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  • PPREM: Privacy Preserving REvocation Mechanism for Vehicular Ad Hoc Networks

     Hernández Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    Computer Standards & Interfaces
    Date of publication: 2014-03-01
    Journal article

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    One of the critical security issues of Vehicular Ad Hoc Networks (VANETs) is the revocation of misbehaving vehicles. While essential, revocation checking can leak potentially sensitive information. Road Side Units (RSUs) receiving the certificate status queries could infer the identity of the vehicles posing the query. An important loss of privacy results from the RSUs ability to tie the checking vehicle with the query's target. We propose a Privacy Preserving Revocation mechanism (PPREM) based on a universal one-way accumulator. PPREM provides explicit, concise, authenticated and unforgeable information about the revocation status of each certificate while preserving the users' privacy.

  • Certificate revocation list distribution system for the KAD network

     Caubet Fernandez, Juan; Hernández Gañan, Carlos; Esparza Martin, Oscar; Muñoz Tapia, Jose Luis; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    The Computer journal (paper)
    Date of publication: 2014-02-01
    Journal article

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    Many peer-to-peer (p2p) overlays require certain security services which could be provided through a Public Key Infrastructure. However, these infrastructures are bound up with a revocation system, such as Certificate Revocation Lists (CRLs). A system with a client/server structure, where a Certificate Authority plays a role of a central server, is prone to suffer from common problems of a single point of failure. If only one Authority has to distribute the whole CRL to all users, perhaps several millions in a structured p2p overlay, a bottleneck problem appears. Moreover, in these networks, users often have a set of pseudonyms that are bound to a certificate, which gives rise to two additional issues: issuing the CRL and assuring its freshness. On the one hand, the list size grows exponentially with the number of network users. On the other hand, these lists must be updated more frequently; otherwise the revocation data will not be fresh enough. To solve these problems, we propose a new distributed revocation system for the Kademlia network. Our system distributes CRLs using the overlay itself and, to not compromise the storage of nodes, lists are divided into segments. This mechanism improves the accessibility, increases the availability and guarantees the freshness of the revocation data.

  • A Cross-layer architecture for DVB-S2 Broadband Satellite systems with QoS support

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis
    European Conference European Wireless
    Presentation's date: 2013-04-16
    Presentation of work at congresses

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    In this paper we propose an architecture to provide Quality of Service (QoS) guarantees for DVB-S2 broadband satellite systems. The proposed architecture provides low complexity on its implementation and can seamlessly inter-operate with terrestrial IP networks. The solution is designed in compliance with the ETSI-BSM-QoS framework and provides a detailed design at the Satellite Independent- Satellite Dependent (SI-SD) layers in order to provide QoS guarantees by means of traffic priorities. Particularly, at the SI layers several mechanism are defined to deal with QoS differentiation based on the DiffServ framework. Conversely, at the SD layers the application of different DVB-S2 channel adaptations are assumed. The proposed architecture is evaluated using the NS-2 simulator. The key results show that the implementation of this architecture, enables to keep control of the satellite system load while guaranteeing the QoS levels for the high priority traffic classes even though bandwidth variations due to rain events are experienced.

  • Secure handoffs for V2I communications in 802.11 networks

     Hernández Gañan, Carlos; Reñe Vicente, Sergi; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    ACM Symposium on Performance Evaluation of Wireless Ad Hoc, Sensor, and Ubiquitous Networks
    Presentation's date: 2013-11-04
    Presentation of work at congresses

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    Vehicular ad hoc networks (VANETs) are emerging as a novel paradigm for safety services, supporting real-time applications (e.g., video-streaming, Internet browsing, online gaming, etc.). However, maintaining ubiquitous connectivity remains a challenge due to both high vehicle speed, and non-homogeneous nature of the network access infrastructure. Getting access to the network infrastructure must be controlled and only authorized users should be able to use it. However, the authentication process incurs in a not-negligible delay which can result in packet losses and other issues during handoffs. Hence, a fast and secure handoff scheme is essential. Although some solutions have been given in IEEE 802.11i and 802.11r standards, the handoff latency is still above 50 ms. Other protocols such as CAPWAP and HOKEY include support for fast handoff but have not been evaluated in a vehicular network. In this article, we analyze the security properties and performance of current proposals. Finally, simulations are conducted to date the effectiveness of the handoffs schemes.

