96 research outputs found

    40 Gbps Access for Metro networks: Implications in terms of Sustainability and Innovation from an LCA Perspective

    Full text link
    In this work, the implications of new technologies, more specifically the new optical FTTH technologies, are studied both from the functional and non-functional perspectives. In particular, some direct impacts are listed in the form of abandoning non-functional technologies, such as micro-registration, which would be implicitly required for having a functioning operation before arrival the new high-bandwidth access technologies. It is shown that such abandonment of non-functional best practices, which are mainly at the management level of ICT, immediately results in additional consumption and environmental footprint, and also there is a chance that some other new innovations might be 'missed.' Therefore, unconstrained deployment of these access technologies is not aligned with a possible sustainable ICT picture, except if they are regulated. An approach to pricing the best practices, including both functional and non-functional technologies, is proposed in order to develop a regulation and policy framework for a sustainable broadband access.Comment: 10 pages, 6 Tables, 1 Figure. Accepted to be presented at the ICT4S'15 Conferenc

    Évolution du protocole GTP dans un contexte de VPN et de mobilité-IP

    Get PDF
    Définitions et concepts de base -- Éléments de la problématique -- Objectifs de la recherche -- Plan du mémoire -- Analyse du protocole GTP -- Réseau mobile IP basé sur MPLS -- Mobilité basée sur les technologies VPN -- Gestion de mobilité tout-IP -- Concepts complémentaires de mobilité et d'intégration VPN -- Améliorations proposées au protocole GTP -- Fondements des améliorations proposées -- Évolution proposée de GTP -- Le diagramme de séquence des messages -- Résultats expérimentaux et analytiques -- Environnement de simulation -- Plan d'expérience -- Expérimentation et analyse des résultats -- Conclusion -- synthèse des travaux -- Limitations principales -- Indications pour des recherches futures

    Challenges and complexities in application of LCA approaches in the case of ICT for a sustainable future

    Get PDF
    In this work, three of many ICT-specific challenges of LCA are discussed. First, the inconsistency versus uncertainty is reviewed with regard to the meta-technological nature of ICT. As an example, the semiconductor technologies are used to highlight the complexities especially with respect to energy and water consumption. The need for specific representations and metric to separately assess products and technologies is discussed. It is highlighted that applying product-oriented approaches would result in abandoning or disfavoring of new technologies that could otherwise help toward a better world. Second, several believed-untouchable hot spots are highlighted to emphasize on their importance and footprint. The list includes, but not limited to, i) User Computer-Interfaces (UCIs), especially screens and displays, ii) Network-Computer Interlaces (NCIs), such as electronic and optical ports, and iii) electricity power interfaces. In addition, considering cross-regional social and economic impacts, and also taking into account the marketing nature of the need for many ICT's product and services in both forms of hardware and software, the complexity of End of Life (EoL) stage of ICT products, technologies, and services is explored. Finally, the impact of smart management and intelligence, and in general software, in ICT solutions and products is highlighted. In particular, it is observed that, even using the same technology, the significance of software could be highly variable depending on the level of intelligence and awareness deployed. With examples from an interconnected network of data centers managed using Dynamic Voltage and Frequency Scaling (DVFS) technology and smart cooling systems, it is shown that the unadjusted assessments could be highly uncertain, and even inconsistent, in calculating the management component's significance on the ICT impacts.Comment: 10 pages. Preprint/Accepted of a paper submitted to the ICT4S Conferenc

    Gas sensing with SU-8 whispering gallery mode resonators

    Get PDF
    We present an optical gas sensor using SU-8 microdisk whispering gallery mode resonators. Sensitivities were measured for different vapor phases: water, toluene, limonene and valeric acid. The highest reported sensitivity is 18.98 pm/ppm

    All-polymer whispering gallery mode resonators for gas sensing

    Get PDF
    Sensitivity of polymeric microdisks is evaluated for selected compounds in their vapor phase such as humidity, isopropanol, toluene, limonene, 1-butanol, and pentanoic acid (valeric acid). Among these compounds, pentanoic acid exhibits the highest sensitivity (23 pm/ppm) with a limit of detection estimated to be around 0.6 ppm. We are interested in the contribution of the geometry deformation due to polymer swelling on the sensitivity as it may be engineered to improve performance of gas sensing devices. Experimental observations show a trend where sensitivity to humidity increased with the ratio of the undercut over the radius of the microcavity
    • …
    corecore