Comunicaciones y ponencias de congresos DAC - AKS Biltzarretako komunikazioak eta txostenak

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Open Access
A first study on the use of interval-valued fuzzy sets with genetic tuning for classification with imbalanced data sets
(Springer, 2009) Sanz Delgado, José Antonio; Fernández, Alberto; Bustince Sola, Humberto; Herrera, Francisco; Automática y Computación; Automatika eta Konputazioa
Classification with imbalanced data-sets is one of the recent challenging problems in Data Mining. In this framework, the class dis- tribution is not uniform and the separability between the classes is often difficult. From the available techniques in the Machine Learning field, we focus on the use of Fuzzy Rule Based Classification Systems, as they provide an interpretable model for the end user by means of linguistic variables. The aim of this work is to increase the performance of fuzzy modeling by adding a higher degree of knowledge by means of the use of Interval- valued Fuzzy Sets. Furthermore, we will contextualize the Interval-valued Fuzzy Sets with a post-processing genetic tuning of the amplitude of their upper bounds in order to enhance the global behaviour of this methodology.
Open Access
Adjusting fuzzy automata for string similarity measuring
(EUSFLAT, 2001) Astrain Escola, José Javier; Villadangos Alonso, Jesús; González de Mendívil Moreno, José Ramón; Garitagoitia Padrones, José Ramón; Fariña Figueredo, Federico; Ingeniería Matemática e Informática; Matematika eta Informatika Ingeniaritza; Automática y Computación; Automatika eta Konputazioa
In this paper, we introduce a fuzzy automaton for computing the similarity between pairs of strings and a genetic method for adjusting its parameters. The fuzzy automaton models the edit operations needed to transform any string into another one. The selection of appropriate fuzzy operations and fuzzy membership values for the transitions leads to improve the system performance for a particular application.
Open Access
On fuzzy orderings of crisp and fuzzy intervals
(EUSFLAT, 2001) Fuentes González, Ramón; Burillo López, Pedro; Mayor, Gaspar; Automática y Computación; Automatika eta Konputazioa
First, fuzzy membership functions for the assertion '[x,y] is a positive interval' are proposed and characterized via non-decreasing real maps. Last, using those functions together with the intervaldifference and the notion of average index, comparison indexes between intervals and the ones between fuzzy intervals are proposed.
Open Access
About the intuitionistic fuzzy set generators
(Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 1997) Bustince Sola, Humberto; Mohedano Salillas, Victoria; Automática y Computación; Automatika eta Konputazioa
In this paper form the definition of intuitionistic fuzzy sets we analyze the intuitionistic fuzzy generators and the complementation in these sets. We start by defining the intuitionistic fuzzy generators in order to then study the particular cases for which this definition coincides with the fuzzy complementation. Afterwards we analyze the existence of equilibrium points, dual points and we present characterization theorems of intuitionistic fuzzy generators. Lastly, we study a manner of constructing intuitionistic fuzzy sets and analyse the structure of the complementary of intuitionistic fuzzy sets built.
Open Access
Mejoras en la identificación de tráfico de aplicación basado en firmas
(2008) Santolaya Bea, Néstor; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Morató Osés, Daniel; Automática y Computación; Automatika eta Konputazioa
Traffic identification has been based traditionally on transport protocol ports, associating always the same ports with the same applications. Nowadays that assumption is not true and new methods like signature identification or statistical techniques are applied. This work presents a method based on signature identification with some improvements. The use of regular expressions for typical applications has been studied deeply and its use has been improved in the aspects of percentage identification and resources consumption. On the other hand, a flows-record structure has been applied in order to classify those packets that do not verify any regular expression. Results are compared with the opensource related project L7-filter, and the improvements are presented. Finally, detailed regular expressions for analyzed applications are included in the paper, especially P2P applications.
Open Access
Internet mapping at IP level
(2009) García-Jiménez, Santiago; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa
The final objective of our research is to develop new techniques and ideas to create topology maps at IP level, representing Internet as a graph where nodes were routes. This means closer to reality.
Open Access
Collecting packet traces at high speed
(2006) Aguirre Cascallana, Gorka; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa
In order to capture packet traces at high speed using a low-cost platform, we have to optimize the networking stack of a general purpose operating system. Different techniques are compared with the final objective of avoiding packet loss. Among those techniques we will study the performance of NAPI [6] and PF-RING [9]. Depending on the final application, we should tune certain parameters accordingly. We also present the advantages of a multiprocessor platform and the problematic of storing full packets directly to hard disk.
Open Access
A popularity-aware method for discovering server IP addresses related to websites
(IEEE, 2013) Torres García, Luis Miguel; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Morató Osés, Daniel; Automática y Computación; Automatika eta Konputazioa
The complexity of web traffic has grown in the past years as websites evolve and new services are provided over the HTTP protocol. When accessing a website, multiple connections to different servers are opened and it is usually difficult to distinguish which servers are related to which sites. However, this information is useful from the perspective of security and accounting and can also help to label web traffic and use it as ground truth for traffic classification systems. In this paper we present a method to discover server IP addresses related to specific websites in a traffic trace. Our method uses NetFlow-type records which makes it scalable and impervious to encryption of packet payloads. It is, moreover, popularity-aware in the sense that it takes into consideration the differences in the number of accesses to each site in order to provide a better identification of servers. The method can be used to gather data from a group of interesting websites or, by applying it to a representative set of websites, it can label a sizeable number of connections in a packet trace.