  • Impacto de las unidades a pie de carretera en las interferencias en redes vehiculares

     Hernández Gañan, Carlos; Reñé Vicente, Sergi; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    Jornadas de Ingeniería Telemática
    Presentation's date: 2013-10-28
    Presentation of work at congresses

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    Las redes ad hoc vehiculares (VANETs) han emergido como una tecnología clave que posibilita el despliegue diversas aplicaciones. Proporcionar seguridad a los servicios de información y entretenimiento en estos entornos requiere del uso de unidades a pie de la carretera (RSU) como puertas de acceso a los recursos solicitados. Idealmente, las RSUs deben desplegarse para proporcionar conectividad continua. Si bien esto aumenta la capacidad y cobertura, también acarrea un aumento de la interferencia que puede degradar seriamente el rendimiento de la VANET. En este trabajo se estudia el impacto de la interferencia entre RSUs y sostenemos que la versión actual de la norma IEEE 1609.4 no puede hacer frente a la alta densidad vehicular. Extensas simulaciones apoyan las conclusiones obtenidas en este trabajo.

  • Deploying internet protocol security in satellite networks using transmission control protocol performance enhancing proxies

     Caubet Fernandez, Juan; Muñoz Tapia, Jose Luis; Alins Delgado, Juan Jose; Mata Diaz, Jorge; Esparza Martin, Oscar
    International journal of satellite communications and networking
    Date of publication: 2013-03-01
    Journal article

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  • COACH: COllaborative certificate stAtus CHecking mechanism for VANETs

     Hernández Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Hernández Serrano, Juan Bautista; Alins Delgado, Juan Jose
    Journal of network and computer applications
    Date of publication: 2013-09
    Journal article

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    Vehicular Ad Hoc Networks (VANETs) require mechanisms to authenticate messages, identify valid vehicles, and remove misbehaving vehicles. A public key infrastructure (PKI) can be used to provide these functionalities using digital certificates. However, if a vehicle is no longer trusted, its certificates have to be revoked and this status information has to be made available to other vehicles as soon as possible. In this paper, we propose a collaborative certificate status checking mechanism called COACH to efficiently distribute certificate revocation information in VANETs. In COACH, we embed a hash tree in each standard Certificate Revocation List (CRL). This dual structure is called extended-CRL. A node possessing an extended-CRL can respond to certificate status requests without having to send the complete CRL. Instead, the node can send a short response (less than 1 kB) that fits in a single UDP message. Obviously, the substructures included in the short responses are authenticated. This means that any node possessing an extended-CRL can produce short responses that can be authenticated (including Road Side Units or intermediate vehicles). We also propose an extension to the COACH mechanism called EvCOACH that is more efficient than COACH in scenarios with relatively low revocation rates per CRL validity period. To build EvCOACH, we embed an additional hash chain in the extended-CRL. Finally, by conducting a detailed performance evaluation, COACH and EvCOACH are proved to be reliable, efficient, and scalable.

  • Performance evaluation of selected transmission control protocol variants over a digital video broadcasting-second generation broadband satellite multimedia system with QoS

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    International journal of communication systems
    Date of publication: 2013-11-07
    Journal article

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    This paper presents an analysis of several Transmission Control Protocol (TCP) variants working over a digital video broadcasting-second generation (DVB-S2) satellite link with the support of the Differentiated Services (DiffServ) architecture to provide quality of service (QoS). This analysis is carried out using the NS-2 simulator tool. Three TCP variants are considered: SACK TCP, Hybla TCP, and CUBIC TCP. These TCP variants are taken as a starting point because they have proven to be the most suitable variants to deal with long delays present in satellite links. The DVB-S2 link also introduces the challenge of dealing with variable bandwidth, whereas the DiffServ architecture introduces the challenge of dealing with different priorities. In this paper, we propose a DiffServ model that includes a modified queuing mechanism to enhance the goodput of the assured forwarding traffic class. This modified DiffServ model is simulated and tested, considering the interaction of the selected TCP variants. In addition, we present evaluation metrics, significant simulations results, and conclusions about the performance of these TCP variants evaluated over the proposed scenario. As a general conclusion, we show that CUBIC TCP is the TCP variant that shows the best performance in terms of goodput, latency, and friendliness. Copyright © 2012 John Wiley & Sons, Ltd.

