33 research outputs found

    Flexible programmable networking: A reflective, component-based approach

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    The need for programmability and adaptability in networking systems is becoming increasingly important. More specifically, the challenge is in the ability to add services rapidly, and be able to deploy, configure and reconfigure them as easily as possible. Such demand is creating a considerable shift in the way networks are expected to operate in the future. This is the main aim of programmable networking research community, and in our project we are investigating a component-based approach to the structuring of programmable networking software. Our intention is to apply the notion of components, component frameworks and reflection ubiquitously, thus accommodating all the different elements that comprise a programmable networking system

    Assessing the cost of global biodiversity and conservation knowledge

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    Knowledge products comprise assessments of authoritative information supported by stan-dards, governance, quality control, data, tools, and capacity building mechanisms. Considerable resources are dedicated to developing and maintaining knowledge productsfor biodiversity conservation, and they are widely used to inform policy and advise decisionmakers and practitioners. However, the financial cost of delivering this information is largelyundocumented. We evaluated the costs and funding sources for developing and maintain-ing four global biodiversity and conservation knowledge products: The IUCN Red List ofThreatened Species, the IUCN Red List of Ecosystems, Protected Planet, and the WorldDatabase of Key Biodiversity Areas. These are secondary data sets, built on primary datacollected by extensive networks of expert contributors worldwide. We estimate that US160million(range:US160million (range: US116–204 million), plus 293 person-years of volunteer time (range: 278–308 person-years) valued at US14million(rangeUS 14 million (range US12–16 million), were invested inthese four knowledge products between 1979 and 2013. More than half of this financingwas provided through philanthropy, and nearly three-quarters was spent on personnelcosts. The estimated annual cost of maintaining data and platforms for three of these knowl-edge products (excluding the IUCN Red List of Ecosystems for which annual costs were notpossible to estimate for 2013) is US6.5millionintotal(range:US6.5 million in total (range: US6.2–6.7 million). We esti-mated that an additional US114millionwillbeneededtoreachpredefinedbaselinesofdatacoverageforallthefourknowledgeproducts,andthatonceachieved,annualmaintenancecostswillbeapproximatelyUS114 million will be needed to reach pre-defined baselines ofdata coverage for all the four knowledge products, and that once achieved, annual mainte-nance costs will be approximately US12 million. These costs are much lower than those tomaintain many other, similarly important, global knowledge products. Ensuring that biodi-versity and conservation knowledge products are sufficiently up to date, comprehensiveand accurate is fundamental to inform decision-making for biodiversity conservation andsustainable development. Thus, the development and implementation of plans for sustain-able long-term financing for them is critical

    Shortfalls and Solutions for Meeting National and Global Conservation Area Targets

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    Governments have committed to conserving 17% of terrestrial and 10% of marine environments globally, especially “areas of particular importance for biodiversity” through “ecologically representative” Protected Area (PA) systems or other “area-based conservation measures”, while individual countries have committed to conserve 3–50% of their land area. We estimate that PAs currently cover 14.6% of terrestrial and 2.8% of marine extent, but 59–68% of ecoregions, 77–78% of important sites for biodiversity, and 57% of 25,380 species have inadequate coverage. The existing 19.7 million km2 terrestrial PA network needs only 3.3 million km2 to be added to achieve 17% terrestrial coverage. However, it would require nearly doubling to achieve, costefficiently, coverage targets for all countries, ecoregions, important sites, and species. Poorer countries have the largest relative shortfalls. Such extensive and rapid expansion of formal PAs is unlikely to be achievable. Greater focus is therefore needed on alternative approaches, including community- and privately managed sites and other effective area-based conservation measures.We are grateful to the many individuals and organizations who contribute to the IUCN Red List of Threatened Species,WDPA, or to identification of IBAs or AZEs. We thank A. Bennett for help with data collation and N. Dulvy, W. Laurance, and D. Faith for helpful comments on an earlier draft. This work was supported by the Cambridge Conservation Initiative Collaborative Fund and Arcadia.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1111/conl.1215

    Assessing the cost of global biodiversity and conservation knowledge

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    Knowledge products comprise assessments of authoritative information supported by standards, governance, quality control, data, tools, and capacity building mechanisms. Considerable resources are dedicated to developing and maintaining knowledge products for biodiversity conservation, and they are widely used to inform policy and advise decision makers and practitioners. However, the financial cost of delivering this information is largely undocumented. We evaluated the costs and funding sources for developing and maintaining four global biodiversity and conservation knowledge products: The IUCN Red List of Threatened Species, the IUCN Red List of Ecosystems, Protected Planet, and the World Database of Key Biodiversity Areas. These are secondary data sets, built on primary data collected by extensive networks of expert contributors worldwide. We estimate that US160million(range:US160 million (range: US116-204 million), plus 293 person-years of volunteer time (range: 278-308 person-years) valued at US14million(rangeUS 14 million (range US12-16 million), were invested in these four knowledge products between 1979 and 2013. More than half of this financing was provided through philanthropy, and nearly three-quarters was spent on personnel costs. The estimated annual cost of maintaining data and platforms for three of these knowledge products (excluding the IUCN Red List of Ecosystems for which annual costs were not possible to estimate for 2013 ) is US6.5millionintotal(range:US6.5 million in total (range: US6.2-6.7 million). We estimated that an additional US114millionwillbeneededtoreachpredefinedbaselinesofdatacoverageforallthefourknowledgeproducts,andthatonceachieved,annualmaintenancecostswillbeapproximatelyUS114 million will be needed to reach pre-defined baselines of data coverage for all the four knowledge products, and that once achieved, annual maintenance costs will be approximately US12 million. These costs are much lower than those to maintain many other, similarly important, global knowledge products. Ensuring that biodiversity and conservation knowledge products are sufficiently up to date, comprehensive and accurate is fundamental to inform decision-making for biodiversity conservation and sustainable development. Thus, the development and implementation of plans for sustainable long-term financing for them is critical

