136 research outputs found

    STCP: A New Transport Protocol for High-Speed Networks

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    Transmission Control Protocol (TCP) is the dominant transport protocol today and likely to be adopted in future high‐speed and optical networks. A number of literature works have been done to modify or tune the Additive Increase Multiplicative Decrease (AIMD) principle in TCP to enhance the network performance. In this work, to efficiently take advantage of the available high bandwidth from the high‐speed and optical infrastructures, we propose a Stratified TCP (STCP) employing parallel virtual transmission layers in high‐speed networks. In this technique, the AIMD principle of TCP is modified to make more aggressive and efficient probing of the available link bandwidth, which in turn increases the performance. Simulation results show that STCP offers a considerable improvement in performance when compared with other TCP variants such as the conventional TCP protocol and Layered TCP (LTCP)

    D3.2 Cost Concept Model and Gateway Specification

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    This document introduces a Framework supporting the implementation of a cost concept model against which current and future cost models for curating digital assets can be benchmarked. The value built into this cost concept model leverages the comprehensive engagement by the 4C project with various user communities and builds upon our understanding of the requirements, drivers, obstacles and objectives that various stakeholder groups have relating to digital curation. Ultimately, this concept model should provide a critical input to the development and refinement of cost models as well as helping to ensure that the curation and preservation solutions and services that will inevitably arise from the commercial sector as ‘supply’ respond to a much better understood ‘demand’ for cost-effective and relevant tools. To meet acknowledged gaps in current provision, a nested model of curation which addresses both costs and benefits is provided. The goal of this task was not to create a single, functionally implementable cost modelling application; but rather to design a model based on common concepts and to develop a generic gateway specification that can be used by future model developers, service and solution providers, and by researchers in follow-up research and development projects.<p></p> The Framework includes:<p></p> ‱ A Cost Concept Model—which defines the core concepts that should be included in curation costs models;<p></p> ‱ An Implementation Guide—for the cost concept model that provides guidance and proposes questions that should be considered when developing new cost models and refining existing cost models;<p></p> ‱ A Gateway Specification Template—which provides standard metadata for each of the core cost concepts and is intended for use by future model developers, model users, and service and solution providers to promote interoperability;<p></p> ‱ A Nested Model for Digital Curation—that visualises the core concepts, demonstrates how they interact and places them into context visually by linking them to A Cost and Benefit Model for Curation.<p></p> This Framework provides guidance for data collection and associated calculations in an operational context but will also provide a critical foundation for more strategic thinking around curation such as the Economic Sustainability Reference Model (ESRM).<p></p> Where appropriate, definitions of terms are provided, recommendations are made, and examples from existing models are used to illustrate the principles of the framework

    FLAD: Adaptive Federated Learning for DDoS Attack Detection

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    Federated Learning (FL) has been recently receiving increasing consideration from the cybersecurity community as a way to collaboratively train deep learning models with distributed profiles of cyberthreats, with no disclosure of training data. Nevertheless, the adoption of FL in cybersecurity is still in its infancy, and a range of practical aspects have not been properly addressed yet. Indeed, the Federated Averaging algorithm at the core of the FL concept requires the availability of test data to control the FL process. Although this might be feasible in some domains, test network traffic of newly discovered attacks cannot be always shared without disclosing sensitive information. In this paper, we address the convergence of the FL process in dynamic cybersecurity scenarios, where the trained model must be frequently updated with new recent attack profiles to empower all members of the federation with latest detection features. To this aim, we propose FLAD (adaptive Federated Learning Approach to DDoS attack detection), a FL solution for cybersecurity applications based on an adaptive mechanism that orchestrates the FL process by dynamically assigning more computation to those members whose attacks profiles are harder to learn, without the need of sharing any test data to monitor the performance of the trained model. Using a recent dataset of DDoS attacks, we demonstrate that FLAD outperforms the original FL algorithm in terms of convergence time and accuracy across a range of unbalanced datasets of heterogeneous DDoS attacks. We also show the robustness of our approach in a realistic scenario, where we retrain the deep learning model multiple times to introduce the profiles of new attacks on a pre-trained model

    Beyond multimedia adaptation: Quality of experience-aware multi-sensorial media delivery

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    Multiple sensorial media (mulsemedia) combines multiple media elements which engage three or more of human senses, and as most other media content, requires support for delivery over the existing networks. This paper proposes an adaptive mulsemedia framework (ADAMS) for delivering scalable video and sensorial data to users. Unlike existing two-dimensional joint source-channel adaptation solutions for video streaming, the ADAMS framework includes three joint adaptation dimensions: video source, sensorial source, and network optimization. Using an MPEG-7 description scheme, ADAMS recommends the integration of multiple sensorial effects (i.e., haptic, olfaction, air motion, etc.) as metadata into multimedia streams. ADAMS design includes both coarse- and fine-grained adaptation modules on the server side: mulsemedia flow adaptation and packet priority scheduling. Feedback from subjective quality evaluation and network conditions is used to develop the two modules. Subjective evaluation investigated users' enjoyment levels when exposed to mulsemedia and multimedia sequences, respectively and to study users' preference levels of some sensorial effects in the context of mulsemedia sequences with video components at different quality levels. Results of the subjective study inform guidelines for an adaptive strategy that selects the optimal combination for video segments and sensorial data for a given bandwidth constraint and user requirement. User perceptual tests show how ADAMS outperforms existing multimedia delivery solutions in terms of both user perceived quality and user enjoyment during adaptive streaming of various mulsemedia content. In doing so, it highlights the case for tailored, adaptive mulsemedia delivery over traditional multimedia adaptive transport mechanisms

