Initially, Grid technologies were principally associated with supercomputer centres and large-scale scientific applications in physics and astronomy. They are now increasingly seen as being relevant to many areas of e-Science and e-Business. The emergence of the Open Grid Services Architecture (OGSA), to complement the ongoing activity on Web Services standards, promises to provide a service-based platform that can meet the needs of both business and scientific applications. Early Grid applications focused principally on the storage, replication and movement of file-based data. Now the need for the full integration of database technologies with Grid middleware is widely recognized. Not only do many Grid applications already use databases for managing metadata, but increasingly many are associated with large databases of domain-specific information (e.g. biological or astronomical data). This paper describes the design and implementation of OGSA-DAI, a service-based architecture for database access over the Grid. The approach involves the design of Grid Data Services that allow consumers to discover the properties of structured data stores and to access their contents. The initial focus has been on support for access to Relational and XML data, but the overall architecture has been designed to be extensible to accommodate

Dynasoar is an infrastructure for dynamically deploying Web Services over a Grid or the Internet. It enables an approach to Grid computing in which distributed applications are built around services instead of jobs. Dynasoar automatically deploys a service on an available host if no existing deployments exist, or if performance requirements cannot be met by existing deployments. This is analogous to remote job scheduling, but offers the opportunity for improved performance as the cost of moving and deploying the service can be shared across the processing of many messages. A key feature of the architecture is that it makes a clear separation between Web Service Providers, who offer services to consumers, and Host Providers, who offer computational resources on which services can be deployed, and messages sent to them processed. Separating these two components and defining their interactions, opens up the opportunity for interesting new organisational / business models. 1.

This paper describes an architecture for dynamically deploying Web Services over a grid or the Internet. Distributed job scheduling systems are found at the heart of most grid computing infrastructures. They allow jobs (a combination of the code to be executed and (in many cases) the data on which it is to operate) to be created by clients and dynamically routed to available, remote computing resources for execution. In recent years, there has been a trend towards utilising Web Services to build grid and other distributed applications. An application is represented as a set of services that communicate through the exchange of messages. However, if the computational requirements of a service cannot be met by its hosting environment then a job must be created and sent to a distributed job scheduling system for execution on a suitable host. Therefore, application writers must deal with the complexity of managing two different types of computational entities: services and jobs. The Dynasoar project is investigating an alternative approach in which there are no jobs, but only services. A service can be dynamically deployed on an available host in order to utilise its computational power, if

Abstract. The penetration of Adaptive Educational Hypermedia (AEH) within the educational community has been very poor so far. In part this is due to the complexity of the authoring process. But it also influenced by the often short ‘lifetime ’ of the AEH software itself. We see AEH system interoperability as a route to address these problems. This paper builds on previous limited interoperability work, between the AEH systems MOT and WHURLE, by using open web standards. We describe a Web Service using Web Services Description Language and SOAP that is capable of converting MOT materials to WHURLE. Moreover this Web Service is flexible and easily extensible, and we hope that this will mark the first step in developing an interoperable middleware for AEH conversions. 1

Testing mobile applications that run on handheld devices is challenging because it is relatively new, and problems show up in new ways. This thesis presents a risk catalog that is populated with known problems and potential problems in mobile applications. The primary objective of this structured risk catalog is to serve as a test idea generator for software testers new to testing mobile applications, and to broaden the risk analysis that guides the testing of this new breed of application. A risk-based software tester can choose the categories of interest from this structured risk profile, explore the mobile application under test, and create more powerful tests designed to detect potential failures. I used a sample mobile application in the education domain to build and refine the risk catalog. Thereafter, I conducted a pilot study to determine the efficiency of this risk catalog by using it as a guide to test a real-time financial mobile application. Finally, I updated and enriched the risk catalog by building, analyzing and testing a mobile application utilizing Web services. iii Table of Contents

To my parents This research proposes a new architecture for Adaptive Educational Hypermedia Systems (AEHS). Architectures in the context of this thesis refer to the components of the system and their communications and interactions. The architecture addresses the limitations of AEHS regarding interoperability, reusability, openness, flexibility, and limited tools for collaborative and social learning. It presents an integrated adaptive and collaborative Web-based learning environment. The new e-learning environment is implemented as a set of independent Web services within a service-oriented architecture (SOA). Moreover, it uses a modern Learning Management System (LMS) as the delivery service and the user interface for this environment. This is a two-way solution, whereby adaptive learning is introduced via a widely adopted LMS, and the LMS itself is enriched with an external- yet integrated-adaptation layer. To test the relevance of the new architecture, practical experiments were undertaken.

This paper is an exhaustive review summarizing the results, observations and findings of the renowned researchers in the domain of Web Service Discovery. After extensive scavenging on the Internet, we felt that there is a paucity of good quality survey papers, which can help, provide directions to a researcher looking for a fertile area to explore in the Web Services arena, especially in Discovery of Web Services. We highlight here the list of problems, which need to be looked into and investigated. This comprehensive listing of the open-ended unresolved issues is presented in a novel way, by providing its Cause-Effect Analysis. In this paper, we hand-hold you to into a literary journey that provides a glimpse of the huge spectrum of work investigated by researchers globally in the field of Discovering the Right Services, based on the Requirements provided by the Consumer.

Web Services technology is becoming the de-facto standard for integration of legacy applications within an organisation and for cross organisation enterprise application integration (B2BEAI). Much work has gone into specifying Web Services functionality using workflow like techniques (BPEL4WS, WSCI, WSFL, XLANG) and production of software to enact such descriptions. However, most of this software relies on one central server to enact the workflow which may be a performance bottleneck when the server is under high load. In this paper we outline a workflow specification language and present a sample implementation of a workflow engine which allows distributed enactment of workflows. Distributed enactment removes this potential bottleneck and can also reduce data transfer. We also describe how the workflow engine promotes message based integration, simplifying the problem of application integration across organisational boundaries. 1.

Web Services technology is becoming the de-facto standard for integration of legacy applications within an organisation and for cross organisation enterprise application integration. Much work has gone into specifying Web Services functionality using workflow like techniques and production of software to enact such descriptions. However, most of this software relies on one central server to enact the workflow. Centralised enactment may be unattractive in inter-organisational settings and in addition, form a performance bottleneck when the server is under high load. In this paper we outline the DECS task model for workflow specification and present a prototype implementation of a distributed enactment engine based on J2EE middleware. There is a separation of concerns between the specification of the workflow and its enactment, allowing it to be deployed in a number of configurations based on performance considerations and organisational requirements. We also describe how the workflow engine promotes message based integration, simplifying the problem of application integration across organisational boundaries. 1

This research “Designing Dependable Web Services Security Architecture Solutions ” addresses