DDoS Attacks with Randomized Traffic Innovation: Botnet Identification Challenges and Strategies

Distributed Denial-of-Service (DDoS) attacks are usually launched through the $botnet$, an "army" of compromised nodes hidden in the network. Inferential tools for DDoS mitigation should accordingly enable an early and reliable discrimination of the normal users from the compromised ones. Unfortunately, the recent emergence of attacks performed at the application layer has multiplied the number of possibilities that a botnet can exploit to conceal its malicious activities. New challenges arise, which cannot be addressed by simply borrowing the tools that have been successfully applied so far to earlier DDoS paradigms. In this work, we offer basically three contributions: $i)$ we introduce an abstract model for the aforementioned class of attacks, where the botnet emulates normal traffic by continually learning admissible patterns from the environment; $ii)$ we devise an inference algorithm that is shown to provide a consistent (i.e., converging to the true solution as time progresses) estimate of the botnet possibly hidden in the network; and $iii)$ we verify the validity of the proposed inferential strategy over $real$ network traces.Comment: Submitted for publicatio

Voix des peuples et idée de nation chez Herder

L'idée de nation se manifeste dans le contexte de la pensée herderienne du langage, en polémique avec les idéaux cosmopolites du siècle des Lumières. En niant une nature humaine toujours égale et sans différences qualitatives, Herder soutient l'originalité de chaque moment du développement historique, compte tenu de la nature linguistique, et donc historique, de l'homme. En utilisant une métaphore suggérée par Herder, l'humanité est un concert polyphonique, d'autant plus majestueux et harmonique que son orchestration est riche et nombreuse. Écouter la voix des peuples pour comprendre l'homme dans son expression la plus étendue: ceci est l'objectif des recherches linguistiques et historico-littéraires du jeune Herder aboutissant dans l'imposant tableau historique de Auch eine Philosophie der Geschichte. Cette vision de l'histoire, qui tend à mettre en valeur le fragment et les parties, ne conduit pas toutefois au relativisme historique, à la négation du sens universel de l'histoire, mais vise à critiquer un modèle de cosmopolitisme à la Voltaire, froid et abstrait, qui ne sait comprendre et aimer que soi-même, ayant glorifié à tel point le principe de sa propre culture qu'il reste indifférent à toutes les autres manifestations de la vie des peuples. Il en ressort, d'un côté, une vive appréciation pour l'âme de chaque peuple, âme qui par la magie du langage vit dans ses expressions les plus authentiques dans la poésie, dans les mythes et dans la religion, et, d'autre part, la primauté attribuée à ces facteurs spirituels de la vie des peuples par rapport à l'organisation politique de l'état. L'idée de nation pour Herder ne se résout donc pas dans la négation du cosmopolitisme, mais plutôt dans le refus de ce cosmopolitisme basé sur la politique, propre du siècle des Lumières, qui avait fait de la création de l'État-machine un modèle que l'on aurait voulu imposer à tous les peuples de la terre

Conserved role of Ras-GEFs in promoting aging: from yeast to mice

Commentar

Crowd-sensing our Smart Cities: a Platform for Noise Monitoring and Acoustic Urban Planning

Environmental pollution and the corresponding control measurements put in place to tackle it play a significant role in determining the actual quality of life in modern cities. Amongst the several pollutant that have to be faced on a daily basis, urban noise represent one of the most widely known for its already ascertained health-related issues. However, no systematic noise management and control activities are performed in the majority of European cities due to a series of limiting factors (e.g., expensive monitoring equipment, few available technician, scarce awareness of the problem in city managers). The recent advances in the Smart City model, which is being progressively adopted in many cities, nowadays offer multiple possibilities to improve the effectiveness in this area. The Mobile Crowd Sensing paradigm allows collecting data streams from smartphone built-in sensors on large geographical scales at no cost and without involving expert data captors, provided that an adequate IT infrastructure has been implemented to manage properly the gathered measurements. In this paper, we present an improved version of a MCS-based platform, named City Soundscape, which allows exploiting any Android-based device as a portable acoustic monitoring station and that offers city managers an effective and straightforward tool for planning Noise Reduction Interventions (NRIs) within their cities. The platform also now offers a new logical microservices architecture

