An emulation of VoD services using virtual network environments

Virtualization platforms are a viable alternative for the implementation of IP network experimentation environments. These platforms facilitate the conducting of tests as if a real environment were used and therefore can reduce the risk of failure as well as investment and experimentation costs. This paper proposes to develop a method to improve the results obtained in virtual network environments, trying to resemble those obtained in a real environment. To carry this out, we have emulated a video-on-demand service over ADSL using Xen as a virtualization tool, just as it would have been through a real ADSL connection. Connectivity, IP addressing, switching, routing and video streaming were tested to check the functionality of virtual network environments. Then, the bandwidth, the delay, and the inter-arrival time of video streaming packets were measured both in real and virtual environments. Finally, these parameters were tuned in the virtual network environments obtaining a similar behavior in clients and servers of both cases

Software-driven definition of virtual testbeds to validate emergent network technologies

This paper is an extended version of our paper published in XIII Jornadas de Ingeniería Telemática (JITEL 2017), Valencia, Spain, 27–29 September 2017, “Definición de Testbeds Virtualizados Utilizando Perfiles de Actividad de Red”The lack of privileged access to emergent and operational deployments is one of the key matters during validation and testing of novel telecommunication systems and technologies. This matter jeopardizes the repeatability of experiments, which results in burdens for innovation and research in these areas. In this light, we present a method and architecture to make the software-driven definition of virtual testbeds easier. As distinguishing features, our proposal can mimic operational deployments by using high-dimensional activity patterns. These activity patterns shape the effect of a control module that triggers agents for the generation of network traffic. This solution exploits the capabilities of network emulation and virtualization systems, which nowadays can be easily deployed in commodity servers. With this, we accomplish a reproducible definition of realistic experimental conditions and the introduction of real agent implementations in a cost-effective fashion. We evaluate our solution in a case study that is comprised of the validation of a network-monitoring tool for Voice over IP (VoIP) deployments. Our experimental results support the viability of the method and illustrate how this formulation can improve the experimentation in emergent technologies.This work has been partially funded by the SpanishMinistry of Economy and Competitiveness and the European Regional Development Fund under the projects TRÁFICA (MINECO/FEDER TEC2015-69417-C2-1-R) and RACING DRONES (MINECO/FEDER RTC-2016-4744-7

Estimation of the parameters of token-buckets in multi-hop environments

Bandwidth verification in shaping scenarios receives much attention of both operators and clients because of its impact on Quality of Service (QoS). As a result, measuring shapers’ parameters, namely the Committed Information Rate (CIR), Peak Information Rate (PIR) and Maximum Burst Size (MBS), is a relevant issue when it comes to assess QoS. In this paper, we present a novel algorithm, TBCheck, which serves to accurately measure such parameters with minimal intrusiveness. These measurements are the cornerstone for the validation of Service Level Agreements (SLA) with multiple shaping elements along an end-to-end path. As a further outcome of this measurement method, we define a formal taxonomy of multi-hop shaping scenarios. A thorough performance evaluation covering the latter taxonomy shows the advantages of TBCheck compared to other tools in the state of the art, yielding more accurate results even in the presence of cross-traffic. Additionally, our findings show that MBS estimation is unfeasible when the link load is high, regardless the measurement technique, because the token-bucket will always be empty. Consequently, we propose an estimation policy which maximizes the accuracy by measuring CIR during busy hours and PIR and MBS during off-peak hoursThis work was 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

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

Factor analysis of Internet traffic destinations from similar source networks

This article is (©) Emerald Group Publishing and permission has been granted for this version to appear here (http://www.emeraldinsight.com/doi/full/10.1108/10662241211199951). Emerald does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Emerald Group Publishing Limited.Purpose – This study aims to assess whether similar user populations in the Internet produce similar geographical traffic destination patterns on a per-country basis. Design/methodology/approach – We have collected a country-wide NetFlow trace, which encompasses the whole Spanish academic network, which comprises more than 350 institutions and one million users, during four months. Such trace comprises several similar campus networks in terms of population size and structure. To compare their behaviors, we propose a mixture model, which is primarily based on the Zipf-Mandelbrot power law to capture the heavy-tailed nature of the per-country traffic distribution. Then, factor analysis is performed to understand the relation between the response variable, number of bytes or packets per day, with dependent variables such as the source IP network, traffic direction, and country. Findings – Surprisingly, the results show that the geographical distribution is strongly dependent on the source IP network. Furthermore, even though there are thousands of users in a typical campus network, it turns out that the aggregation level which is required to observe a stable geographical pattern is even larger. Consequently, our results show a slow convergence rate to the domain of attraction of the model, specifically, we have found that at least 35 days worth of data are necessary to reach stability of the model’s estimated parameters. Practical implications – Based on these findings, conclusions drawn for one network cannot be directly extrapolated to different ones. Therefore, ISPs’ traffic measurement campaigns should include an extensive set of networks to cope with the space diversity, and also encompass a significant period of time due to the large transient time. Originality/value – Current state of the art includes some analysis of geographical patterns, but not comparisons between networks with similar populations. Such comparison can be useful for the design of Content Distribution Networks and the cost-optimization of peering agreements.This work has been partially funded by the Spanish Ministry of Education and Science under project ANFORA (TEC2009-13385), European Union CELTIC initiative program under project TRAMMS, European Union project OneLab, and the F.P.U. and F.P.I. Research Fellowship programs of Spain. The authors would also like to thank the anonymous reviewers who helped us to improve the quality of the paper

