26 research outputs found

    LIFT: a Local IPSec-aware Freezing Protocol to improve TCP Performance in Satellite Networks

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    In this paper a protocol, local to the satellite link, is defined in order to boost TCP performance in mobile integrated wired-satellite Internet. It has been conceived to help to overcome the well known retransmissions competition problem that arises when a satellite reliable link layer protocol is used to face satellite link errors. This protocol, called Local IPSec-aware Freezing proTocol (LIFT), has been designed to allow the satellite gateway, even in the presence of communications secured by IPSec, to freeze the TCP sender when it perceives a possible delay due to satellite channel conditions. The effectiveness of LIFT has been evaluated, using the ns-2 tool, in terms of Web page download mean time for a satellite mobile host. Simulation results have shown that the adoption of LIFT protocol provides substantial improvements in TCP performance

    An algorithm for controlling packet size in IEEE 802.16e networks

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    This paper proposes an algorithm to be used in IEEE 802.16e networks for adapting MAC PDU size to wireless channel behavior when ARQ is adopted at MAC layer. The algorithm is based on an analytical approach for dynamically evaluating the optimal packet size. The latter is derived from an expression of the ARQ protocol efficiency, obtained by exploiting a finite-state Markov error model which also takes into account Adaptive Modulation/Coding. The effectiveness of the designed algorithm in improving TCP performance has been evaluated

    A multi-service data management platform for scientific oceanographic products

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    Abstract. An efficient, secure and interoperable data platform solution has been developed in the TESSA project to provide fast navigation and access to the data stored in the data archive, as well as a standard-based metadata management support. The platform mainly targets scientific users and the situational sea awareness high-level services such as the decision support systems (DSS). These datasets are accessible through the following three main components: the Data Access Service (DAS), the Metadata Service and the Complex Data Analysis Module (CDAM). The DAS allows access to data stored in the archive by providing interfaces for different protocols and services for downloading, variables selection, data subsetting or map generation. Metadata Service is the heart of the information system of the TESSA products and completes the overall infrastructure for data and metadata management. This component enables data search and discovery and addresses interoperability by exploiting widely adopted standards for geospatial data. Finally, the CDAM represents the back-end of the TESSA DSS by performing on-demand complex data analysis tasks

    Big Data Analytics on Large-Scale Scientific Datasets in the INDIGO-DataCloud Project

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    In the context of the EU H2020 INDIGO-DataCloud project several use case on large scale scientfic data analysis regarding different research communities have been implemented. All of them require the availability of large amount of data related to either output of imulations or observed data from sensors and need scientic (big) data solutions to run data analysis experiments. More specically,the paper presents the case studies related to the following research communities: (i) the European Multidisciplinary Seaoor and water column Observatory (INGV-EMSO), (ii) the Large Binocular Tele-scope, (iii) LifeWatch, and (iv) the European Network for Earth System Modelling (ENES).EGI Foundation, IBM ResearchPublishedUniversity of Siena, Palazzo del Rettorato, Banchi di Sotto, 55, 53100 Siena (SI), Italy1VV. Altr

    An Integrated Big and Fast Data Analytics Platform for Smart Urban Transportation Management

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    (c) 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.[EN] Smart urban transportation management can be considered as a multifaceted big data challenge. It strongly relies on the information collected into multiple, widespread, and heterogeneous data sources as well as on the ability to extract actionable insights from them. Besides data, full stack (from platform to services and applications) Information and Communications Technology (ICT) solutions need to be specifically adopted to address smart cities challenges. Smart urban transportation management is one of the key use cases addressed in the context of the EUBra-BIGSEA (Europe-Brazil Collaboration of Big Data Scientific Research through Cloud-Centric Applications) project. This paper specifically focuses on the City Administration Dashboard, a public transport analytics application that has been developed on top of the EUBra-BIGSEA platform and used by the Municipality stakeholders of Curitiba, Brazil, to tackle urban traffic data analysis and planning challenges. The solution proposed in this paper joins together a scalable big and fast data analytics platform, a flexible and dynamic cloud infrastructure, data quality and entity matching algorithms as well as security and privacy techniques. By exploiting an interoperable programming framework based on Python Application Programming Interface (API), it allows an easy, rapid and transparent development of smart cities applications.This work was supported by the European Commission through the Cooperation Programme under EUBra-BIGSEA Horizon 2020 Grant [Este projeto e resultante da 3a Chamada Coordenada BR-UE em Tecnologias da Informacao e Comunicacao (TIC), anunciada pelo Ministerio de Ciencia, Tecnologia e Inovacao (MCTI)] under Grant 690116.Fiore, S.; Elia, D.; Pires, CE.; Mestre, DG.; Cappiello, C.; Vitali, M.; Andrade, N.... (2019). An Integrated Big and Fast Data Analytics Platform for Smart Urban Transportation Management. IEEE Access. 7:117652-117677. https://doi.org/10.1109/ACCESS.2019.2936941S117652117677

    SeaConditions: a web and mobile service for safer professional and recreational activities in the Mediterranean Sea