  • BECSI: Bandwidth efficient certificate status information distribution mechanism for VANETs

     Hernandez Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Loo, Jonathan; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    Mobile information systems
    Date of publication: 2013-12-04
    Journal article

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    Certificate revocation is a challenging task, especially in mobile network environments such as vehicular ad Hoc networks (VANETs). According to the IEEE 1609.2 security standard for VANETs, public key infrastructure (PKI) will provide this functionality by means of certificate revocation lists (CRLs). When a certificate authority (CA) needs to revoke a certificate, it globally distributes CRLs. Transmitting these lists pose a problem as they require high update frequencies and a lot of bandwidth. In this article, we propose BECSI, a Bandwidth Efficient Certificate Status Information mechanism to efficiently distribute certificate status information (CSI) in VANETs. By means of Merkle hash trees (MHT), BECSI allows to retrieve authenticated CSI not only from the infrastructure but also from vehicles acting as mobile repositories. Since these MHTs are significantly smaller than the CRLs, BECSI reduces the load on the CSI repositories and improves the response time for the vehicles. Additionally, BECSI improves the freshness of the CSI by combining the use of delta-CRLs with MHTs. Thus, vehicles that have cached the most current CRL can download delta-CRLs to have a complete list of revoked certificates. Once a vehicle has the whole list of revoked certificates, it can act as mobile repository.

  • Contributions based on cross-layer design for Quality-of-Service provisioning over DVB-S2/RCS Broadband Satellite Systems  Open access

     Rendon Morales, Elizabeth
    Defense's date: 2013-03-21
    Department of Telematics Engineering, Universitat Politècnica de Catalunya
    Theses

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    Contributions based on cross-layer design for Quality-of-Service provisioning over DVB-S2/RCS Broadband Satellite Systems Nowadays, geostationary (GEO) satellite infrastructure plays a crucial role for the provisioning of IP services. Such infrastructure can provide ubiquity and broadband access, being feasible to reach disperse populations located worldwide within remote areas where terrestrial infrastructure can not be deployed. Nevertheless, due to the expansion of the World Wide Web (WWW), new IP applications such as Voice over IP (VoIP) and multimedia services requires considering different levels of individual packet treatment through the satellite network. This differentiation must include not only the Quality of Service (QoS) parameters to specify packet transmission priorities across the network nodes, but also the required amount of bandwidth assignment to guarantee its transport. In this context, the provisioning of QoS guarantees over GEO satellite systems becomes one of the main research areas of organizations such as the European Space Agency (ESA). Mainly because, their current infrastructures require continuous exploitation, as launching a new communication satellite is associated with excessive costs. Therefore, the support of IP services with QoS guarantees must be developed on the terrestrial segment to enable using the current assets. In this PhD thesis several contributions to improve the QoS provisioning over DVB-S2/RCS Broadband Satellite Systems have been developed. The contributions are based on cross-layer design, following the layered model standardized in the ETSI TR 102 157 and 462. The proposals take into account the drawbacks posed by GEO satellite systems such as delay, losses and bandwidth variations. The first contribution proposes QoSatArt, an architecture defined to improve QoS provisioning among services classes considering the physical layer variations due to the presence of rain events. The design is developed inside the gateway, including the specification of the main functional blocks to provide QoS guarantees and mechanisms to minimize de delay and jitter values experienced at the application layer. Here, a cross-layer design between the physical and the network layer has been proposed, to enforce the QoS specifications based on the available bandwidth. The proposed QoSatArt architecture is evaluated using the NS-2 simulation tool. In addition, the performance analysis of several standard Transmission Control Protocol (TCP) variants is also performed. This is carry out to find the most suitable TCP variant that enhances TCP transmission over a QoS architecture such as the QoSatArt. The second contribution proposes XPLIT, an architecture developed to enhance TCP transmission with QoS for DVB-S2/RCS satellite systems. Complementary to QoSatArt, XPLIT introduces Performance Enhanced Proxies (PEPs), which breaks the end-to-end semantic of TCP connections. However, it considers a cross-layer design between the network layer and the transport layer to enhance TCP transmission while providing them with QoS guarantees. Here, a modified TCP variant called XPLIT-TCP is proposed to send data through the forward and the return channel. XPLIT-TCP uses two control loops (the buffer occupancy and the service rate to provide optimized congestion control functions. The proposed XPLIT architecture is evaluated using the NS-2 simulation tool. Finally, the third contribution of this thesis consists on the development of a unified architecture to provide QoS guarantees based on cross-layer design over broadband satellite systems. It adopts the enhancements proposed by the QoSatArt architecture working at the network layer, in combination with the enhancements proposed by the XPLIT architecture working at the transport layer.