Voix des peuples et idée de nation chez Herder

L'idée de nation se manifeste dans le contexte de la pensée herderienne du langage, en polémique avec les idéaux cosmopolites du siècle des Lumières. En niant une nature humaine toujours égale et sans différences qualitatives, Herder soutient l'originalité de chaque moment du développement historique, compte tenu de la nature linguistique, et donc historique, de l'homme. En utilisant une métaphore suggérée par Herder, l'humanité est un concert polyphonique, d'autant plus majestueux et harmonique que son orchestration est riche et nombreuse. Écouter la voix des peuples pour comprendre l'homme dans son expression la plus étendue: ceci est l'objectif des recherches linguistiques et historico-littéraires du jeune Herder aboutissant dans l'imposant tableau historique de Auch eine Philosophie der Geschichte. Cette vision de l'histoire, qui tend à mettre en valeur le fragment et les parties, ne conduit pas toutefois au relativisme historique, à la négation du sens universel de l'histoire, mais vise à critiquer un modèle de cosmopolitisme à la Voltaire, froid et abstrait, qui ne sait comprendre et aimer que soi-même, ayant glorifié à tel point le principe de sa propre culture qu'il reste indifférent à toutes les autres manifestations de la vie des peuples. Il en ressort, d'un côté, une vive appréciation pour l'âme de chaque peuple, âme qui par la magie du langage vit dans ses expressions les plus authentiques dans la poésie, dans les mythes et dans la religion, et, d'autre part, la primauté attribuée à ces facteurs spirituels de la vie des peuples par rapport à l'organisation politique de l'état. L'idée de nation pour Herder ne se résout donc pas dans la négation du cosmopolitisme, mais plutôt dans le refus de ce cosmopolitisme basé sur la politique, propre du siècle des Lumières, qui avait fait de la création de l'État-machine un modèle que l'on aurait voulu imposer à tous les peuples de la terre.</p

Vestibular schwannoma and ipsilateral endolymphatic hydrops: an unusual association

Vestibular schwannoma and endolymphatic hydrops are two conditions that may present with similar audio-vestibular symptoms. The association of the two in the same patient represents an unusual nding that may lead clinicians to errors and delays in diagnosis and clinical management of affected subjects. We discuss the case of a patient with an intrameatal vestibular schwannoma reporting symptoms suggestive for ipsilateral endolymphatic hydrops. The patient presented with uctuating hearing loss, tinnitus, and acute rotatory vertigo episodes, and underwent a full audiological evaluation and imaging of the brain with contrast-enhanced Magnetic Resonance Imaging. Clinical audio-vestibular and radiological examination con rmed the presence of coexisting vestibular schwannoma and endolymphatic hydrops. Hydrops was treated pharmacologically; vestibular schwannoma was monitored over time with a wait and scan protocol through conventional MRI. The association of vestibular schwannoma and endolymphatic hydrops is rare, but represents a possible nding in clinical practice. It is therefore recommended investigating the presence of inner ear disorders in patients with vestibular schwannoma and, similarly, to exclude the presence of this condition in patients with symptoms typical of inner ear disorders

An Overview of B-1 Cells as Antigen-Presenting Cells

The role of B cells as antigen-presenting cells (APCs) has been extensively studied, mainly in relation to the activation of memory T cells. Considering the B cell subtypes, the role of B-1 cells as APCs is beginning to be explored. Initially, it was described that B-1 cells are activated preferentially by T-independent antigens. However, some reports demonstrated that these cells are also involved in a T-dependent response. The aim of this review is to summarize information about the ability of B-1 cells to play a role as APCs and to briefly discuss the role of the BCR and toll-like receptor signals in this process. Furthermore, some characteristics of B-1 cells, such as natural IgM production and phagocytic ability, could interfere in the participation of these cells in the onset of an adaptive response.FAPESPUniv Fed Sao Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Sao Paulo, BrazilUniv Fed Sao Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, Sao Paulo, BrazilFAPESP: 2008/58561-0FAPESP: 2015/01986-2Web of Scienc

Nonequilibrium electron energy distribution in Au under subpicosecond laser irradiation: A kinetic study

We have performed a kinetic study of the electron dynamic relaxation inside a Au film subjected to a subpicosecond laser pulse. For this purpose, we have developed a time-dependent numerical solution of the Boltzmann equation for the electrons inside the film considering the collision integrals due to electron–electron and electron–phonon collisions and a perturbation term due to the laser pulse. Our results show that, after the pulse excitation, electron distributions are very far from equilibrium. Therefore it is not possible, especially in the first part of the temporal evolution, to describe the relaxation of the electron distribution through a two-temperature model

Grain size effect on the electrical response of SnO2 thin and thick film gas sensors

Porous nano and micro crystalline tin oxide films were deposited by RF Magnetron Sputtering and doctor blade techniques, respectively. Electrical resistance and impedance spectroscopy measurements, as a function of temperature and atmosphere, were performed in order to determine the influence of the microstructure and working conditions over the electrical response of the sensors. The conductivity of all samples increases with the temperature and decreases in oxygen, as expected for an n-type semiconducting material. The impedance plots indicated the existence of two time constants related to the grains and the grain boundaries. The Nyquist diagrams at low frequencies revealed the changes that took place in the grain boundary region, with the contribution of the grains being indicated by the formation of a second semicircle at high frequencies. The better sensing performance of the doctor bladed samples can be explained by their lower initial resistance values, bigger grain sizes and higher porosity.Fil: Savu, Raluca. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Ponce, Miguel Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Joanni, Ednan. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Bueno, Paulo Roberto. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Castro, Miriam Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Cilense, Mario. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Varela, Jose Arana. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Longo, Elson. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi