Les nœuds et les liens du réseau Internet : approche géographique, économique, et technique

International audienceNodes and links of the Internet: a geographical, economic and technical approach (9 fig., 3 tabl.)This study, based on technical, economical, geographical and even historical parameters, seeks to explain the relationship between Internet networks and territorial development. The authors attempt to understand the complexity of the Internet through its links, nodes, crossroads and flows. They also identify the keys players in the Internet system and find that the geography of the net is concentrated in the triad countries. As a result, the authors highlight how technologies, actors' strategies and territorial realities are relevant components in the geography of “cyberspace”.Cette analyse, qui s'appuie sur des données techniques, économiques, géographiques mais aussi historiques, cherche à expliquer les relations entre le réseau Internet et le développement territorial. Les auteurs souhaitent comprendre la complexité d'Internet à travers ses liens, ses nœuds, ses carrefours, et ses flux. Ils identifient également les acteurs clés qui agissent au cœur du système Internet et réalisent que la géographie du réseau se concentre principalement sur les pays de la Triade. Ainsi, les auteurs montrent comment la technologie, les stratégies d'acteurs et les réalités territoriales constituent des éléments essentiels permettant d'expliquer la géographie du «cyberespace»

Reshaping the African Internet: From scattered islands to a connected continent

There is an increasing awareness amongst developing regions on the importance of localizing Internet traffic in the quest for fast, affordable, and available Internet access. In this paper, we focus on Africa, where 37 IXPs are currently interconnecting local ISPs, but mostly at the country level. An option to enrich connectivity on the continent and incentivize content providers to establish presence in the region is to interconnect ISPs present at isolated IXPs by creating a distributed IXP layout spanning the continent. The goal of this paper is to investigate whether such IXP interconnection would be possible, and if successful, to estimate the best-case benefits that could be realized in terms of traffic localization and performance. Our hope is that quantitatively demonstrating the benefits will provide incentives for ISPs to intensify their peering relationships in the region. However, it is challenging to estimate this best-case scenario, due to numerous economic, political, and geographical factors influencing the region. Towards this end, we begin with a thorough analysis of the environment in Africa. We then investigate a naive approach to IXP interconnection, which shows that a theoretically optimal solution would be infeasible in practice due to the prevailing socio-economic conditions in the region. We therefore provide an innovative, realistic four-step interconnection scheme to achieve the distributed IXP layout that considers and parameterizes external socio-economic factors using publicly available datasets. We demonstrate that our constrained solution doubles the percentage of continental intra-African paths, reduces their lengths, and drastically decreases the median of their RTTs as well as RTTs to ASes hosting the top 10 global and top 10 regional Alexa websites. Our approach highlights how, given real-world constraints, a solution requires careful considerations in order to be practically realizable.Rodérick Fanou was partially supported by IMDEA Networks Institute, US NSF grant CNS-1414177, and the project BRADE (P2013/ICE-2958) from the Directorate General of Universities and Research, Board of Education, Madrid Regional Governement. Francisco Valera was partially funded by the European Commission under FP7 project LEONE (FP7-317647). Amogh Dhamdhere was partially funded by US NSF grants CNS-1414177 and CNS-1513847.Publicad

A Polyhedral Approximation Framework for Convex and Robust Distributed Optimization

In this paper we consider a general problem set-up for a wide class of convex and robust distributed optimization problems in peer-to-peer networks. In this set-up convex constraint sets are distributed to the network processors who have to compute the optimizer of a linear cost function subject to the constraints. We propose a novel fully distributed algorithm, named cutting-plane consensus, to solve the problem, based on an outer polyhedral approximation of the constraint sets. Processors running the algorithm compute and exchange linear approximations of their locally feasible sets. Independently of the number of processors in the network, each processor stores only a small number of linear constraints, making the algorithm scalable to large networks. The cutting-plane consensus algorithm is presented and analyzed for the general framework. Specifically, we prove that all processors running the algorithm agree on an optimizer of the global problem, and that the algorithm is tolerant to node and link failures as long as network connectivity is preserved. Then, the cutting plane consensus algorithm is specified to three different classes of distributed optimization problems, namely (i) inequality constrained problems, (ii) robust optimization problems, and (iii) almost separable optimization problems with separable objective functions and coupling constraints. For each one of these problem classes we solve a concrete problem that can be expressed in that framework and present computational results. That is, we show how to solve: position estimation in wireless sensor networks, a distributed robust linear program and, a distributed microgrid control problem.Comment: submitted to IEEE Transactions on Automatic Contro

