6,463 research outputs found

    Titanic smart objects

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    An Antitrust Analysis of the Case for Wireless Network Neutrality

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    The ongoing debate about possible implementation of regulatory rules requiring “network neutrality” for wireless telecommunications services is inherently about whether to impose a prohibition on the ability of network operators to control their vertical relationships. Antitrust analysis is well suited to analyze whether a wireless network neutrality rule is socially beneficial. Implementing network neutrality rules would be akin to using a per se antitrust rule regarding vertical relationships instead of the rule of reason analysis typically applied to vertical relationships in antitrust. Per se rules are used to prevent actions that rarely, if ever, have any pro-competitive benefits, such as price-fixing agreements. Rule of reason analysis is used when there are potential efficiency gains from the actions under investigation. Some vertical practices of the wireless carriers, such as bandwidth restrictions, may appear to be anticompetitive, but may also have plausible efficiency justifications so should be judged under rule of reason analysis. Economic examination of the wireless industry shows significant competition between networks which reduces the concern about vertical relationships, but some areas that should be monitored by antitrust and regulatory authorities. We propose several regulatory changes that would likely increase wireless competition and lessen the perceived need for prophlactic network neutrality rules while at the same time allowing efficiency-enhancing vertical relationships.network neutrality, wireless internet, antitrust,

    Public Safety Applications over WiMAX Ad-Hoc Networks

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    TechNews digests: Jan - Mar 2010

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    TechNews is a technology, news and analysis service aimed at anyone in the education sector keen to stay informed about technology developments, trends and issues. TechNews focuses on emerging technologies and other technology news. TechNews service : digests september 2004 till May 2010 Analysis pieces and News combined publish every 2 to 3 month

    Performance analysis and application development of hybrid WiMAX-WiFi IP video surveillance systems

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    Traditional Closed Circuit Television (CCTV) analogue cameras installed in buildings and other areas of security interest necessitates the use of cable lines. However, analogue systems are limited by distance; and storing analogue data requires huge space or bandwidth. Wired systems are also prone to vandalism, they cannot be installed in a hostile terrain and in heritage sites, where cabling would distort original design. Currently, there is a paradigm shift towards wireless solutions (WiMAX, Wi-Fi, 3G, 4G) to complement and in some cases replace the wired system. A wireless solution of the Fourth-Generation Surveillance System (4GSS) has been proposed in this thesis. It is a hybrid WiMAX-WiFi video surveillance system. The performance analysis of the hybrid WiMAX-WiFi is compared with the conventional WiMAX surveillance models. The video surveillance models and the algorithm that exploit the advantages of both WiMAX and Wi-Fi for scenarios of fixed and mobile wireless cameras have been proposed, simulated and compared with the mathematical/analytical models. The hybrid WiMAX-WiFi video surveillance model has been extended to include a Wireless Mesh configuration on the Wi-Fi part, to improve the scalability and reliability. A performance analysis for hybrid WiMAX-WiFi system with an appropriate Mobility model has been considered for the case of mobile cameras. A security software application for mobile smartphones that sends surveillance images to either local or remote servers has been developed. The developed software has been tested, evaluated and deployed in low bandwidth Wi-Fi wireless network environments. WiMAX is a wireless metropolitan access network technology that provides broadband services to the connected customers. Major modules and units of WiMAX include the Customer Provided Equipment (CPE), the Access Service Network (ASN) which consist one or more Base Stations (BS) and the Connectivity Service Network (CSN). Various interfaces exist between each unit and module. WiMAX is based on the IEEE 802.16 family of standards. Wi-Fi, on the other hand, is a wireless access network operating in the local area network; and it is based on the IEEE 802.11 standards

    Software defined wireless network (sdwn) for industrial environment: case of underground mine

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    Avec le dĂ©veloppement continu des industries miniĂšres canadiennes, l’établissement des rĂ©seaux de communications souterrains avancĂ©s et sans fil est devenu un Ă©lĂ©ment essentiel du processus industriel minier et ceci pour amĂ©liorer la productivitĂ© et assurer la communication entre les mineurs. Cette Ă©tude vise Ă  proposer un systĂšme de communication minier en procurant une architecture SDWN (Software Defined Wireless Network) basĂ©e sur la technologie de communication LTE. Dans cette Ă©tude, les plateformes les plus importantes de rĂ©seau mobile 4G ont Ă©tĂ© Ă©tudiĂ©es, configurĂ©es et testĂ©es dans deux zones diffĂ©rentes : un tunnel de mine souterrain et un couloir intĂ©rieur Ă©troit. Également, une architecture mobile combinant SDWN et NFV (Network Functions Virtualization) a Ă©tĂ© rĂ©alisĂ©e

    Distributed Rate Allocation Policies for Multi-Homed Video Streaming over Heterogeneous Access Networks

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    We consider the problem of rate allocation among multiple simultaneous video streams sharing multiple heterogeneous access networks. We develop and evaluate an analytical framework for optimal rate allocation based on observed available bit rate (ABR) and round-trip time (RTT) over each access network and video distortion-rate (DR) characteristics. The rate allocation is formulated as a convex optimization problem that minimizes the total expected distortion of all video streams. We present a distributed approximation of its solution and compare its performance against H-infinity optimal control and two heuristic schemes based on TCP-style additive-increase-multiplicative decrease (AIMD) principles. The various rate allocation schemes are evaluated in simulations of multiple high-definition (HD) video streams sharing multiple access networks. Our results demonstrate that, in comparison with heuristic AIMD-based schemes, both media-aware allocation and H-infinity optimal control benefit from proactive congestion avoidance and reduce the average packet loss rate from 45% to below 2%. Improvement in average received video quality ranges between 1.5 to 10.7 dB in PSNR for various background traffic loads and video playout deadlines. Media-aware allocation further exploits its knowledge of the video DR characteristics to achieve a more balanced video quality among all streams.Comment: 12 pages, 22 figure
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