Open Access
Traffic generator using Perlin Noise
(IEEE, 2012) Prieto Suárez, Iria; Izal Azcárate, Mikel; Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Study of high speed networks such as optical next generation burst or packet switched networks require large amounts of synthetic traffic to feed simulators. Methods to generate self-similar long range dependent traffic already exist but they usually work by generating large blocks of traffic of fixed time duration. This limits simulated time or require very high amount of data to be stored before simulation. On this work it is shown how self-similar traffic can be generated using Perlin Noise, an algorithm commonly used to generate 2D/3D noise for natural looking graphics. 1-dimension Perlin Noise can be interpreted as network traffic and used to generate long range dependent traffic for network simulation. The algorithm is compared to more classical approach Random Midpoint Displacement showing at traffic generated is similar but can be generated continuously with no fixed block size.
Open Access
Pamplona-traceroute: topology discovery and alias resolution to build router level Internet maps
(IEEE, 2013) García-Jiménez, Santiago; Magaña Lizarrondo, Eduardo; Morató Osés, Daniel; Izal Azcárate, Mikel; Automática y Computación; Automatika eta Konputazioa
An Internet topology map at the router level not only needs to discover IP addresses in Internet paths (traceroute) but also needs to identify IP addresses belonging to the same router (IP aliases). Both processes, discovery and IP alias resolution, have traditionally been independent tasks. In this paper, a new tool called Pamplona-traceroute is proposed to improve upon current results in a state of the art for Internet topology construction at the router level. Indirect probing using TTLscoped UDP packets, usually present in the discovery phases, is reused in IP alias resolution phases, providing high identification rates, especially in access routers.
Open Access
TNS research in progress
(Universidad Politécnica de Cartagena, Servicio de Documentación, 2012) Izal Azcárate, Mikel; Prieto Suárez, Iria; Espina Antolín, Félix; Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This paper summarizes latest works of Telematic, Networks and Services research group (TNS) of Public University of Navarra in the topics of FIERRO thematic network. Last two papers sent to major conferences are addressed First work shows how self-similar traffic can be generated using Perlin Noise, an algorithm commonly used to generate 2D/3D noise for natural looking graphics. 1-dimension Perlin Noise can be interpreted as network traffic and used to generate long range dependent traffic for network simulation. The algorithm is compared to more classical approach Random Midpoint Displacement showing at traffic generated is similar but can be generated continuously with no fixed block size. Second work presents two novel cloning schemes for video delivery in OBS networks that dramatically improve user perceived content quality. These schemes take into account the special characteristics of compressed video traffic. Analytical and simulation results show up to 40% QoE improvement without a substantial increase in the overall network traffic and without increasing the number of bursts in the network. The results show the strong dependency of this novel cloning scheme on the video traffic structure due to the coding mechanisms.
Open Access
Arquitectura de publicación automatizada de contenidos educativos supervisados en Internet
(1999) Arin Irastorza, María Asunción; Magaña Lizarrondo, Eduardo; Astrain Escola, José Javier; Villadangos Alonso, Jesús; González de Mendívil Moreno, José Ramón; Automática y Computación; Automatika eta Konputazioa
This paper presents an automated publishing architecture of educational and supervised contents over the Internet. The system makes easier the job of publishing educational courses over the network using specific tools that automates the access control (CGI -- Common Gateway Interface), encrypts the information that goes through the net for not being accessed by strangers (SSL – Secure Sockets Layer), gives an statistical control of the usage of the system, and tutors the course. This project is multiplatform, i.e. all the components that integrate the system are available for any operating system (Windows 9X, Solaris, Linux,...) and it is based on the Web.
Open Access
Midiendo retardos y pérdidas en las redes móviles de alta velocidad
(2015) Prieto Suárez, Iria; Izal Azcárate, Mikel; Magaña Lizarrondo, Eduardo; Morató Osés, Daniel; Automática y Computación; Automatika eta Konputazioa
Mobile networks are constantly evolving, but still, due to their nature, it is not trivial to analayse how they face up different kinds of traffic. On the Internet a wide range of services can be found. Usually the majority send large packets, i.e Web services, but others, like VoIP, send small packets. The question is how the mobile networks manage all this traffic. In this work experiments to measure losses and times of sending different packet size bursts are described. Also, preliminary results for experiments with a real network mobile client, are analaysed showing that the performance of the network is different depending on the size of packet.
Open Access
Herramienta de gestión en tiempo real de redes de área extensa
(1998) Magaña Lizarrondo, Eduardo; Aracil Rico, Javier; Villadangos Alonso, Jesús; Automática y Computación; Automatika eta Konputazioa
This paper presents PROMIS, a new network management tool based on a distributed architecture of traffic probes. It allows network managers to monitor traffic from any wide area network segment in real time using a WWW console or a Tcl/Tk graphic interface.
