la disponibilité de centaines de milliers de services et APIs web, la réalisation de telles intégrations devient lourde et fastidieuse quand effectuée manuellement. Par ailleurs, chaque client peut exiger des besoins et politiques d’intégration différentes, ce qui complexifie davantage la tâche. De plus, fournir une telle solution qui soit à la fois robuste et scalable est une tâche non-triviale. Il est donc primordial d’étudier comment coordonner de manière efficace les interactions entre les services web existants. Ainsi, cette thèse vise à étudier les problématiques liées à la composition de services web dans le contexte des pratiques de développement web modernes. Nous présentons un cadre architectural permettant la spécification de compositions de services web grâce à une approche orientée langage, et montrons comment supporter leur exécution de manière scalable grâce à MEDLEY, une plateforme légère et orientée événementsIn light of the recent advances in the field of web engineering, along with the decrease of cost of cloud computing, service-oriented architectures rapidly became the leading solution in providing valuable services to clients. Following this trend, the composition of third-party services has become a successful paradigm for the development of robust and rich distributed applications, as well as automating business processes. With the availability of hundreds of thousands of web services and APIs, such integrations become cumbersome and tedious when performed manually. Furthermore, different clients may require different integration requirements and policies, which further complexifies the task. Moreover, providing such a solution that is both robust and scalable is a non-trivial task. Therefore, it becomes crucial to investigate how to efficiently coordinate the interactions between existing web services. As such, this thesis aims at investigating the underlying challenges in web service composition in the context of modern web development practices. We present an architectural framework to support the specification of web service compositions using a language-based approach, and show how we support their execution in a scalable manner using MEDLEY, a lightweight, event-driven platform
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Akram, Mohammad Salman. "Managing Changes to Service Oriented Enterprises." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/33453.
Full textAbstract:
In this thesis, we present a framework for managing changes in service oriented enterprises (SOEs). A service oriented enterprise outsources and composes its functionality from third-party Web service providers. We focus on changes initiated or triggered by these member Web services. We present a taxonomy of changes that occur in service oriented enterprises. We use a combination of several types of Petri nets to model the triggering changes and ensuing reactive changes. The techniques presented in our thesis are implemented in WebBIS, a prototype for composing and managing e-business Web services. Finally, we conduct an extensive simulation study to prove the feasibility of
the proposed techniques.Master of Science
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Midouni, Sid Ahmed Djallal. "Une approche orientée service pour la recherche sémantique de contenus multimédias." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI056/document.
Full textAbstract:
Les sources de données multimédias provenant de divers domaines (médical, tourisme, commerce, art et culture, etc.) sont devenues incontournables sur le web. L’accès à ces sources multimédias dans les systèmes distribués pose de nouveaux problèmes en raison de nombreux paramètres : volumétrie, diversité des interfaces, format de représentation, localisation, etc. En outre, l’exigence de plus en plus forte des utilisateurs et des applications à vouloir intégrer la sémantique dans la recherche d’information pose de nouvelles questions à résoudre. Pour prendre en compte cette nouvelle complexité, nous nous intéressons dans notre travail de recherche aux solutions d’intégration de données basées sur les services web. Dans cette thèse, nous proposons une approche orientée service pour la recherche sémantique de contenus multimédia. Nous avons appelé cette approche SeSaM (Semantic Search of Multimedia content). SeSaM repose sur la définition d’un nouveau type de services accédant aux contenus multimédias, qui est les services MaaS (Multimedia as a Services). Elle est basée sur un processus en deux phases : description et découverte des services MaaS. En ce qui concerne la description de services MaaS, nous avons défini le langage SA4MaaS (Semantic Annotation for MaaS services), qui est une extension de SAWSDL (recommandation W3C). L’idée principale de ce langage est l’intégration, en plus de la sémantique métier, de la sémantique de l’information multimédia dans la description des services MaaS. En ce qui concerne la découverte de services