The Future of Work In Cities

The latest report in our City of the Future series examines societal shifts and advancements in technology that are impacting the rapidly changing American workforce. The report outlines solutions to help city leaders plan for the fast-approaching future, while forecasting the economic viability of two distinct sectors – retail and office administration – in which a quarter of Americans are currently employed

Réseaux de capteurs ubiquitous dans l'environnement NGN

Ubiquités Sensor Network (USN) is a conceptual network built over existing physical networks. It makes use of sensed data and provides knowledge services to anyone, anywhere and at anytime, and where the information is generated by using context awareness. Smart wearable devices and USNs are emerging rapidly providing many reliable services facilitating people life. Those very useful small end terminals and devices require a global communication substrate to provide a comprehensive global end user service. In 2010, the ITU-T provided the requirements to support USN applications and services in the Next Génération Network (NGN) environment to exploit the advantages of the core network. One of the main promising markets for the USN application and services is the e-Health. It provides continuous patients’ monitoring and enables a great improvement in medical services. On the other hand, Vehicular Ad-Hoc NETwork (VANET) is an emerging technology, which provides intelligent communication between mobile vehicles. Integrating VANET with USN has a great potential to improve road safety and traffic efficiency. Most VANET applications are applied in real time and they are sensitive to delay, especially those related to safety and health. In this work, we propose to use IP Multimedia Subsystem (IMS) as a service controller sub-layer in the USN environment providing a global substrate for a comprehensive end-to-end service. Moreover, we propose to integrate VANETs with USN for more rich applications and facilities, which will ease the life of humans. We started studying the challenges on the road to achieve this goalUbiquitous Sensor Network (USN) est un réseau conceptuel construit sur des réseaux physiques existantes. Il se sert des données détectées et fournit des services de connaissances à quiconque, n'importe où et à tout moment, et où l'information est générée en utilisant la sensibilité au contexte. Dispositifs et USN portables intelligents émergent rapidement en offrant de nombreux services fiables facilitant la vie des gens. Ces petits terminaux et terminaux très utiles besoin d'un substrat de communication globale pour fournir un service complet de l'utilisateur final global. En 2010, ITU -T a fourni les exigences pour supporter des applications et services USN dans le Next Generation Network (NGN) de l'environnement d'exploiter les avantages du réseau de base. L'un des principaux marchés prometteurs pour l'application et les services USN est la e- santé. Il fournit le suivi des patients en continu et permet une grande amélioration dans les services médicaux. D'autre part, des Véhicules Ad-hoc NETwork (VANET) est une technologie émergente qui permet une communication intelligente entre les véhicules mobiles. Intégrer VANET avec USN a un grand potentiel pour améliorer la sécurité routière et la fluidité du trafic. La plupart des applications VANET sont appliqués en temps réel et ils sont sensibles à retarder, en particulier ceux liés à la sécurité et à la santé. Dans ce travail, nous proposons d'utiliser l'IP Multimédia Subsystem (IMS) comme une sous- couche de contrôle de service dans l'environnement USN fournir un substrat mondiale pour un service complet de bout en bout. De plus, nous vous proposons d'intégrer VANETs avec USN pour des applications et des installations riches plus, ce qui facilitera la vie des humains. Nous avons commencé à étudier les défis sur la route pour atteindre cet objecti

