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
The European Traffic Observatory Measurement Infraestructure (ETOMIC): a testbed for universal active and passive measurements
(IEEE, 2005) Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Aracil Rico, Javier; Naranjo Abad, Francisco José; Alonso Camaró, Ulisses; Astiz Saldaña, Francisco Javier; Vattay, Gábor; Csabai, István; Hága, Péter; Simon, Gábor; Stéger, József; Automática y Computación; Automatika eta Konputazioa
The European Traffic Observatory is a European Union VI Framework Program sponsored effort, within the Integrated Project EVERGROW, that aims at providing a paneuropean traffic measurement infrastructure with highprecision, GPS-synchronized monitoring nodes. This paper describes the system and node architectures, together with the management system. On the other hand, we also present the testing platform that is currently being used for testing ETOMIC nodes before actual deployment.
Open Access
Multiresolution analysis of optical burst switching traffic
(IEEE, 2003) Aracil Rico, Javier; Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Automática y Computación; Automatika eta Konputazioa
In this paper, a Multiresolution Analysis is conducted in order to study the self-similar features of Optical Burst Switching (OBS) traffi c. The scenario consists of an OBS backbone with input traffic from a large number of Internet users, that generate Poisson-arriving heavytailed bursts. The results show that long-range dependence is preserved at timescales longer than the burst assembly timeout value while the traffic variability at short timescales is increased.
Open Access
The ETOMIC active probing infrastructure: demo proposal
(2006) Csabai, István; Hága, Péter; Simon, Gábor; Stéger, József; Vattay, Gábor; Magaña Lizarrondo, Eduardo; Morató Osés, Daniel; Izal Azcárate, Mikel; Aracil Rico, Javier; Automática y Computación; Automatika eta Konputazioa
ETOMIC (www.etomic.org) is a European Union sponsored effort, that aims at providing a Paneuropean traffic measurement infrastructure. This infrastructure contains 15 PC based active probing nodes equipped with high-precision, sending capable DAG cards and GPS receivers to achieve time synchronization. Such cards are specifically designed to transmit packet trains with strict timing, in the range of nanoseconds. Every kind of active probing techniques can be applied on the nodes, from the quite simple ping application to the complex network tomography methods which are based on the synchronized sending capability of the DAG cards. The measurement nodes are centrally managed via a web platform, where the new arbitrary measurement jobs can be uploaded to and handled. The management system schedules the jobs and does the maintenance tasks. Now, the infrastructure is opened to the networking community. This paper describes the node architectures, the management system, and the proposed conference demonstration.
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
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
Predicción de tráfico de Internet and aplicaciones
(2001) Bernal, I.; Aracil Rico, Javier; Morató Osés, Daniel; Izal Azcárate, Mikel; Magaña Lizarrondo, Eduardo; Díez Marca, L. A.; Automática y Computación; Automatika eta Konputazioa
In this paper we focus on traffic prediction as a means to achieve dynamic bandwidth allocation in a generic Internet link. Our findings show that coarse prediction (bytes per interval) proves advantageous to perform dynamic link dimensioning, even if we consider a part of the top traffic producers in the traffic predictor.
Open Access
Delay-throughput curves for timer-based OBS burstifiers with light load
(IEEE, 2006) Izal Azcárate, Mikel; Aracil Rico, Javier; Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Automática y Computación; Automatika eta Konputazioa
The OBS burstifier delay-throughput curves are analyzed in this paper. The burstifier incorporates a timer-based scheme with minimum burst size, i. e., bursts are subject to padding in light-load scenarios. Precisely, due to this padding effect, the burstifier normalized throughput may not be equal to unity. Conversely, in a high-load scenario, padding will seldom occur. For the interesting light-load scenario, the throughput delay curves are derived and the obtained results are assessed against those obtained by trace-driven simulation. The influence of long-range dependence and instantaneous variability is analyzed to conclude that there is a threshold timeout value that makes the throughput curves flatten out to unity. This result motivates the introduction of adaptive burstification algorithms, that provide a timeout value that minimizes delay, yet keeping the throughput very close to unity. The dependence of such optimum timeout value with traffic long-range dependence and instantaneous burstiness is discussed. Finally, three different adaptive timeout algorithms are proposed, that tradeoff complexity versus accuracy.
Open Access
Approximations for end-to-end delay analysis in OBS networks with light load
(IEEE, 2004) Morató Osés, Daniel; Magaña Lizarrondo, Eduardo; Izal Azcárate, Mikel; Automática y Computación; Automatika eta Konputazioa
In this paper we provide an analysis of end-to-end delay in OBS networks and a large deviations approximation. The analysis is based on an exponential approximation of the OBS router blocking time and on the assumption of Poisson arrivals in routers along the path from source to destination. On the other hand, a lightload assumption is performed, namely, waiting time is mainly due to residual life of the output wavelengths and not to buffering.
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.