MaaS, nous avons proposé un nouveau matchmaker MaaS-MX (MaaS services Matchmaker) adapté au modèle de description des MaaS. MaaS-MX est composé de deux étapes primordiales : appariement métier et appariement multimédia. L’appariement métier consiste à comparer la description métier des services et de la requête, tandis que l’appariement multimédia compare la description multimédia des services et de la requête. L’approche a été prototypée et évaluée dans deux domaines différents : médical et tourisme. Les résultats indiquent que l’utilisation de l’appariement métier et l’appariement multimédia a considérablement amélioré les performances des systèmes de recherche de données multimédiasMultimedia data sources from various fields (medical, tourism, trade, art and culture, etc.) became essential on the web. Accessing to multimedia data in distributed systems poses new challenges due to many system parameters: volume, diversity of interfaces, representation format, location, etc. In addition, the growing needs of users and applications to incorporate semantics in the information retrieval pose new issues. To take into account this new complexity, we are interested in our research of data integration solutions based on web services. In this thesis, we propose an approach-oriented service for the semantic search of multimedia content. We called this approach SeSaM (Semantic Search of Multimedia content). SeSaM is based on the definition of a new pattern of services to access multimedia content, which is the MaaS services (Multimedia as a Services). It is based on a two-phase process: description and discovery of MaaS services. As for the MaaS services description, we have defined the SA4MaaS language (Semantic Annotation for MaaS services), which is an extension of SAWSDL (W3C recommendation). The main idea of this language is the integration, in addition to business domain semantic, of multimedia information semantics in the MaaS services description. As for the MaaS service discovery, we have proposed a new matchmaker MaaS-MX (MaaS services Matchmaker) adapted to the MaaS services description model. MaaS-MX is composed of two essential steps: domain matching and multimedia matching. Domain matching consists in comparing the business domain description of MaaS services and the query, whereas multimedia matching compares the multimedia description of MaaS services and the query. The approach has been implemented and evaluated in two different domains: medical and tourism. The results indicate that using both domain and multimedia matching considerably improves the performance of multimedia data retrieving systems
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Kattepur, Ajay. "Gestion Flexible de la Qualité de Service dans les Orchestrations de Services Web." Phd thesis, Université Rennes 1, 2012. http://tel.archives-ouvertes.fr/tel-00756048.
Full textAbstract:
Les services Web sont des applications logicielles avec des implémentations hétérogènes, dont les interfaces et les incarnations peuvent être définis, décrits et découverts sur un réseau. Une orchestration de tels services Web fournit un flux de contrôle centralisé pour les services composites, qui peuvent invoquer d'autres services en utilisant une série de constructions (séquentielle, parallèle, avec des timeouts par exemple). L'objectif de cette thèse est d'étudier l'effet des paramètres de Qualité de Service (QoS) dans la performance et les obligations contractuelles de ces orchestrations. Tout d'abord, nous générons un modèle précis pour étudier la QoS probabiliste multi-dimensionnelle dans les services Web. Lorsque la dépendance des données est présente dans les orchestrations, les conditions pour assurer la monotonie sont nécessaires et sont intégrées. Nous présentons une algèbre riche pouvant gérer plusieurs dimensions de la QoS et fournir une composition de contrat probabiliste. Une conséquence de cela est l'entrelacement des paramètres de QoS en spécifications fonctionnelles des orchestrations, qui peut fournir d'autres fonctionnalités intéressantes comme l'ordonnancement causal d'un flux de contrôle d'orchestration. Ensuite, nous étudions les effets de ces modèles de QoS sur la gestion améliorée des SLAs (Service Level Agreement). Les applications de cette architecture de gestion de la QoS sont diverses et comprennent la prise en compte de la variabilité au sein de la gamme de produits, des progiciels mathématiques pour la prise de décision, des techniques de simulation avancées pour quantifier les contrats et des protocoles de négociation améliorés. Certaines de ces techniques sont implémentées au dessus d'Orc, un langage de programmation concurrente ayant des constructions pour gérer plusieurs aspects de spécifications d'orchestration.
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Azmeh, Hamoui Zeina. "A Web service selection framework for an assisted SOA." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20097/document.
