4,282 research outputs found

    Mobile Computing in Digital Ecosystems: Design Issues and Challenges

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    In this paper we argue that the set of wireless, mobile devices (e.g., portable telephones, tablet PCs, GPS navigators, media players) commonly used by human users enables the construction of what we term a digital ecosystem, i.e., an ecosystem constructed out of so-called digital organisms (see below), that can foster the development of novel distributed services. In this context, a human user equipped with his/her own mobile devices, can be though of as a digital organism (DO), a subsystem characterized by a set of peculiar features and resources it can offer to the rest of the ecosystem for use from its peer DOs. The internal organization of the DO must address issues of management of its own resources, including power consumption. Inside the DO and among DOs, peer-to-peer interaction mechanisms can be conveniently deployed to favor resource sharing and data dissemination. Throughout this paper, we show that most of the solutions and technologies needed to construct a digital ecosystem are already available. What is still missing is a framework (i.e., mechanisms, protocols, services) that can support effectively the integration and cooperation of these technologies. In addition, in the following we show that that framework can be implemented as a middleware subsystem that enables novel and ubiquitous forms of computation and communication. Finally, in order to illustrate the effectiveness of our approach, we introduce some experimental results we have obtained from preliminary implementations of (parts of) that subsystem.Comment: Proceedings of the 7th International wireless Communications and Mobile Computing conference (IWCMC-2011), Emergency Management: Communication and Computing Platforms Worksho

    FastM: Design and Evaluation of a Fast Mobility Mechanism for Wireless Mesh Networks

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    Although there is a large volume of work in the literature in terms of mobility approaches for Wireless Mesh Networks, usually these approaches introduce high latency in the handover process and do not support realtime services and applications. Moreover, mobility is decoupled from routing, which leads to inefficiency to both mobility and routing approaches with respect to mobility. In this paper we present a new extension to proactive routing protocols using a fast mobility extension, FastM, with the purpose of increasing handover performance in Wireless Mesh Networks. With this new extension, a new concept is created to integrate information between neighbor wireless mesh routers, managing locations of clients associated to wireless mesh routers in a certain neighborhood, and avoiding packet loss during handover. The proposed mobility approach is able to optimize the handover process without imposing any modifications to the current IEE 802.11 MAC protocol and use unmodified clients. Results show the improved efficiency of the proposed scheme: metrics such as disconnection time, throughput, packet loss and control overhead are largely improved when compared to previous approaches. Moreover, these conclusions apply to mobility scenarios, although mobility decreases the performance of the handover approach, as expected

    A Literature Survey of Cooperative Caching in Content Distribution Networks

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    Content distribution networks (CDNs) which serve to deliver web objects (e.g., documents, applications, music and video, etc.) have seen tremendous growth since its emergence. To minimize the retrieving delay experienced by a user with a request for a web object, caching strategies are often applied - contents are replicated at edges of the network which is closer to the user such that the network distance between the user and the object is reduced. In this literature survey, evolution of caching is studied. A recent research paper [15] in the field of large-scale caching for CDN was chosen to be the anchor paper which serves as a guide to the topic. Research studies after and relevant to the anchor paper are also analyzed to better evaluate the statements and results of the anchor paper and more importantly, to obtain an unbiased view of the large scale collaborate caching systems as a whole.Comment: 5 pages, 5 figure

    Securing route optimisation in NEMO

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    Third International Symposium on Modeling and Optimization in Mobile, Ad Hoc,and Wireless Networks. 4-6 April 2005. Riva del Garda, Trentino, ItalyThe network mobility (NEMO) basic support protocol enables mobile networks to change their point of attachment to the Internet, while preserving established sessions of the nodes within the mobile network. When only a nonnested mobile network is considered, the so-called triangle routing is the main problem that should be faced. In mobile IPv6, the route optimisation mechanism solves this problem, and the return routability mechanism aims to limit the security concerns originated because of the route optimisation. Nowadays return routability is considered a weak solution (i.e., based on strong assumptions). In this article we explore different approaches to route optimisation in NEMO and we devise how to adapt some of the terminal mobility solutions to a NEMO environment, where, as we propose, a delegation of signalling rights from the mobile network node to the mobile router is necessary.Publicad

    Multinet : enabler for next generation enterprise wireless services

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    Wireless communications are currently experiencing a fast migration toward the beyond third-generation (B3G)/fourth generation (4G) era. This represents a generational change in wireless systems: new capabilities related to mobility and new services support is required and new concepts as individual-centric, user-centric or ambient-aware communications are included. One of the main restrictions associated to wireless technology is mobility management, this feature was not considered in the design phase; for this reason, a complete solution is not already found, although different solutions are proposed and are being proposed. In MULTINET project, features as mobility and multihoming are applied to wireless network to provide the necessary network and application functionality enhancements for seamless data communication mobility considering end-user scenario and preferences. The aim of this paper is to show the benefits of these functionalities from the Service Providers and final User point of view

    A Marketplace for Efficient and Secure Caching for IoT Applications in 5G Networks

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    As the communication industry is progressing towards fifth generation (5G) of cellular networks, the traffic it carries is also shifting from high data rate traffic from cellular users to a mixture of high data rate and low data rate traffic from Internet of Things (IoT) applications. Moreover, the need to efficiently access Internet data is also increasing across 5G networks. Caching contents at the network edge is considered as a promising approach to reduce the delivery time. In this paper, we propose a marketplace for providing a number of caching options for a broad range of applications. In addition, we propose a security scheme to secure the caching contents with a simultaneous potential of reducing the duplicate contents from the caching server by dividing a file into smaller chunks. We model different caching scenarios in NS-3 and present the performance evaluation of our proposal in terms of latency and throughput gains for various chunk sizes
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