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    Abstract. Reliable and timely information on the environmental conditions at sea is key to the safety of professional and recreational users as well as to the optimal execution of their activities. The possibility of users obtaining environmental information in due time and with adequate accuracy in the marine and coastal environment is defined as sea situational awareness (SSA). Without adequate information on the environmental meteorological and oceanographic conditions, users have a limited capacity to respond, which has led to loss of lives and to large environmental disasters with enormous consequent damage to the economy, society and ecosystems. Within the framework of the TESSA project, new SSA services for the Mediterranean Sea have been developed. In this paper we present SeaConditions, which is a web and mobile application for the provision of meteorological and oceanographic observation and forecasting products. Model forecasts and satellite products from operational services, such as ECMWF and CMEMS, can be visualized in SeaConditions. In addition, layers of information related to bathymetry, sea level and ocean-colour data (chl a and water transparency) are displayed. Ocean forecasts at high spatial resolutions are included in the version of SeaConditions presented here. SeaConditions provides a user-friendly experience with a fluid zoom capability, facilitating the appropriate display of data with different levels of detail. SeaConditions is a single point of access to interactive maps from different geophysical fields, providing high-quality information based on advanced oceanographic models. The SeaConditions services are available through both web and mobile applications. The web application is available at www.sea-conditions.com and is accessible and compatible with present-day browsers. Interoperability with GIS software is implemented. User feedback has been collected and taken into account in order to improve the service. The SeaConditions iOS and Android apps have been downloaded by more than 105 000 users to date (May 2016), and more than 100 000 users have visited the web version

    INDIGO-DataCloud: A data and computing platform to facilitate seamless access to e-infrastructures

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    This paper describes the achievements of the H2020 project INDIGO-DataCloud. The project has provided e-infrastructures with tools, applications and cloud framework enhancements to manage the demanding requirements of scientific communities, either locally or through enhanced interfaces. The middleware developed allows to federate hybrid resources, to easily write, port and run scientific applications to the cloud. In particular, we have extended existing PaaS (Platform as a Service) solutions, allowing public and private e-infrastructures, including those provided by EGI, EUDAT, and Helix Nebula, to integrate their existing services and make them available through AAI services compliant with GEANT interfederation policies, thus guaranteeing transparency and trust in the provisioning of such services. Our middleware facilitates the execution of applications using containers on Cloud and Grid based infrastructures, as well as on HPC clusters. Our developments are freely downloadable as open source components, and are already being integrated into many scientific applications

    La riconversione della spesa pubblica come terreno di innovazione. Soluzioni residenziali per l’emergenza abitativa a Milano

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    Mutamenti strutturali e recessione economica hanno impatti significativi sulle condizioni di vita, specie nei sistemi di welfare familisti dell’Europa del Sud comparativamente meno redistributivi e inclusivi. Tra le implicazioni più evidenti vi è una fatica crescente a mantenere l’alloggio di abitazione, l’incremento delle morosità in relazione sia agli affitti sia ai mutui, l’aumento e l’accelerazione delle procedure di sfratto. Chi perde la casa e non trova soluzioni nelle proprie reti primarie si rivolge ai servizi sociali dei Comuni. In assenza di soluzioni adeguate, questi ricorrono tipicamente a strutture ad alta intensità assistenziale (come Rsa e comunità) o a stanze d’albergo, soluzioni al tempo stesso costose e inappropriate. Per far fronte all’aumento dei bisogni nel quadro di risorse decrescenti, molti enti locali sperimentano – in ordine sparso – soluzioni innovative. Questo contributo analizza la recente sperimentazione di un programma di «Residenzialità sociale temporanea» promosso dal Comune di Milano, che, insieme a una riconversione e maggiore efficacia della spesa corrente, mira a configurare soluzioni residenziali più appropriate

    Managing decisions for smart grid using interdependency modeling

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    Critical infrastructures are vital complex systems for our lives. Electrical grids, gas pipelines, telecommunication networks and transportation roads are examples of those critical infrastructures. Furthermore, critical infrastructures are tightly interconnected one to another, and their interdependencies are more evident during adverse events, such as faults, natural disasters or cyber attacks. Making smart decisions is a hard task for operators. This paper wants to suggest a complete procedure for helping critical infrastructure operators in managing assets during adverse events. CISIApro simulator is an agentbased simulator able to evaluate the risk associated with the consequences of adverse events. The agent ability to produce resources is summarized into the concept of operative level. The output of CISIApro, related to the power infrastructure, is used as input of the unit commitment algorithm as an example of decision making algorithm. In this paper, the unit commitment includes network topology security constraints and a risk-based objective function. This process is validated by means of a reference scenario made of four interconnected infrastructures, within a regional area. Results are presented in order to understand how unit commitment can suggest different solutions based on different risk assessment

    Improved multi-criteria distribution network reconfiguration with information fusion

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    Electrical grids are no more isolated infrastructures but they provide services towards other infrastructures and meanwhile water networks, telecommunications, gas pipelines and transport systems are mandatory in order to produce and deliver electricity. The reconfiguration algorithm determines the optimal tree configuration of the grid, after overloads or permanent faults. In literature, the reconfiguration algorithm takes into account feasibility, radiality, load balancing and energy losses
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