    Actualmente, los satélites Geoestacionarios (GEO) juegan un papel muy importante en la provisión de servicios IP. Esta infraestructura permite proveer ubicuidad y acceso de banda ancha, haciendo posible alcanzar poblaciones dispersas en zonas remotas donde la infraestructura terrestre es inexistente. Sin embargo, en la provisión de aplicaciones como Voz sobre IP (VoIP) y servicios multimedia, es importante considerar el tratamiento diferenciado de paquetes a través de la red satelital. Esta diferenciación debe considerar no solo los requerimientos de Calidad de Servicio (QoS) que especifican las prioridades de los paquetes a través de los nodos de red, si no también el ancho de banda asignado para garantizar su transporte. En este contexto, la provisión de garantías de QoS sobre satélites GEO es una de las Principales áreas de investigación de organizaciones como la Agencia Espacial Europea (ESA) persiguen. Esto se debe principalmente ya que dichas organizaciones requieren la explotación continua de sus activos, dado que lanzar un nuevo satélite al espacio representa costos excesivos. Como resultado, el soporte de servicios IP con calidad de servicio sobre la infraestructura satelital actual es de vital importancia. En esta tesis doctoral se presentan varias contribuciones para el soporte a la Calidad de Servicio en redes DVB-S2/RCS satelitales de banda ancha. Las contribuciones propuestas se basan principalmente en el diseño ”cross-layer” siguiendo el modelo de capas definido y estandarizado en las especificaciones ETSI TR 102 157 [ETS03] y 462 [10205]. Las contribuciones propuestas consideran las limitaciones presentes de los sistemas satelitales GEO como lo son el retardo de propagación, la perdida de paquetes y las variaciones de ancho de banda causados por eventos atmosféricos. La primera contribución propone QoSatArt, una arquitectura definida para mejorar el soporte a la QoS. Esta arquitectura considera las variaciones en la capa física debido a la presencia de eventos de lluvia para priorizar los niveles de QoS. El diseño se desarrolla en el gateway e incluye las especificaciones de los principales elementos funcionales y mecanismos para garantizar la QoS y minimizar el retardo presente en la capa de aplicación. Aquí, se propone un diseño ”cross-layer” entre la capa física y la capa de red, con el objetivo de reforzar las especificaciones de QoS considerando el ancho de banda disponible. La arquitectura QoSatArt es simulada y evaluada empleando la herramienta de simulación NS-2. Adicionalmente, un análisis de desempeño de diversas variantes de TCP (Transmission Control Protocol) es realizado con el objetivo de encontrar la variante de TCP más adecuada para trabajar en un ambiente con QoS como QoSatArt. La segunda contribución propone XPLIT, una arquitectura desarrollada para mejorar las transmisiones TCP con QoS en un sistema satelital DVB-S2/RCS. Complementario a QoSatArt, XPLIT emplea PEPs (Performance Enhanced Proxies), afectando la semántica end-to-end de las conexiones TCP. Sin embargo, XPLIT considera un diseño ”cross-layer” entre la capa de red y la capa de transporte con el objetivo de mejorar las transmisiones TCP considerando los parámetros de QoS como la ocupación de la cola y la tasa de transmisión (_i, _i). Aquí, se propone el uso de una nueva variante de TCP es propuesta llamada XPLIT-TCP, que usa dos bucles para proveer funciones mejoradas en el control de congestión. La arquitectura XPLIT es simulada y evaluada empleando la herramienta de simulación NS-2. Finalmente, la tercera contribución de esta tesis consiste en el desarrollo de un arquitectura unificada para el soporte a la QoS en redes satelitales de banda ancha basada en técnicas ”cross-layer”. Esta arquitectura adopta las mejoras propuestas por QoSatArt en la capa de red en combinación con las mejoras propuestas por XPLIT en la capa de transporte.

