Attacker Behavior-Based Metric for Security Monitoring Applied to Darknet Analysis

International audienceNetwork traffic monitoring is primordial for network operations and management for many purposes such as Quality-of-Service or security. One major difficulty when dealing with network traffic data (packets, flows...) is the poor semantic of individual attributes (number of bytes, packets, IP addresses, protocol, TCP/UDP port number...). Many attributes can be represented as numerical values but cannot be mapped to a meaningful metric space. Most notably are application port numbers. They are numerical but comparing them as integers is meaningless. In this paper, we propose a fine grained attacker behavior-based network port similarity metric allowing traffic analysis to take into account semantic relations between port numbers. The behavior of attackers is derived from passive observation of a Darknet or telescope, aggregated in a graph model, from which a semantic dissimilarity function is defined. We demonstrate the veracity of this function with real world network data in order to pro-actively block 99% of TCP scans

Adversarial Attacks on Linear Contextual Bandits

Contextual bandit algorithms are applied in a wide range of domains, from advertising to recommender systems, from clinical trials to education. In many of these domains, malicious agents may have incentives to attack the bandit algorithm to induce it to perform a desired behavior. For instance, an unscrupulous ad publisher may try to increase their own revenue at the expense of the advertisers; a seller may want to increase the exposure of their products, or thwart a competitor's advertising campaign. In this paper, we study several attack scenarios and show that a malicious agent can force a linear contextual bandit algorithm to pull any desired arm $T - o(T)$ times over a horizon of $T$ steps, while applying adversarial modifications to either rewards or contexts that only grow logarithmically as $O(\log T)$. We also investigate the case when a malicious agent is interested in affecting the behavior of the bandit algorithm in a single context (e.g., a specific user). We first provide sufficient conditions for the feasibility of the attack and we then propose an efficient algorithm to perform the attack. We validate our theoretical results on experiments performed on both synthetic and real-world datasets

port2dist: Semantic Port Distances for Network Analytics

International audienceTraffic analysis is a predominant task to support multiple types of management operations. When shifting from manually built signatures to machine learning techniques, a problem resides in the model to represent traffic features. The most notable examples are the TCP and UDP ports, near port numbers in the numerical space is not representative of a close semantic from an operational point of view. We have thus developed a technique to learn meaningful metrics between ports from scanning strategies followed by attackers. In this demonstration, we propose the port2dist tool, allowing to get, seek and retrieve semantic dissimilarities between port numbers

Structure of 2,5-dimethyl-1,3,4,6-tetraazacycl[3.3.3]azine, C10H9N5

Orientador: Prof. Dr. Ramón Sigifredo Cortés ParedesCoorientadora: Profª. Drª. Maria Lúcia Leite Ribeiro OkimotoTese (doutorado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Mecânica. Defesa : Curitiba, 20/02/2019Inclui referências: p. 202-219Área de concentração: ManufaturaResumo: A cor é um dos elementos mais importantes da vida humana, estando conscientes disso ou não. A cor está em tudo, desde a natureza, em todos os ambientes internos e externos, nos objetos circundantes, vestuários e, até mesmo, como forma de expressão verbal, ou seja, inimaginável a vida sem cor. No entanto, milhares de pessoas no mundo não têm acesso a esta informação. O presente trabalho refere-se ao desenvolvimento de código em relevo com o objetivo de possibilitar a identificação das cores às pessoas com deficiência visual por meio do tato. Esta abordagem científica e inovadora é composta de elementos em formato tridimensional, com dimensões mínimas, inspirado no elemento principal do Sistema Braille, o ponto. A abordagem metodológica partiu de revisão bibliográfica sobre o tema, investigação e avaliação criteriosa dos códigos de cores preexistentes e o desenvolvido de um sistema inovador, fundamentado na Teoria da Cor. Os códigos foram produzidos e experimentados em duas técnicas distintas: na técnica da Manufatura Aditiva (impressão em 3D) e na impressão em papel microcapsulado que produz relevos por meio de fusora térmica. Para a realização dos experimentos participaram 18 voluntários divididos em grupos de pessoas cegas, com baixa visão e com visão normal. Sendo nove mulheres e nove homens, com idades entre 25 a 64 anos. Os resultados da pesquisa evidenciaram que este sistema de código foi facilmente assimilado e memorizado pelos participantes com o tempo médio de 18,5 minutos para o ensino-aprendizado. A análise dos valores obtidos com o tempo médio de 14,08 segundos para o reconhecimento das cores através do código, comprovou que este sistema é eficaz e eficiente no que se propôs: o reconhecimento das cores pelo sentido do tato para promover inclusão e a acessibilidade da informação às pessoas com deficiência visual. Palavras-chave: Código de cor. Tecnologia Assistiva. Acessibilidade. Comunicação. Cegueira. Deficiência visual.Abstract: Color is one of the most important elements of human life, whether you are aware of it or not. The color is at all, from nature, in all internal and external environments, in the surrounding objects, garments and, even, as a form of verbal expression, unimaginable life without color. However, thousands of people in the world do not have access to this information. The present work refers to the development of code in relief with the objective of enabling the identification of the colors to people with visual impairment through tact. This scientific and innovative approach is composed of elements in three-dimensional format, with minimal dimensions, inspired by the main element of the Braille System, the point. The methodological approach was based on a bibliographic review of the theme, investigation and judicious evaluation of the pre-existing color codes and the development of an innovative system, grounded in the Color Theory. The codes were produced and tried in two distinct techniques: in the additive manufacturing technique (3D printing) and the microcapsulated paper printing that produces reliefs by means of thermal fuser. Eighteen volunteers were divided into groups of blind people, low vision and normal vision to perform the experiments. Nine women and nine men, aged between 25 and 64 years. The results of the research evidenced that this system of code was easily assimilated and memorized by the participants with an average time of 18,5 minutes for teaching/learning. The analysis of the values obtained with the average time of 14,08 seconds for the recognition of colors through the code, proved that this system is effective and efficient with has been proposed: the recognition of colors by the sense of touch to promote inclusion and accessibility information to visually impaired persons. Keywords: Color code. Assistive Technology. Accessibility. Communication. Blindness. Visual impairment.

