Decrypting Video Quality from Encrypted Streaming Traffic

International audienc

Statistical analysis of network traffic for anomaly detection and quality of service provisioning

Network-wide traffic analysis and monitoring in large-scale networks is a challenging and expensive task. In this thesis work we have proposed to analyze the traffic of a large-scale IP network from aggregated traffic measurements, reducing measurement overheads and simplifying implementation issues. We have provided contributions in three different networking fields related to network-wide traffic analysis and monitoring in large-scale IP networks. The first contribution regards Traffic Matrix (TM) modeling and estimation, where we have proposed new statistical models and new estimation methods to analyze the Origin-Destination (OD) flows of a large-scale TM from easily available link traffic measurements. The second contribution regards the detection and localization of volume anomalies in the TM, where we have introduced novel methods with solid optimality properties that outperform current well-known techniques for network-wide anomaly detection proposed so far in the literature. The last contribution regards the optimization of the routing configuration in large-scale IP networks, particularly when the traffic is highly variable and difficult to predict. Using the notions of Robust Routing Optimization we have proposed new approaches for Quality of Service provisioning under highly variable and uncertain traffic scenarios. In order to provide strong evidence on the relevance of our contributions, all the methods proposed in this thesis work were validated using real traffic data from different operational networks. Additionally, their performance was compared against well-known works in each field, showing outperforming results in most cases. Taking together the ensemble of developed TM models, the optimal network-wide anomaly detection and localization methods, and the routing optimization algorithms, this thesis work offers a complete solution for network operators to efficiently monitor large-scale IP networks from aggregated traffic measurements and to provide accurate QoS-based performance, even in the event of volume traffic anomalie

El toque femenino en la literatura de cordel. Análisis del papel de las mujeres y de las representaciones sobre ellas en la prensa popular española de los siglos XVIII y XIX

La presente comunicación pretende destacar el activo papel de las mujeres en el desarrollo de la prensa popular de los siglos XVIII y XIX, y a su vez examinar las imágenes de las españolas en dicha prensa mediante el análisis de estos impresos pre-periodísticos. De esta manera, aspiramos a contribuir a la reconstrucción de la Historia de las mujeres, utilizando como corpus documental una selección de casi 300 romances vulgares, conservados en el Fondo Hazañas de la Biblioteca de Humanidades de la Universidad de Sevilla. Aunque en muchos de los impresos analizados la desigualdad de género y el discurso machista están presentes, también aparecen otros argumentos que anuncian la paulatina mejora de la situación de las mujeres españolas a lo largo del tiempo. Entre los apuntes más reveladores de esta investigación se encuentra el hallazgo de relatos sobre heroínas atrevidas y díscolas, que trasgreden el estereotipo clásico de la muchacha sumisa e inocente. Este hecho pone de manifiesto el valor de estas historias, que aún siendo en su mayoría pura ficción, quizás inspiraran a sus lectoras a realizar acciones excepcionales en la vida real, o incluso, podrían suponer el germen de las posteriores proclamas feministas. Por tanto, proponemos echar la vista atrás con una nueva mirada, libre de prejuicios, y reescribir la historia desde una necesaria perspectiva con enfoque de género

Labeling Methods for Partially Ordered Paths

The landscape of applications and subroutines relying on shortest path computations continues to grow steadily. This growth is driven by the undeniable success of shortest path algorithms in theory and practice. It also introduces new challenges as the models and assessing the optimality of paths become more complicated. Hence, multiple recent publications in the field adapt existing labeling methods in an ad-hoc fashion to their specific problem variant without considering the underlying general structure: they always deal with multi-criteria scenarios and those criteria define different partial orders on the paths. In this paper, we introduce the partial order shortest path problem (POSP), a generalization of the multi-objective shortest path problem (MOSP) and in turn also of the classical shortest path problem. POSP captures the particular structure of many shortest path applications as special cases. In this generality, we study optimality conditions or the lack of them, depending on the objective functions' properties. Our final contribution is a big lookup table summarizing our findings and providing the reader an easy way to choose among the most recent multicriteria shortest path algorithms depending on their problem's weight structure. Examples range from time-dependent shortest path and bottleneck path problems to the fuzzy shortest path problem and complex financial weight functions studied in the public transportation community. Our results hold for general digraphs and therefore surpass previous generalizations that were limited to acyclic graphs

An A* Algorithm for Flight Planning Based on Idealized Vertical Profiles

The Flight Planning Problem is to find a minimum fuel trajectory between two airports in a 3D airway network under consideration of the wind. We show that this problem is NP-hard, even in its most basic version. We then present a novel A* heuristic, whose potential function is derived from an idealized vertical profile over the remaining flight distance. This potential is, under rather general assumptions, both admissible and consistent and it can be computed efficiently. The method outperforms the state-of-the-art heuristic on real-life instances

Security as a Pillar of the European Union’s Cooperation for Development in Central America

The peace-security-development nexus is present in development cooperation policies. The concept of security has changed since 9/11, consequently influencing the strategies proposed by development cooperation’s major aid donors. To study the relationship between development cooperation and security, José Antonio Sanahuja recently proposed an analytical framework for the securitization of aid, which is based on the Copenhagen School’s concept of securitization. This author argues that cooperation for development policies have shifted depending on the need to support strategies to combat terrorism. This is affecting the strategies and priorities of these policies, mainly, to struggle against poverty, and to defend the democratic component. In the Central American case, security is a priority in the European Union’s new Regional Strategy Paper for 2014-2020. In this work, we will analyze and reflect on the EU’s role in development cooperation in Central America’s security strategy. We intend to demonstrate that indeed it is not a case of securitization of aid. Despite the EU’s recent focus on security in its Central American development cooperation, it does not respond to the elements presented by Sanahuja

La sistematización de la arquitectura escolar pública : orígenes, difusión internacional y desarrollo en el Río de la Plata, 1955-1973

¿En qué consistió la Arquitectura sistemática, que llegó a tener una influencia central en la producción de viviendas y equipamientos públicos en Argentina y Uruguay durante los años sesenta y setenta? Esta tesis sostiene que la Arquitectura escolar sistemática fue la culminación de un proceso de acumulación de conocimientos y experiencias en planificación, proyecto, técnicas y organización del trabajo en oficinas públicas. Fue un proceso que se originó en la prefabricación de componentes constructivos y que luego continuó sistematizando las herramientas de proyecto y todo el ciclo de producción de arquitectura. ¿Para qué? Para lograr una arquitectura más objetiva y económica, masiva y democrática, a la que pudieran acceder (y cambiar!) todos. ¿Cómo? Modulando y estandarizando los proyectos, apuntando a industrializar la construcción definiendo una metodología de trabajo cercana al diseño industrial: investigación y desarrollo de sistemas constructivos, construcción de prototipos, ejecución masiva y evaluación para retroalimentar el siguiente ciclo.Además, la Arquitectura sistemática cuestionó convenciones disciplinares de larga tradición: la producción arquitectónica se vio desplazada de obras singulares a programas masivos, se dejó de diseñar composiciones cerradas para proyectar sistemas abiertos y flexibles, y se pasó del arquitecto como genio o artista al equipo de funcionarios comprometidos que buscaban un planteo más objetivo de los problemas y sus soluciones