  • Toward revocation data handling efficiency in VANETs

     Hernández Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    International Workshop on Communication Technologies for Vehicles
    Presentation's date: 2012
    Presentation of work at congresses

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  • Impact of the revocation service in PKI prices

     Hernandez Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    International Conference on Information and Communications Security
    Presentation's date: 2012
    Presentation of work at congresses

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    The ability to communicate securely is needed for many network applications. Public key infrastructure (PKI) is the most extended solution to verify and confirm the identity of each party involved in any secure transaction and transfer trust over the network. One of the hardest tasks of a certification infrastructure is to manage revocation. Research on this topic has focused on the trade-offs that different revocation mechanisms offer. However, less effort has been paid to understand the benefits of improving the revocation policies. In this paper, we analyze the behavior of the oligopoly of certificate providers that issue digital certificates to clients facing identical independent risks. We found the prices in the equilibrium, and we proof that certificate providers that offer better revocation information are able to impose higher prices to their certificates without sacrificing market share in favor of the other oligarchs. In addition, we show that our model is able to explain the actual tendency of the SSL market where providers with worst QoS are suffering loses.

  • RAR: Risk aware revocation mechanism for vehicular networks

     Hernández Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Silva Cárdenas, Carlos; Bartra Gardini, Gumercindo
    IEEE Vehicular Technology Conference
    Presentation's date: 2012
    Presentation of work at congresses

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    Vehicular Ad Hoc Networks (VANETs) require some mechanism to authenticate messages, identify valid vehicles, and remove misbehaving ones. A Public Key Infrastructure (PKI) can provide this functionality using digital certificates. In PKI, key management and corresponding issuance and revocation of digital certificates is one of the key issues that have to be solved. The IEEE 1609.2 standard states that VANETs will rely on the use of certificate revocation lists (CRLs) to achieve revocation. In this paper, we analyze the problems of using CRLs in these type of networks. Moreover, we describe the Risk Aware Revocation (RAR) mechanism that improves the traditional use of CRLs. RAR takes advantage of the two distinct channel types in VANETs to increase the freshness of the revocation information. Moreover, RAR allows users to gauge the risk of operating in a VANET when using CRLs.

  • On the self-similarity nature of the revocation data

     Hernández Gañan, Carlos; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Alins Delgado, Juan Jose
    International Conference on Information Security
    Presentation's date: 2012-09
    Presentation of work at congresses

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    One of the hardest tasks of a Public Key Infrastructure (PKI) is to manage revocation. Different revocation mechanisms have been proposed to invalidate the credentials of compromised or misbe- having users. All these mechanisms aim to optimize the transmission of revocation data to avoid unnecessary network overhead. To that end, they establish release policies bas ed on the assumption that the revoca- tion data follows uniform or Poisson distribution. Temporal distribution of the revocation data has a significant influence on the performance and scalability of the revocation service. In this paper, we demonstrate that the temporal distribution of the daily number of revoked certificates is statistically self-similar, and that the currently assumed Poisson distribu- tion does not capture the statistical properties of the distribution. None of the commonly used revocation models takes into account this fractal behavior, though such behavior has serious implications for the design, control, and analysis of revocation protocols such as CRL or delta-CRL.