Association between antithrombotic treatment and outcomes at 1-year follow-up in patients with atrial fibrillation: the EORP-AF General Long-Term Registry

In recent years, stroke prevention in patients with atrial fibrillation (AF) has radically changed, with increasing use of non-vitamin K antagonist oral anticoagulants (NOACs). Contemporary European data on AF thromboprophylaxis are needed

Neutrophil mobilization via plerixafor-mediated CXCR4 inhibition arises from lung demargination and blockade of neutrophil homing to the bone marrow

Blood neutrophil homeostasis is essential for successful host defense against invading pathogens. Circulating neutrophil counts are positively regulated by CXCR2 signaling and negatively regulated by the CXCR4-CXCL12 axis. In particular, G-CSF, a known CXCR2 signaler, and plerixafor, a CXCR4 antagonist, have both been shown to correct neutropenia in human patients. G-CSF directly induces neutrophil mobilization from the bone marrow (BM) into the blood, but the mechanisms underlying plerixafor-induced neutrophilia remain poorly defined. Using a combination of intravital multiphoton microscopy, genetically modified mice and novel in vivo homing assays, we demonstrate that G-CSF and plerixafor work through distinct mechanisms. In contrast to G-CSF, CXCR4 inhibition via plerixafor does not result in neutrophil mobilization from the BM. Instead, plerixafor augments the frequency of circulating neutrophils through their release from the marginated pool present in the lung, while simultaneously preventing neutrophil return to the BM. Our study demonstrates for the first time that drastic changes in blood neutrophils can originate from alternative reservoirs other than the BM, while implicating a role for CXCR4-CXCL12 interactions in regulating lung neutrophil margination. Collectively, our data provides valuable insights into the fundamental regulation of neutrophil homeostasis, which may lead to the development of improved treatment regimens for neutropenic patients.This research was funded by SIgN, A*STAR, Singapore. C.N.Z. Mattar and J.K.Y. Chan received salary support from the National Medical Research Council of Singapore (NMRC/TA/003/2012 and NMRC/CSA/012/2009, respectively).S

Galactic Outflows and Evolution of the Interstellar Medium

We present a model to self-consistently describe the joint evolution of starburst galaxies and the galactic wind resulting from this evolution. We combine the population synthesis code Starburst99 with a semi-analytical model of galactic outflows and a model for the distribution and abundances of chemical elements inside the outflows. Starting with a galaxy mass, formation redshift, and adopting a particular form for the star formation rate, we describe the evolution of the stellar populations in the galaxy, the evolution of the metallicity and chemical composition of the interstellar medium (ISM), the propagation of the galactic wind, and the metal-enrichment of the intergalactic medium (IGM). In this paper, we study the properties of the model, by varying the mass of the galaxy, the star formation rate, and the efficiency of star formation. Our main results are the following: (1) For a given star formation efficiency f*, a more extended period of active star formation tends to produce a galactic wind that reaches a larger extent. If f* is sufficiently large, the energy deposited by the stars completely expels the ISM. Eventually, the ISM is being replenished by mass loss from supernovae and stellar winds. (2) For galaxies with masses above 10^11 Msun, the material ejected in the IGM always falls back onto the galaxy. Hence lower-mass galaxies are the ones responsible for enriching the IGM. (3) Stellar winds play a minor role in the dynamical evolution of the galactic wind, because their energy input is small compared to supernovae. However, they contribute significantly to the chemical composition of the galactic wind. We conclude that the history of the ISM enrichment plays a determinant role in the chemical composition and extent of the galactic wind, and therefore its ability to enrich the IGM.Comment: 17 pages, 14 color figures. Accepted for publication in MNRA

GEO-6 assessment for the pan-European region

Through this assessment, the authors and the United Nations Environment Programme (UNEP) secretariat are providing an objective evaluation and analysis of the pan-European environment designed to support environmental decision-making at multiple scales. In this assessment, the judgement of experts is applied to existing knowledge to provide scientifically credible answers to policy-relevant questions. These questions include, but are not limited to the following:• What is happening to the environment in the pan-European region and why?• What are the consequences for the environment and the human population in the pan-European region?• What is being done and how effective is it?• What are the prospects for the environment in the future?• What actions could be taken to achieve a more sustainable future?<br/