Full textAbstract:
Un service Web est un moyen d'offrir des fonctionnalités sur un réseau en utilisant des normes ouvertes pour la description et l'invocation. Les services Web représentent une réalisation importante de l'Architecture Orientée Service (AOS), à l'aide de qui, les applications peuvent être développées rapidement avec un coût bas par couplage faible les services sur un réseau. Cela nécessite la découverte et la composition des ensembles de services interopérables, selon certaines exigences fonctionnelles et non fonctionnelles. Les services Web confrontent de nombreux défis quant à leur découverte et sélection, en raison de plusieurs facteurs tels que: le nombre important de services, le manque de registres publics capables d'offrir des mécanismes efficaces de récupération de service, de leur nature dynamique qui impose divers aspects de QoS tels que la disponibilité, le temps de réponse, etc, et le manque de sémantique dans leurs descriptions d'interface. Dans cette thèse, nous avons deux objectifs principaux. Notre premier objectif est de faciliter la sélection des services Web et d'assurer la continuité du service dans des compositions de services Web. Par conséquent, nous proposons une approche basée sur l'analyse formelle de concepts (AFC) pour classer les services Web dans un premier temps par mots clés, puis par les valeurs de similarité entre leurs opérations. Cette classification est représentée comme un treillis de concepts qui révèle les relations entre les services, ce qui facilite la sélection d'un service nécessaire ainsi que l'identification des potentiels sauvegardes (substitutions en cas de panne). Notre deuxième objectif est de guider l'utilisateur en effectuant une sélection optimisée basée sur des plusieurs critères. Nous définissons un descripteur pour l'utilisateur qui spécifie des exigences fonctionnelles et non fonctionnelles. Dans ce descripteur, les propriétés fonctionnelles sont spécifiées comme un ensemble de mots-clés. Les propriétés non fonctionnelles représentent les niveaux attendus de QoS (bon, mauvais, moyen, ..) ainsi que la composition de services exprimée en tant que liens entre les propriétés fonctionnelles spécifiées. Afin d'atteindre cet objectif, nous proposons une approche basée sur l'analyse relationnelle de concepts (ARC) qui classifie les services Web en treillis de concepts similaires à la AFC, mais enrichis avec les propriétés non-fonctionnelles. Nous proposons également un mécanisme permettant d'interroger le concept de treillis résultant basée sur RCA, selon les exigences spécifiées dans le descripteur. Nous avons validé notre proposition en utilisant des services Web réels extraits de Service-Finder et Seekda (des moteurs de recherche de services Web). Pour l'approche basée sur la AFC, nous avons récupéré un total de 145 services Web que nous avons classés en fonction de leur fonctionnalité. Nous avons montré comment sélectionner efficacement un service offrant les fonctionnalités requises et la manière d'identifier ses sauvegardes. Pour l'approche basée sur RCA, nous avons récupéré 901 services Web que nous avons classés selon leur niveau de QoS et de composabilité. Nous avons vérifié que cette approche permet une sélection efficace des services correspondant aux exigences fonctionnelles et non fonctionnelles spécifiéesA Web service is a way of offering functionality over a network using open standards for description and invocation. Web services represent an important realization of Service-Oriented Architectures (SOA), using which, applications can be developed rapidly with a low cost by loosely coupling services over a network. This necessitates discovering and composing sets of interoperable services, according to some functional and non-functional requirements.Web services face many challenges regarding their discovery and selection, due to several factors like: the fairly large number of services, the lack of public registries capable of offering efficient service retrieval mechanisms, their dynamic nature which imposes various QoS aspects such as availability, response time, etc., and the lack of semantics in their interface descriptions.In this thesis, we have two main objectives. Our first objective is to facilitate Web service selection and assure service continuity in Web service compositions. Therefore, we propose an approach based on Formal Concept Analysis (FCA) to classify Web services first by keywords then by similarity values between their operations. This classification is represented as a concept lattice that reveals the relations between the services, which facilitates the selection of a needed service as well as the identification of its potential backups (substitution in case of failure).Our second objective is to guide the user towards performing an optimized multi-criteria based selection. We define a user requirements descriptor that specifies the needed functional and non-functional properties. Inside this descriptor, functional properties are specified as a set of keywords. Non-functional properties represent the expected QoS levels (good, bad, medium, ..) as well as the composition of services expressed as links between the specified functional properties. In order to meet this objective, we propose an approach based on Relational Concept Analysis (RCA) that classifies Web services into concept lattices similar to FCA, but enriched with the non-functional properties. We also propose a mechanism to query the resulting RCA-based concept lattices, according to the requirements specified in the descriptor.We validated our proposition using real Web services retrieved from Service-Finder and Seekda Web service search engines. For the FCA-based approach, we retrieved a total of 145 Web services that we classified by their functionality. We showed how to select efficiently a service offering the required functionality and how to identify its backups.For the RCA-based approach, we retrieved 901 Web services that we classified by their QoS and composability levels. We verified that the approach allows an efficient selection of services corresponding to the specified functional and non-functional requirements