Network monitoring and performance assessment: from statistical models to neural networks

Máster en Investigación e Innovación en Tecnologías de la Información y las ComunicacionesIn the last few years, computer networks have been playing a key role in many different fields. Companies have also evolved around the internet, getting advantage of the huge capacity of diffusion. Nevertheless, this also means that computer networks and IT systems have become a critical element for the business. In case of interruption or malfunction of the systems, this could result in devastating economic impact. In this light, it is necessary to provide models to properly evaluate and characterize the computer networks. Focusing on modeling, one has many different alternatives: from classical options based on statistic to recent alternatives based on machine learning and deep learning. In this work, we want to study the different models available for each context, paying attention to the advantage and disadvantages to provide the best solution for each case. To cover the majority of the spectrum, three cases have been studied: time-unaware phenomena, where we look at the bias-variance trade-off, time-dependent phenomena, where we pay attention the trends of the time series, and text processing to process attributes obtained by DPI. For each case, several alternatives have been studied and solutions have been tested both with synthetic data and real-world data, showing the successfulness of the proposa

Aplicación de técnicas estadísticas a registros de red para el análisis de tráfico y explotación de datos

Hoy en día, las redes definidas por software y la virtualización se abren camino en los despliegues comerciales. Cada vez más, las empresas aprovechan las posibilidades de reconfiguración y escalabilidad de la computación en la nube para su negocio. En este contexto, las tareas de gestión de red evolucionan y se adaptan a tener que considerar simultáneamente el estado de muchos dispositivos hardware o virtualizados. Por tanto, la monitorización de red se tiene que adaptar a recibir esta información y ver el estado de la red en conjunto. Esto hace necesario revisar las técnicas estadísticas y los diferentes algoritmos que fundamentan la monitorización de red, de forma que sea posible explotar los registros obtenidos para analizar el tráfico. Consecuentemente, este trabajo pretende extender las técnicas y procedimientos actuales a esta situación de monitorización pasiva en varios puntos. Se propone una herramienta de análisis de tráfico de red con diversas técnicas estadísticas que, extrayendo los datos de varios puntos, es capaz de relacionarlos y extraer información de congestión o del estado de la red a través del retardo. Esta herramienta posibilita la alimentación a sistemas de detección de anomalías o la elaboración de alertas para la reconfiguración de la red, en la que no solo se proporciona la información de que hay un patrón fuera de lo común, sino además qué zona o zonas de la red monitorizada están siendo afectadas o son responsables. Para evaluar esta herramienta, se ha creado un entorno de pruebas experimental basado en redes definidas por software y virtualización. Así, se logra tener un entorno altamente reconfigurable en el que probar diversos despliegues de manera efectiva y con un coste muy reducido, ya que solo requiere un servidor para funcionar. Con estos datos obtenidos, se ha podido validar la herramienta y observar como esta cumple con los objetivos establecidos. Además, se ha mostrado la utilidad de la herramienta estudiando un caso real basado en datos procedentes de un despliegue comercial

When satellite is all you have: watching the internet from 550 ms

Satellite Communication(SatCom) offers internet connectivity where traditional infrastructures are too expensive to deploy. When using satellites in a geostationary orbit, the distance from Earth forces a round trip time higher than 550ms. Coupled with the limited and shared capacity of the physical link, this poses a challenge to the traditional internet access quality we are used to. In this paper, we present the first passive characterization of the traffic carried by an operational SatCom network. With this unique vantage point, we observe the performance of the SatCom technology, as well as the usage habits of subscribers in different countries in Europe and Africa. We highlight the implications of such technology on Internet usage and functioning, and we pinpoint technical challenges due to the CDN and DNS resolution issues, while discussing possible optimizations that the ISP could implement to improve the service offered to SatCom subscribers

Analysis of top internet websites load times

“© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, 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 component of this work in other works”Motivated by the significant surge in demand of web browsing traffic, the economic costs of minimizing delays, and the paramount importance of Web Quality of Experience (WebQoE), this paper delves into the study of website load times during user navigation. In order to answer to the premises of the study, measurements concerning the W3C timing metrics of the top Internet domains were actively and periodically obtained during a month from different geographical regions. We found that these metrics distribution is akin to the Gamma distribution with positive bias, and they vary influenced by geographical location, time, and day of the week. Finally, the popularity of these websites has been compared to their performance, showing that some actors consistently deliver the best quality while others fall behind, despite their relevance in the rankingsThis research has been partially funded by the Angolan Government, by Universidad Autonoma de Madrid, by the Spanish State Research Agency under the project AgileMon (AEI PID2019-104451RB-C21) and by the Spanish Ministry of Science, Innovation and Universities under the program for the training of university lecturers (Grant number: FPU19/05678

FlexiTop: A flexible and scalable network monitoring system for Over-The-Top services

Nowadays, the demand of Over-The-Top (OTT) services such as multimedia streaming, web services or social networking is rapidly increasing. Consequently, there is a wide interest in studying the quality of these services so that Internet Service Providers (ISP) can deliver the best experience to their clients. For this purpose, we present FlexiTop, a flexible and scalable system to actively monitor these OTT services, which allows an operator to obtain metrics with a limited resource usage. Due to the continuous evolution of OTT services, this system was designed with different approaches that can be extrapolated to future situations. By looking at the results, the proposal meets all the expectations and requirements and therefore it proves its success. The proposed design was implemented and validated with different alternatives whenever it was possible, both in wired and wireless networks. Moreover, long-time testing was performed to both ensure its stability and analyze the obtained dataThis work has been partially supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund under the project TRÁFICA (MINECO/FEDER TEC2015-69417-C2-1-R