Application of ontologies for the integration of network monitoring platforms

This is an electronic version of the paper presented at the European Workshop on Mechanisms for Mastering Future Internet, held in Salzburg on 2008This paper presents an ontology-based approach to integrate the measurements provided by different network monitoring tools and platforms. The combination of such measurements is valuable to network operators, enabling the development of new management applications. The use of ontologies provides some advantages over current syntactic solutions: classification, inference and querying capabilities are some of them. Moreover, they can reduce the complexity of information integration, providing solutions that can be applied to existing network monitoring infrastructures.This work has been partially funded by the European Union under the project FP7-MOMENT (INFSO-ICT-215225)

Utilidad de los flujos NetFlow de RedIRIS para análisis de una red académica

La tecnología Netflow se encuentra actualmente desplegada en la mayoría de los routers de las redes comerciales. Dicha tecnología permite registrar los flujos que atraviesan la red, contando el número de bytes y paquetes que se transmiten entre dos equipos, lo cual puede ser útil para diversas aplicaciones. Este trabajo muestra la utilidad y aplicabilidad a la gestión de los flujos de red. En concreto, se presenta cómo los registros de flujos de red que captura RedIRIS en los nodos autonómicos pueden resultar de interés para monitorizar redes y como herramienta de obtención de medidas de la red para su posterior análisis con múltiples fines. Para ello, se ha implementado una aplicación que accede a estos registros, previamente procesados, y muestra de forma sencilla un conjunto de medidas y estadísticas para la mayoría de las universidades conectadas a RedIRIS

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

Online detection of pathological TCP flows with retransmissions in high-speed networks

Online Quality of Service (QoS) assessment in high speed networks is one of the key concerns for service providers, namely to detect QoS degradation on-the-fly as soon as possible and avoid customers’ complaints. In this regard, a Key Performance Indicator (KPI) is the number of TCP retransmissions per flow, which is related to packet losses or increased network and/or client/server latency. However, to accurately detect TCP retransmissions the whole sequence number list should be tracked which is a challenging task in multi-Gb/s networks. In this paper we show that the simplest approach of counting as a retransmission a packet whose sequence number is smaller than the previous one is enough to detect pathological flows with severe retransmissions. Such a lightweight approach eliminates the need of tracking the whole TCP flow history, which severely restricts traffic analysis throughput. Our findings show that low False Positive Rates (FPR) and False Negative Rates (FNR) can be achieved in the detection of such pathological flows with severe retransmissions, which are of paramount importance for QoS monitoring. Most importantly, we show that live detection of such pathological flows at 10 Gb/s rate per processing core is feasibleThis work has been partially funded by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund under the projects TRÁFICA (MINECO/ FEDER TEC2015-69417-C2-1-R), Preproceso Inteligente de Tráfico (MINECO / FEDER TEC2015-69417-C2-2-R) and RACING DRONES (MINECO / FEDER RTC-2016-4744-7

Implementation of multi-layer techniques using FEDERICA, PASITO and OneLab network infrastructures

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. V. López, J. L. Añamuro, V. Moreno, J. E. L. De Vergara, J. Aracil, C. García, J. P. Fernández-Palacios, and M. Izal, "Implementation of multi-layer techniques using FEDERICA, PASITO and OneLab network infrastructures", in 17th IEEE International Conference on Networks, ICON 2011, p. 89-94This paper describes an implementation of multilayer techniques using the network infrastructure provided by FEDERICA, PASITO and OneLab projects. FEDERICA project provides a network infrastructure, based on virtualization capabilities in both network and computing resources, which creates custom-made virtual environments. PASITO is a layer- 2 network that connects universities and research centers in Spain. OneLab measurements tools allow carrying out highaccuracy active network measurements. Thanks to FEDERICA and PASITO, we have a multi-layer architecture where the traffic is routed based on the measurements of OneLab equipment. To carry out this experiment, we have developed a Multi-layer Traffic Engineering manager and an implementation of the Path Computation Element Protocol to solve the lack of a control plane in IP oriented networks. This work shows the feasibility of multilayer techniques as a convenient solution for network operators and it validates our Path Computation Element implementation.This work has been partially funded by the Spanish Ministry of Education and Science under project ANFORA (TEC2009-13385), by the Spanish Ministry of Industry, Tourism and Trade under PASITO project, and by the European Union under project OneLab2 (FP7-224263). Authors would like to thank Mauro Campanella (GARR, the project coordinator of FEDERICA) and Miguel Angel Sotos (RedIris) for their support to carry out this work