74,510 research outputs found

    Holistic analysis of mix protocols

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    Security protocols are often analysed in isolation as academic challenges. However, the real world can require various combinations of them, such as a certified email protocol executed over a resilient channel, or the key registration protocol to precede the purchase protocols of Secure Electronic Transactions (SET). We develop what appears to be the first scalable approach to specifying and analysing mix protocols. It expands on the Inductive Method by exploiting the simplicity with which inductive definitions can refer to each other. This lets the human analyst study each protocol separately first, and then derive holistic properties about the mix. The approach, which is demonstrated on the sequential composition of a certification protocol with an authentication one, is not limited by the features of the protocols, which can, for example, share message components such as cryptographic keys and nonces. It bears potential for the analysis of complex protocols constructed by general composition of others

    Ethernet - a survey on its fields of application

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    During the last decades, Ethernet progressively became the most widely used local area networking (LAN) technology. Apart from LAN installations, Ethernet became also attractive for many other fields of application, ranging from industry to avionics, telecommunication, and multimedia. The expanded application of this technology is mainly due to its significant assets like reduced cost, backward-compatibility, flexibility, and expandability. However, this new trend raises some problems concerning the services of the protocol and the requirements for each application. Therefore, specific adaptations prove essential to integrate this communication technology in each field of application. Our primary objective is to show how Ethernet has been enhanced to comply with the specific requirements of several application fields, particularly in transport, embedded and multimedia contexts. The paper first describes the common Ethernet LAN technology and highlights its main features. It reviews the most important specific Ethernet versions with respect to each application field’s requirements. Finally, we compare these different fields of application and we particularly focus on the fundamental concepts and the quality of service capabilities of each proposal

    The global dimension of water governance: why the river basin approach is no longer sufficient and why cooperative action at global level is needed

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    When water problems extend beyond the borders of local communities, the river basin is generally seen as the most appropriate unit for analysis, planning, and institutional arrangements. In this paper it is argued that addressing water problems at the river basin level is not always sufficient. Many of today’s seemingly local water issues carry a (sub)continental or even global dimension, which urges for a governance approach that comprises institutional arrangements at a level beyond that of the river basin. This paper examines a number of arguments for the thesis that good water governance requires a global approach complementary to the river basin approach. Subsequently, it identifies four major issues to be addressed at global scale: Efficiency, equity, sustainability and security of water supply in a globalised world. Finally, the paper raises the question of what kind of institutional arrangements could be developed to cope with the global dimension of water issues. A few possible directions are explored, ranging from an international protocol on full-cost water pricing and a water label for water-intensive products to the implementation of water footprint quotas and the water-neutral concept

    The global dimension of water governance: Nine reasons for global arrangements in order to cope with local water problems

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    Where water problems extend beyond the borders of local communities, the catchment area or river basin is generally seen as the most appropriate unit for analysis, planning and institutional arrangements. In this paper it\ud is argued that addressing water problems at the river basin level is not always sufficient. It is shown that a substantial part of today’s water issues carries a (sub)continental or even global dimension, which urges for a governance approach that comprises coordination and institutional arrangements at a level above that of the river basin. This paper distinguishes and reviews nine developments that support this argument: • Local issues of water scarcity and flooding will be enhanced or weakened by human-induced global climate\ud change.\ud • Local problems of water pollution are often intrinsic to the structure of the global economy.\ud • There is a growing presence of multinationals in the drinking water sector.\ud • Several national governments are developing plans for large-scale inter-basin water transfers.\ud • An increasing number of water-short countries seek to preserve their domestic water resources through the\ud import of water in virtual form.\ud • Global trade in water-intensive commodities offers the opportunity of global water saving if this trade is\ud from countries with high to countries with low water productivity.\ud • The water footprints of individual people are increasingly externalised to other parts of the world, so that\ud many local water problems are strongly related to consumption elsewhere.\ud • Some people around the world have comparatively high water footprints, which raises the question of\ud whether this is fair and sustainable.\ud • Due to its increasing scarcity and uneven distribution across the globe, water is gradually becoming a geopolitical resource, influencing the power of nations.\ud The described developments raise the question of what kind of institutional arrangements could be developed to cope with the global dimension of water issues. A few possible directions are identified in an explorative analysis: an international protocol on full-cost water pricing, a water label for water-intensive products, a disposal tax on goods that will cause water pollution in their waste stage (to be used for pollution prevention and\ud control), international nutrient housekeeping, minimum water rights, maximum allowable water footprints, and tradable water footprint permits

    Compatibility of Breeding Techniques in Organic Systems

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    Introduction The rapid development of genetic engineering techniques is leading to a level of genetic disruption never experienced before. In order to safeguard organic integrity and to ensure organic food will continue to meet the highest consumer expectations in this challenging situation, IFOAM - Organics International is proposing a number of measures to be put in place to further fortify and enhance the organic sector’s available genetic resources. This position paper provides clarity and transparency on the criteria used by the organic sector as to what breeding techniques are compatible with organic systems, which techniques to exclude, and definitions on what should be considered as genetic engineering and genetically modified organisms (GMOs). We further differentiate between the criteria relevant for organic breeding as defined in the IFOAM – Organics International norms, versus the criteria for cultivars and breeds derived from nonorganic breeding programs regarding their compatibility for the use in commercial organic production and processing. The following experts are members of the IFOAM Working Group on New Plant Breeding Techniques: Michael Glos, Monika Messmer, Gebhard Rossmanith, Gunter Backes, Michael Sligh, Adrian Rodriguez-Burruezo, Heli Matilainen, Andre Leu, Louise Luttikholt, Helen Jensen, Eric Gall, Chito Medina, Krishna Prasad, Kirsten Arp

    Shaping the Global Arena: Preparing the EU Emissions Trading Scheme for the post-2012 Period. CEPS Task Force Reports No. 61, 6 March 2007

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    Having been underway for more than two years, the review of the EU Emissions Trading Scheme (EU ETS) is entering a decisive phase with the European Commission’s recent announcement that it will table formal proposals in the second half of 2007. Based on an assessment of the EU ETS, this new CEPS Task Force Report tests the performance of four different design models (a cap-and-trade system based on free allocation, benchmarks, auctioning and a credit-and-baseline system) against 10 criteria under three headings: environmental effectiveness, economic efficiency and the contribution of the ETS to achieving long-term climate change policy objectives. Based on this assessment, the report makes a number of recommendations in the area of allocation, creation of investment incentives and the merits of including new sectors and new gases. The report also addresses the particular challenge of completing the EU ETS review before a global post-2012 agreement can be reached, i.e. the EU ETS will be reviewed against an unknown global context
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