    Identifying species likely threatened by international trade on the IUCN Red List can inform CITES trade measures

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    Overexploitation is a major threat to biodiversity and international trade in many species is regulated through the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). However, there is no established method to systematically determine which species are most at risk from international trade to inform potential trade measures under CITES. Here, we develop a mechanism using the International Union for Conservation of Nature’s Red List of Threatened Species to identify species that are likely to be threatened by international trade. Of 2,211 such species, CITES includes 59% (1,307 species), leaving two-fifths overlooked and in potential need of international trade regulation. Our results can inform deliberations on potential proposals to revise trade measures for species at CITES Conference of the Parties meetings. We also show that, for taxa with biological resource use documented as a threat, the number of species threatened by local and national use is four times greater than species likely threatened by international trade. To effectively address the overexploitation of species, interventions focused on achieving sustainability in international trade need to be complemented by commensurate measures to ensure that local and national use and trade of wildlife is well-regulated and sustainable

    A component model for building systems software

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    OpenCOM v2 is our experimental language-independent component-based systems-building technology. OpenCOM offers more than merely a component-based programming model. First, it is a runtime component model and supports dynamic runtime reconfiguration of systems (i.e. one can load, unload, bind, and rebind components at runtime). Second, it explicitly supports the deployment of the model in a wide range of `deployment environments' (e.g. operating systems, PDAs, embedded devices, network processors). Third, it allows the particularities of different deployment environments to be selectively hidden from/ made visible to the OpenCOM programmer without inherent performance overhead

    Reflective middleware-based programmable networking

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    In the past few years significant progress has been made in the design and implementation of reflective middleware platforms—i.e., platforms that, through reflection, can be flexibly configured, and run-time adapted/ reconfigured, especially in terms of non-functional properties like timeliness, resourcing, transactional behaviour, and security. Recently, we have initiated a project that investigates applying our previous reflective middleware work to the demanding and novel—for reflective middleware—area of programmable networking environments. In general, these environments offer the capability to inject code into network nodes so that their forwarding behaviour can be tailored on behalf of individual organisations, applications, or users. The fact that programmable networking software operates in a complex, Multilanguage and OS, environment and has strong requirements for dynamic deployment, 24x7 operation, managed software evolution, high performance, QoS/ resource management, adaptivity and security, makes it an ideal testing ground for the reflective middleware approach [Schmid,02]. In this position paper we outline salient characteristics of programmable networking environments and discuss how our particular reflective middleware approach, which employs a component-based architecture as one of its central tenets, offers the potential for more deployable, more flexible, and more evolvable programmable networking infrastructures. The remainder of the paper is structured as follows. First, §2 briefly surveys our previous work on reflective middleware, and §3 briefly characterises programmable networking environments. Next, §4 outlines our approach, and §5 discusses our progress to date. Finally, §6 analyses related work (in programmable networking, in component-based systems, and in reflective middleware), and §7 presents our conclusions and indicates areas of planned future work

    A re-configurable component model for programmable nodes

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    Recently developed networked services have been demanding architectures that accommodate an increasingly diverse range of applications requirements (e.g. mobility, multicast, QoS), as well as system requirements (e.g. specialized processing hardware). This is particularly crucial for architectures of network systems where the lack of extensibility and interoperability has been a constant struggle, hindering the provision of novel services. It is also clear that to achieve such flexibility these systems must support extensibility and re-configurability of the base functionality subsequent to the initial deployment. In this paper we present a component model that addresses these concerns. We also discuss the application of the component model in network processor-based programmable networking environments and discuss how our approach can offer a more deployable, flexible and extensible networking infrastructure

    Enabling re-configurability on component-based programmable nodes

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    Recently developed net worked services have been demanding architectures that accommodate an increasingly diverse range of applications requirements (e.g. mobility, multicast, QoS), as well as system requirements (e.g. exploiting specialized processing hardware). This is particularly crucial for architectures of network systems where the lack of extensibility and interoperability has been a constant struggle, hindering the Provision of novel services. It is also clear that to achieve such flexibility these systems must support extensibility and re-configurability of the base functionality subsequent to the initial deployment. Based on our experience with middleware platforms, we argue that re-configurability of network services is best implemented by means of reflection. In this position paper we present component-based approach to developing flexible networked systems, especially targeted at the Intel IXP 1200 programmable networking environment and discuss how our approach can offer a more deployable, flexible and extensible networking infrastructure. We show the viability of our component model to re-configure services on the Intel 1XP1200 platform. An application scenario is presented to validate our approach to enable re-configuration of’ services across different layers of an IXP1200-based router platform

    Managing dynamic reconfiguration in component-based systems

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    We propose a meta-framework called 'Plastik' which i) supports the specification and creation of runtime component-framework-based software systems and ii) facilitates and manages the runtime reconfiguration of such systems while ensuring integrity across changes. The meta-framework is fundamentally an integration of an architecture description language (an extension of ACME/Armani) and a reflective component runtime (OpenCOM). Plastik-generated component frameworks can be dynamically reconfigured either through programmed changes (which are foreseen at design time and specified at the ADL level); or through ad-hoc changes (which are unforeseen at design time but which are nevertheless constrained by invariants specified at the ADL level). We provide in the paper a case study that illustrates the operation and benefits of Plastik
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