Natural language processing for web browsing analytics: Challenges, lessons learned, and opportunities

In an Internet arena where the search engines and other digital marketing firms’ revenues peak, other actors still have open opportunities to monetize their users’ data. After the convenient anonymization, aggregation, and agreement, the set of websites users visit may result in exploitable data for ISPs. Uses cover from assessing the scope of advertising campaigns to reinforcing user fidelity among other marketing approaches, as well as security issues. However, sniffers based on HTTP, DNS, TLS or flow features do not suffice for this task. Modern websites are designed for preloading and prefetching some contents in addition to embedding banners, social networks’ links, images, and scripts from other websites. This self-triggered traffic makes it confusing to assess which websites users visited on purpose. Moreover, DNS caches prevent some queries of actively visited websites to be even sent. On this limited input, we propose to handle such domains as words and the sequences of domains as documents. This way, it is possible to identify the visited websites by translating this problem to a text classification context and applying the most promising techniques of the natural language processing and neural networks fields. After applying different representation methods such as TF–IDF, Word2vec, Doc2vec, and custom neural networks in diverse scenarios and with several datasets, we can state websites visited on purpose with accuracy figures over 90%, with peaks close to 100%, being processes that are fully automated and free of any human parametrizationThis research has been partially funded by the Spanish State Research Agency under the project AgileMon (AEI PID2019-104451RBC21) and by the Spanish Ministry of Science, Innovation and Universities under the program for the training of university lecturers (Grant number: FPU19/05678

Black list and Alert list of the Aquatic Invasive Alien Species in the Iberian Peninsula: an action of the LIFE INVASAQUA

Resumen del trabajo presentado en VI Congreso Nacional sobre Especies Exóticas Invasoras y I Congreso Ibérico sobre EEI (EEI 2022) celebrado en Navarra del 20 al 23 de abril de 2022.One of the objectives of LIFE INVASQUA project is to develop tools that will be more efficient the Early Warning and Rapid Response (EWRR) framework for Invasive Alien Species in the Iberian Peninsula. Horizon scanning for high-risk IAS is basic in implementing measures to reduce new invasions, developing Alert lists, and to focus effort in the species already established, for instance making a Black list. We developed a trans national horizon scanning exercise focused on inland waters of Spain and Portugal in order to provide a prioritized lists (Black list and Alert list) of aquatic IAS that may pose a threat to aquatic ecosystems and socio economic sectors in the future. We followed a step approach of existing information about IAS (Plants, Freshwater Invertebrates, Estuarine Invertebrates and Vertebrates; 127 established taxa in Black list; 90 non established taxa in Alert list) combining with an expert scoring of prioritized taxa. IAS established in the Iberian aquatic system consistently highlighted as the worst included vertebrates (e.g. Cyprinus carpio, Gambusia holbrooki, Silurus glanis), freshwater and estuarine invertebrates (e.g. Procambarus clarkii, Dreissena polymorpha, Pacifastacus leniusculus, Ficopomatus enigmaticus, Callinectes sapidus, Corbicula fluminea) and plants (e.g. Eichhornia crassipes, Azolla filiculoides, Ludwigia grandiflora). Amongst taxa not yet established (Alert list), expert pointed to Perna viridis, Hydroides dirampha, Dreissena bugensis, Procambarus fallax f. virginallis, Perccottus glenii with higher risk of invasion, ecological and socioeconomic impacts. Over 20.6% of the taxa in the preliminary black list received no votes (no prioritization) by experts, 17.8% in the innitial alert list. Our horizon scanning approach is inclusive of all-taxa, prioritizes both established and emerging biological threats across trans-national scales, and considers not only the ecological impact, but also potential direct economic consequences as well as the manageability of invasive species.This work received funds from the LIFE Programme (LIFE17 GIE/ES/000515)

Smart modeling techniques for network and service management

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Escuela Politécnica Superior, Departamento de Tecnología Electrónica y de las Comunicaciones. Fecha de Lectura: 07-06-2023It was partially funded under the projects AgileMon (AEI PID2019-104451RB-C21) of the Spanish State Research Agency (DOI: 10.13039/501100011033) and H2020 METRO-HAUL (Project ID: 761727) of the European Commission (DOI: 10.13039/501100000780

Motor Alternatiu d'aportació de calor externa emprant blocs motor de MACI de forma independent com a compressor i expansor

El treball realitzat en aquest projecte consisteix en la creació d’una eina informàtica d’ajuda per aquells qui es disposin a dimensionar un tipus concret de generadors d’energia; així com en l’exposició detallada de les premisses, variables, constants i equivalències usades, de cara una bona comprensió i utilització de la mateixa, com també per facilitar-ne la utilització en altres projectes. Els generadors als quals s’ha encarat l’elaboració d’aquest projecte són màquines tèrmiques d’aportació de calor externa, on les funcions de compressor i expansor siguin exercides per dos motors MACI (Motor Alternatiu de Combustió Interna) de cilindrades no necessàriament iguals, i on el fluid que realitzi el cicle termodinàmic sigui l’aire captat a temperatura i pressió ambientals. La finalitat del programa és simular el cicle termodinàmic i calcular resultats teòrics de funcionament dels generadors que es desitgin estudiar, per a les diferents configuracions de dimensionament dels components. El programa ha estat desenvolupat en Matlab® i es presenta en format executable per entorn Windows®