An eco-friendly hybrid urban computing network combining community-based wireless LAN access and wireless sensor networking

Computer-enhanced smart environments, distributed environmental monitoring, wireless communication, energy conservation and sustainable technologies, ubiquitous access to Internet-located data and services, user mobility and innovation as a tool for service differentiation are all significant contemporary research subjects and societal developments. This position paper presents the design of a hybrid municipal network infrastructure that, to a lesser or greater degree, incorporates aspects from each of these topics by integrating a community-based Wi-Fi access network with Wireless Sensor Network (WSN) functionality. The former component provides free wireless Internet connectivity by harvesting the Internet subscriptions of city inhabitants. To minimize session interruptions for mobile clients, this subsystem incorporates technology that achieves (near-)seamless handover between Wi-Fi access points. The WSN component on the other hand renders it feasible to sense physical properties and to realize the Internet of Things (IoT) paradigm. This in turn scaffolds the development of value-added end-user applications that are consumable through the community-powered access network. The WSN subsystem invests substantially in ecological considerations by means of a green distributed reasoning framework and sensor middleware that collaboratively aim to minimize the network's global energy consumption. Via the discussion of two illustrative applications that are currently being developed as part of a concrete smart city deployment, we offer a taste of the myriad of innovative digital services in an extensive spectrum of application domains that is unlocked by the proposed platform

Multimedia multicast performance analysis for 802.11n network cards

Abstract—The technical evolution of Wi-Fi networks has made it possible to attain very high speeds for delivering content to users. However multicast transmissions never received the same level of attention as unicast transmissions in the IEEE802.11n standard. In this paper, we experimentally assess the viability of employing commercially available IEEE802.11n hardware to multicast real-time multimedia content, requiring high bandwidth and low delay. We verify the performance of the leader based multicast scheme and compare it to the standard multicast scheme. I

Enabling cross layer design: adding the madwifi extensions to nsclick

Simulations have always been a very useful and powerful tool to study and develop networking protocols. ns-2 is one of the most commonly used open-source network simulators and many protocols have been evaluated with this tool. In order to bridge the gap between simulation and implementation on a real testbed, Nsclick was developed. Nsclick makes it possible to entirely reuse code between the ns-2 simulator and a testbed, based on the Click Modular Router. In the quest for high performance wireless networks, researchers have found that the layered architecture networks did not perform well enough. Therefore they focused their research on cross layer design techniques. Although using Click and the Mad-Wifi driver gives us many possibilities to design and evaluate cross layer optimizations in a testbed set up, the Nsclick platform does not support these extensions. In this paper we will introduce an extension to ns-2 which overcomes these shortcomings of the Nsclick platform. This extension makes the wireless features of the Click Modular Router available in Nsclick platform, eliminating the differences between the ns-2 simulator, within the Nsclick platform, and a real world set up

Doische/Matagne-la-Grande :poursuite des fouilles au sanctuaire gallo-romain du “Bois des Noël”.

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Doische/Matagne-la-Grande: suite et fin? des fouilles au sanctuaire gallo-romain du “Bois des Noël »

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Distributed on demand channel selection in multi channel, multi interface wireless mesh networks

In this paper we present a protocol performing on demand distributed channel selection in multi channel, multi interface wireless mesh networks, based on the exchange of control messages. The link based channel reservation happens almost instantly when data traffic is sent through the network, and does not require long term traffic profiles or measurements. The protocol is both simulated and implemented using the IEEE 802.11b/gg protocol. We show that in a raster topology, the protocol successfully optimizes the local spectrum usage at 87% of the nodes, and that globally, an equal amount of links is allocated to each of the channels used for the transport of data packets

Fagnolle/Philippeville: le site de la « Tonne de Bière » (province de Namur). Fouilles 2009

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Le site tardo-romain de « La Tonne de Bière » à Fagnolle (Philippeville, prov. Namur). Rapport des campagnes de fouilles 2009, 2010 et 2011

De 2009 à 2011, le CReA-Patrimoine de l’ULB et le Cedarc/Musée du Malgré-Tout de Treignes ont mené des fouilles au lieu-dit “La Tonne de Bière” à Fagnolle. Celles-ci ont permis la découverte d’un ensemble d’une trentaine de trous de poteaux ainsi qu’une grande fosse d’extraction de limon. Le comblement de cette fosse a subi durant la seconde moitié du IV e siècle de notre ère un enrichissement progressif formant un horizon de “terres noires”. L’étude micro-morphologique permet d’assimiler ces “terres noires” à un potager, vraisemblablement en relation avec un site d’habitat qui reste à découvrir. L’abondant matériel céramique et monétaire qui en est issu présente une grande homogénité.info:eu-repo/semantics/publishe