Cross Border Innovation Economies: The Cascadia Innovation Corridor Case

In the recent literature on economic geography, cross-border regions have been highly heralded as potential sources for reaping the benefits of innovation (OECD, 2013). In fact, those regions have gained a reputation as being endowed with comparative advantages to compete in global markets (Vance, 2012). However, the types of processes that are occurring in the region, which act as hindrances (or barriers) to cross-border knowledge flows, have remained a significant but understudied topic in the academic literature. The same lack of understanding is widespread among the policy makers engaged in cross-border issues, specifically in terms of improved Cross Border Cooperation (CBC) management. This research project addresses this timely topic by evaluating the effects of the international border between Washington State, U.S. and British Columbia, Canada. This cross-border region, also known as “Cascadia,” possesses a unique combination of assets, including human capital, universities, investments, and financial capital, that enable the cross-border region’s innovation economy to compete globally (Andersen & Wenstrup, 2016). These assets have been supported by local public and private actors (Brunet-Jailly, 2008) and targeted innovation policies aimed at promoting the region as a world-class innovation hub. The object of this study is the Cascadia Innovation Corridor, a current innovation initiative in the region. I adopt a multidisciplinary approach to this case study, combining an economic geography perspective (different forms of proximity have been evaluated in the region), the border policy standpoint (governance implemented in the region) and a regional planning viewpoint (legacy of the Corridor and improvements to the overall strategy to strengthen the collaboration across the border). The research focuses on how tech economies are driving local economic development in Cascadia. This in-depth analysis pursues two goals, both of which are timely contributions to regional efforts: first, identifying the main drivers and hindrances affecting cross-border innovation linkages in the region; and second, developing policy recommendations that will support tighter cross-border economic cooperation. This project is based on primary data collected through a survey and interviews as well as secondary data gathered by official documents (e.g. Memorandum of Understanding further recalled), local newspapers and organizations’ reports. The work empirically gauges the ongoing degree of economic interactions in Cascadia on both sides of the border, examining the networks that exist between organizations and actors involved in the cross-border ecosystem, as well as the missing links that impede stronger collaboration. The final part of the analysis digs into the regional planning practices in the cross-border context and establishes a set of policy recommendations targeted at the cross-border cooperation process in Cascadia. This analysis confirms that the Cascadia innovation ecosystem possesses the key assets needed to ensure long-term growth. Moreover, it sheds light on the role of multinational companies which play a pivotal role in the Cascadia innovation ecosystem, which in turn still appears very ii fragmented. The analysis of the hindrances confirms that transportation infrastructure represents a shortcoming for regional development. From a policy standpoint, the federal-level U.S. political climate does create a burden impacting the economic linkages across the border in Cascadia. Finally, the analysis suggests that the role of local (city) governments is advocated to be more efficient in creating “horizontal” relationships across the border

Development Of Location Based Services For Geocoding And Recording Road Accidents Data

This thesis explores and reviews both conceptual and technological issues associated with integrating mobile Geographic Information System (GIS) and Location Based Services (LBS); within the context of the study, road accident geocoding data collection as subject of the problem. The development approaches are discussed in this thesis from conceptual system modelling to integrating mobile-GIS and LBS middleware with the deployed map service, the developed geocoding service and data collections service. The developed system is partially based on open source software to reduce total cost of ownership for developing countries’ governments and to follow Malaysia government policy for year 2007 in adapting and developing open source solutions. The testing of the system and geocoding was carried out within the campus of Universiti Putra Malaysia. The conclusion of this research shows the LBS and mobile-GIS geocoding method have achieved improvement compared conventional method of geocoding and data collection; where each of positional errors and effort of data transferring have been reduced using these new technologies

NMC Horizon Report: 2017 Higher Education Edition

The NMC Horizon Report > 2017 Higher Education Edition is a collaborative effort between the NMC and the EDUCAUSE Learning Initiative (ELI). This 14th edition describes annual findings from the NMC Horizon Project, an ongoing research project designed to identify and describe emerging technologies likely to have an impact on learning, teaching, and creative inquiry in education. Six key trends, six significant challenges, and six important developments in educational technology are placed directly in the context of their likely impact on the core missions of universities and colleges. The three key sections of this report constitute a reference and straightforward technology-planning guide for educators, higher education leaders, administrators, policymakers, and technologists. It is our hope that this research will help to inform the choices that institutions are making about technology to improve, support, or extend teaching, learning, and creative inquiry in higher education across the globe. All of the topics were selected by an expert panel that represented a range of backgrounds and perspectives