Open Access
On the nature of unused TCP connections in web traffic
(2015) Torres García, Luis Miguel; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Morató Osés, Daniel; Automática y Computación; Automatika eta Konputazioa
The popularity of the web and the requirements introduced by current web content have pushed for the development of new techniques that meet these challenges and improve the experience of the users. In particular, during the last years, web browsers have taken aggressive measures in order to reduce webpage download times. These measures have had a noteworthy effect on the profile of web traffic. One of the most striking consequences is that nowadays, more than 20% of the TCP connections opened by a browser are left unused. In this paper we describe these connections, explain why they happen and use them as a simple way of identifying the traffic of different web browsers.
Open Access
Técnicas eficientes de filtrado y análisis de tráfico para la monitorización continua de redes de comunicaciones
(1999) Ruiz, José Javier; Magaña Lizarrondo, Eduardo; Aracil Rico, Javier; Villadangos Alonso, Jesús; Automática y Computación; Automatika eta Konputazioa
This paper presents an efficient traffic filtering and analysis architecture for network monitoring. Opposed to the usual network monitoring architectures that provide simultaneous filters as requested by managers (packet filters), we propose a different approach that aims at minimizing CPU load by avoiding unnecessary filter duplicates. Such architecture makes it possible to optimize several parallel filters execution and thus is suitable for continuous network monitoring in which it is necessary to keep track of hundreds of filters. This architecture has been implemented in a network-monitoring tool called PROMIS whose main features are detailed in this paper.
Open Access
Garantía de calidad de servicio basada en la predicción del ancho de banda
(2001) Villadangos Alonso, Jesús; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa
This paper presents the architecture and performance evaluation of a neuronal estimator to predict network load in communication networks. System benchmarks are tested with real network traffic picked up from the 155 Mbps ATM Internet connection of the Universidad Pública de Navarra. The system shows good benefits in traffic prediction with 3 and 5 hours of advance. So the system shows characteristic of great interest to carry out the dynamic assignment of bandwidth in Internet Service Providers (ISPs), guaranteeing quality of service hired by the users.
Open Access
Traffic estimation in high-speed communication networks using fuzzy systems
(EUSFLAT, 2001) Magaña Lizarrondo, Eduardo; Villadangos Alonso, Jesús; Astrain Escola, José Javier; Automática y Computación; Automatika eta Konputazioa
We present a practical application of fuzzy systems in communication networks. In this case a fuzzy relational model is developed to estimate the bytes transferred every time unit over a communication link. Such estimation is useful to provide an algorithm to dynamically reserve resources in order to guaranty the quality of service of the communications. In order to evaluate the fuzzy estimator we apply the information about the whole IP packets received at the router of the Public University of Navarra along two months. The estimator predicts the load of the communication link 1, 2, 4 and 6 hours before. The results show that the estimator can be used to dynamically assign bandwidth for communication services.
Open Access
Evaluación de los sistemas inalámbricos 802.11b en entornos de alta movilidad para su implantación en una red de Infostations
(2005) Cayón Alcalde, Juan Ramón; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa
Nowadays, users demand higher bandwidth Internet access with the ability to connect anywhere (or, at least, many-where) at anytime, with no restrictions imposed by mobility or the kind of information (voice or data) to exchange. In this context, we've tried to explore the possibilities of a largely characterized and cheap wireless solution, 802.11b, in a high mobility environment. The performance of 802.11b wireless LANs is well known for indoor and static environments, while their behavior in outdoor and mobile environments has not been explored but from a theoretical point of view. Our work tests an empirical approach to 802.11b real possibilities on a high speed mobile environment. The goal was to check if a mobile station, moving at vehicular speed, was able to communicate with an AP at the roadside. Our results show that it is possible and achieving interesting throughput levels.
Open Access
IP addresses distribution in Internet and its application on reduction methods for IP alias resolution
(IEEE, 2009) García-Jiménez, Santiago; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Morató Osés, Daniel; Automática y Computación; Automatika eta Konputazioa
Discovery of Internet topology is an important and open task. It is difficulted by the high number of networks and internetworking equipments, and even by the dynamic of those interconnections. Mapping Internet at router-level needs to identify IP addresses that belong to the same router. This is called IP address alias resolution and classical methods in the state of the art like Ally need to test IP addresses in pairs. This means a very high cost in traffic generated and time consumption, specially with an increasing topology size. Some methods have been proposed to reduce the number of pairs of IP addresses to compare based on the TTL or IP identifier fields from the IP header. However both need extra traffic and they have problems with the probing distribution between several probing nodes. This paper proposes to use the peculiar distribution of IP addresses in Internet Autonomous Systems in order to reduce the number of IP addresses to compare. The difference between pairs of IP addresses is used to know a priori if they are candidates to be alias with certain probability. Performance evaluation has been made using Planetlab and Etomic measurement platforms. The paper justifies the reduction method, obtaining high reduction ratios without injecting extra traffic in the network and with the possibility to distribute the process for alias resolution.