67,044 research outputs found

    Design and Implementation of Virtual Private Services

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    Large scale distributed applications such as electronic commerce and online marketplaces combine network access with multiple storage and computational elements. The distributed responsibility for resource control creates new security and privacy issues, which are exacerbated by the complexity of the operating environment. In order to handle policies at multiple locations, the usual tools available (firewalls and compartmented file storage) get to be used in ways that are clumsy and prone to failure. We propose a new approach, virtual private services. Our approach relies on two functional divisions. First, we split policy specification and policy enforcement, providing local autonomy within the constraints of the global security policy. Second, we create virtual security domains, each with its own security policy. Every domain has an associated set of privileges and permissions restricting it to the resources it needs to use and the services it must perform. Virtual private services ensure security and privacy policies are adhered to through coordinated policy enforcement points. We describe our architecture and a prototype implementation, and present a preliminary performance evaluation confirming that our overhead of policy enforcement using is small

    Agent fabrication and its implementation for agent-based electronic commerce

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    In the last decade, agent-based e-commerce has emerged as a potential role for the next generation of e-commerce. How to create agents for e-commerce applications has become a serious consideration in this field. This paper proposes a new scheme named agent fabrication and elaborates its implementation in multi-agent systems based on the SAFER (Secure Agent Fabrication, Evolution & Roaming) architecture. First, a conceptual structure is proposed for software agents carrying out e-commerce activities. Furthermore, agent module suitcase is defined to facilitate agent fabrication. With these definitions and facilities in the SAFER architecture, the formalities of agent fabrication are elaborated. In order to enhance the security of agent-based e-commerce, an infrastructure of agent authorization and authentication is integrated in agent fabrication. Our implementation and prototype applications show that the proposed agent fabrication scheme brings forth a potential solution for creating agents in agent-based e-commerce applications

    Challenges to describe QoS requirements for web services quality prediction to support web services interoperability in electronic commerce

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    Quality of service (QoS) is significant and necessary for web service applications quality assurance. Furthermore, web services quality has contributed to the successful implementation of Electronic Commerce (EC) applications. However, QoS is still the big issue for web services research and remains one of the main research questions that need to be explored. We believe that QoS should not only be measured but should also be predicted during the development and implementation stages. However, there are challenges and constraints to determine and choose QoS requirements for high quality web services. Therefore, this paper highlights the challenges for the QoS requirements prediction as they are not easy to identify. Moreover, there are many different perspectives and purposes of web services, and various prediction techniques to describe QoS requirements. Additionally, the paper introduces a metamodel as a concept of what makes a good web service

    Pendekatan konstruktif dalam inovasi pengajaran dan pembelajaran Bahasa Melayu di Kolej Vokasional

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    Pendekatan konstruktif adalah pendekatan pengajaran dan pembelajaran yang berpusatkan pelajar manakala inovasi pengajaran pula dikaitkan dengan kaedah pengajaran yang terbaru demi mengukuhkan pemahaman pelajar. Pembelajaran berasaskan pendekatan konstruktif merupakan elemen yang penting dan perlu difahami oleh guru-guru bagi memantapkan proses pengajaran dan pembelajaran sesuai dengan peredaran masa dan menjayakan proses tranformasi pendidikan negara. Objektif kajian ini dijalankan untuk mengenal pasti pemahaman guru-guru bahasa Melayu berkaitan inovasi, mengenal pasti perbezaan yang wujud antara guru lelaki dan guru perempuan dalam mengamalkan inovasi, pengkaji juga melihat adakah wujud perbezaan antara guru baru dan guru yang sudah berpengalaman dalam aspek mengaplikasikan inovasi serta mengenal pasti kekangan-kekangan yang dialami oleh para guru untuk mengaplikasikan inovasi di sekolah. Seramai 63 orang guru bahasa Melayu dari lapan buah kolej vokasional telah dipilih sebagai responden dalam kajian ini. Data dianalisis menggunakan perisian Winsteps 3.69.1.11 dengan pendekatan Model Pengukuran Rasch. Hasil analisis menunjukkan bahawa guru�guru bahasa Melayu memahami kepentingan inovasi dalam pengajaran dan pembelajaran. Hasil kajian juga menunjukkan guru-guru perempuan lebih banyak menerapkan unsur inovasi dalam pengajaran berbanding guru lelaki. Walaupun begitu, aspek pengalaman tidak menunjukkan perbezaan dari segi pengamalan inovasi sama ada guru baru ataupun guru yang sudah berpengalaman. Pengkaji juga mengenal pasti beberapa kekangan yang dialami oleh guru-guru untuk mengamalkan inovasi ini. Sebagai langkah untuk menangani masalah berkenaan, beberapa cadangan telah dikemukakan oleh pengkaji bagi memastikan guru-guru dapat merealisasikan proses pengajaran berkesan dengan penerapan inovasi mengikut model pendekatan konstruktif. Pengkaji berharap, kajian ini dapat dijadikan sebagai satu panduan kepada pelaksana kurikulum bagi memastikan budaya inovasi sentiasa menjadi amalan dalam kalangan guru demi mengangkat profesionalisme guru di Malaysia

    webXice: an Infrastructure for Information Commerce on the WWW

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    Systems for information commerce on the WWW have to support flexible business models if they should be able to cover a wide range of requirements imposed by the different types of information businesses. This leads to non-trivial functional and security requirements both on the provider and consumer side, for which we introduce an architecture and a system implementation, webXice. We focus on the question, how participants with minimal technological requisites, i.e. solely standard Web browsers available, can be technologically enabled to articipate in the information commerce at a system level, while not sacrificing the functionality and security required by an autonomous participant in an information commerce scenario. In particular, we propose an implementation strategy to efficiently support persistent message logging for light-weight clients, that enables clients to collect and manage non-reputiable messages as proofs. We believe that the capability to support minimal system platforms is a necessary precondition for the wide-spread use of any information commerce infrastructure
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