264,527 research outputs found

    Active architecture for pervasive contextual services

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    Pervasive services may be defined as services that are available to any client (anytime, anywhere). Here we focus on the software and network infrastructure required to support pervasive contextual services operating over a wide area. One of the key requirements is a matching service capable of assimilating and filtering information from various sources and determining matches relevant to those services. We consider some of the challenges in engineering a globally distributed matching service that is scalable, manageable, and able to evolve incrementally as usage patterns, data formats, services, network topologies and deployment technologies change. We outline an approach based on the use of a peer-to-peer architecture to distribute user events and data, and to support the deployment and evolution of the infrastructure itself

    Active architecture for pervasive contextual services

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    International Workshop on Middleware for Pervasive and Ad-hoc Computing MPAC 2003), ACM/IFIP/USENIX International Middleware Conference (Middleware 2003), Rio de Janeiro, Brazil This work was supported by the FP5 Gloss project IST2000-26070, with partners at Trinity College Dublin and Université Joseph Fourier, and by EPSRC grants GR/M78403/GR/M76225, Supporting Internet Computation in Arbitrary Geographical Locations, and GR/R45154, Bulk Storage of XML Documents.Pervasive services may be defined as services that are available "to any client (anytime, anywhere)". Here we focus on the software and network infrastructure required to support pervasive contextual services operating over a wide area. One of the key requirements is a matching service capable of as-similating and filtering information from various sources and determining matches relevant to those services. We consider some of the challenges in engineering a globally distributed matching service that is scalable, manageable, and able to evolve incrementally as usage patterns, data formats, services, network topologies and deployment technologies change. We outline an approach based on the use of a peer-to-peer architecture to distribute user events and data, and to support the deployment and evolution of the infrastructure itself.Peer reviewe

    Effects of population size for location-aware node placement in WMNs: evaluation by a genetic algorithm--based approach

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    Wireless mesh networks (WMNs) are cost-efficient networks that have the potential to serve as an infrastructure for advanced location-based services. Location service is a desired feature for WMNs to support location-oriented applications. WMNs are also interesting infrastructures for supporting ubiquitous multimedia Internet access for mobile or fixed mesh clients. In order to efficiently support such services and offering QoS, the optimized placement of mesh router nodes is very important. Indeed, such optimized mesh placement can support location service managed in the mesh and keep the rate of location updates low...Peer ReviewedPostprint (author's final draft

    Peer reviews: What can we learn from our students?

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    This paper describes lessons learnt whilst using an online peer review system in an undergraduate unit for pre-service teachers. In this unit students learn to use information technologies as part of their future teaching practice. The unit aims to foster graduates who become life-long reflective educators by providing opportunities to explore and reflect on how they might use technology in authentic learning situations. Whilst peer review is an appropriate activity for supporting critical thinking and reflective practice in this kind of unit, it requires a number of decisions to be made in relation to student preparation and support, implementation strategy, and technological infrastructure to make it work in specific contexts. Much research has been conducted in recent years to inform educators in making these decisions. However, there are still gaps in the research, particularly in how to improve the quality and consistency of feedback that students give to each other in their feedback. This paper describes the experiences of implementing an online peer review system aiming to improve quality and consistency of feedback. This exploration has revealed that we can learn much about ways to improve our teaching practices by giving students an opportunity to review each other’s work and give each other feedback

    Web Services –An Enabling Technology for Trading Partners Community Virtual Integration

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    The Application Service Provider (ASP) model is a widely adopted business model for communities of buyers and sellers to conduct commerce over the Internet in a virtually integrated environment. However, there are limitations imposed by the ASP model. This paper discusses how an alternative combination of peer-to-peer and web services technologies can provide a suitable, low-cost IT infrastructure that could potentially overcome these limitations and enable trading partners in a community to achieve virtual integration. Such an alternative infrastructure would allow trading partners to improve upon their resource utilisation for IT and, instead, focus on their core businesses, discover new business opportunities and form new partnerships dynamically as and when needed, in a loosely-coupled manner

    An adaptive approach to service discovery in ad hoc networks

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    Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    An adaptive approach to service discovery in ad hoc networks

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    Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI
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