    An Adaptive Flow-Aware Packet Scheduling Algorithm for Multipath Tunnelling

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    This paper proposes AFMT, a packet scheduling algorithm to achieve adaptive flow-aware multipath tunnelling. AFMT has two unique properties. Firstly, it implements robust adaptive traffic splitting for the subtunnels. Secondly, it detects and schedules bursts of packets cohesively, a scheme that already enabled traffic splitting for load balancing with little to no packet reordering. Several NS-3 experiments over different network topologies show that AFMT successfully deals with changing path characteristics due to background traffic while increasing throughput and reliability.Comment: submitted and accepted on IEEE LCN 2019, 4 pages, 5 figure

    Differential chromatin binding preference is the result of the neo-functionalization of the TB1 clade of TCP transcription factors in grasses

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    The understanding of neo-functionalization of plant transcription factors (TFs) after gene duplication has been extensively focused on changes in protein–protein interactions, the expression pattern of TFs, or the variation of cis-elements bound by TFs. Yet, the main molecular role of a TF, that is, its specific chromatin binding for the direct regulation of target gene expression, continues to be mostly overlooked. Here, we studied the TB1 clade of the TEOSINTE BRANCHED 1, CYCLOIDEA, PROLIFERATING CELL FACTORS (TCP) TF family within the grasses (Poaceae). We identified an Asp/Gly amino acid replacement within the TCP domain, originated within a paralog TIG1 clade exclusive for grasses. The heterologous expression of Zea mays TB1 and its two paralogs BAD1 and TIG1 in Arabidopsis mutant plants lacking the TB1 ortholog BRC1 revealed distinct functions in plant development. Notably, the Gly acquired in the TIG1 clade does not impair TF homodimerization and heterodimerization, while it modulates chromatin binding preferences. We found that in vivo TF recognition of target promoters depends on this Asp/Gly mutation and directly impacts downstream gene expression and subsequent plant development. These results provided new insights into how natural selection fine-tunes gene expression regulation after duplication of TFs to define plant architecture.Fil: Mansilla, Natanael. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto de AgrobiotecnologĂ­a del Litoral. Universidad Nacional del Litoral. Instituto de AgrobiotecnologĂ­a del Litoral; ArgentinaFil: Fonouni-farde, Camille Audrey. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto de AgrobiotecnologĂ­a del Litoral. Universidad Nacional del Litoral. Instituto de AgrobiotecnologĂ­a del Litoral; ArgentinaFil: Ariel, Federico Damian. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto de AgrobiotecnologĂ­a del Litoral. Universidad Nacional del Litoral. Instituto de AgrobiotecnologĂ­a del Litoral; ArgentinaFil: Lucero, Leandro Exequiel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto de AgrobiotecnologĂ­a del Litoral. Universidad Nacional del Litoral. Instituto de AgrobiotecnologĂ­a del Litoral; Argentin

    Digital Image Steganography

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    Steganography is defined as the science of hiding or embedding data in a transmission medium. Its ultimate objectives, which are undetectability, robustness (i.e., against image processing and other attacks) and capacity of the hidden data (i.e., how much data we can hide in the carrier file), are the main factors that distinguish it from other sisters-in science. techniques, namely watermarking and Cryptography. This paper provides an overview of well known Steganography methods. It identifies current research problems in this area and discusses how our current research approach could solve some of these problems. We propose using human skin tone detection in colour images to form an adaptive context for an edge operator which will provide an excellent secure location for data hiding

    Model Organisms in Plant Genetics

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    Model plants are required for research when targeted plant species are difficult to study or when research material is unavailable. Importantly, knowledge gained from model plants can be generally translated to other related plant species because many key cellular and molecular processes are conserved and regulated by ‘blueprint’ genes inherited from a common ancestor. Model Organisms in Plant Genetics addresses characteristics of model plants such as Arabidopsis, moss, soybean, maize, and cotton, highlighting their advantages and limitations as well as their importance in studies of plant development, plant genome polyploidization, adaptive selection, evolution, and domestication, as well as their importance in crop improvement

    PIPeR: Impact of power-awareness on social-based opportunistic advertising

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    Interest and social-awareness can be valuable determinants in decisions related to content delivery in mobile environments. Under certain conditions, we can deliver content with less cost and better delivery ratios, while only involving users that are interested in the type of content being delivered. However, the depletion of valuable power resources poses a deterrent to node participation in such interest-aware forwarding systems. No significant research contribution has been identified to collectively maximize the benefits of social, interest, and power awareness. In this work, we propose a new algorithm called PIPeR which integrates power awareness with an interest and socially aware forwarding algorithm called IPeR. Through simulations, we present and evaluate four modes of PIPeR. The results show that PIPeR is more fair and preserves at least 22% of the power IPeR consumes with less delay, while relying significantly on interested forwarders and with comparable cost to maintain similar delivery ratios
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