  • Adaptive IP scheduler design to support QoS guarantees over satellite systems

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    Journal of Internet Engineering
    Date of publication: 2012-06
    Journal article

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  • A modeling of certificate revocation and its application to synthesis of revocation traces

     Hernández Gañan, Carlos; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis; Hernández Serrano, Juan Bautista; Esparza Martin, Oscar; Alins Delgado, Juan Jose
    IEEE transactions on information forensics and security
    Date of publication: 2012-12
    Journal article

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    One of the hardest tasks of a public key infrastructure (PKI) is to manage revocation. New communication paradigms push the revocation system to the limit and an accurate resource assessment is necessary before implementing a particular revocation distribution system. In this context, a precise modeling of certificate revocation is necessary. In this article, we analyze empirical data from real CAs to develop an accurate and rigorous model for certificate revocation. One of the key findings of our analysis is that the certificate revocation process is statistically self-similar. The proposed model is based on an autoregressive fractionally integrated moving average (ARFIMA) process. Then, using this model, we show how to build a synthetic revocation generator that can be used in simulations for resource assessment. Finally, we also show that our model produces synthetic revocation traces that are indistinguishable for practical purposes from those corresponding to actual revocations.

    Postprint (author’s final draft)

  • Risk-based decision-making for public key infrastructures using fuzzy logic

     Hernández Gañan, Carlos; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar; Mata Diaz, Jorge; Alins Delgado, Juan Jose
    International journal of innovative computing information and control
    Date of publication: 2012-11-01
    Journal article

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  • QoSatAr: a cross-layer architecture for E2E QoS provisioning over DVB-S2 broadband satellite systems

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    Eurasip journal on wireless communication and networking
    Date of publication: 2012-10-01
    Journal article

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    his article presents QoSatAr, a cross-layer architecture developed to provide end-to-end quality of service (QoS) guarantees for Internet protocol (IP) traffic over the Digital Video Broadcasting-Second generation (DVB-S2) satellite systems. The architecture design is based on a cross-layer optimization between the physical layer and the network layer to provide QoS provisioning based on the bandwidth availability present in the DVB-S2 satellite channel. Our design is developed at the satellite-independent layers, being in compliance with the ETSI-BSM-QoS standards. The architecture is set up inside the gateway, it includes a Re-Queuing Mechanism (RQM) to enhance the goodput of the EF and AF traffic classes and an adaptive IP scheduler to guarantee the high-priority traffic classes taking into account the channel conditions affected by rain events. One of the most important aspect of the architecture design is that QoSatAr is able to guarantee the QoS requirements for specific traffic flows considering a single parameter: the bandwidth availability which is set at the physical layer (considering adaptive code and modulation adaptation) and sent to the network layer by means of a cross-layer optimization. The architecture has been evaluated using the NS-2 simulator. In this article, we present evaluation metrics, extensive simulations results and conclusions about the performance of the proposed QoSatAr when it is evaluated over a DVB-S2 satellite scenario. The key results show that the implementation of this architecture enables to keep control of the satellite system load while guaranteeing the QoS levels for the high-priority traffic classes even when bandwidth variations due to rain events are experienced. Moreover, using the RQM mechanism the user's quality of experience is improved while keeping lower delay and jitter values for the high-priority traffic classes. In particular, the AF goodput is enhanced around 33% over the drop tail scheme (on average).

  • XPLIT: A cross-layer architecture for TCP services over DVB-S2/ETSI QoS BSM

     Alins Delgado, Juan Jose; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis; Rendon Morales, Elizabeth; Esparza Martin, Oscar
    Computer networks
    Date of publication: 2012-01-12
    Journal article

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    This article proposes XPLIT, a new architecture based on TCP cross-layering and splitting for optimizing the transport layer performance in a DVB-S2 satellite link that employs the ETSI QoS Broadband Satellite Multimedia Services (BSM) standard. The main novelty of our proposal is a complete architecture that perfectly fits this new DVB-S2/ETSI QoS BSM scenario. Our architecture includes the design of satellite-optimized cross-layer TCP protocol, called XPLIT-TCP that uses two control loops to properly manage the system load. The proposal has been implemented to be tested in the NS-2 simulator and we include the most interesting performance evaluation results, which show the excellent performance of our architecture for the intended scenario

  • NeuroCast: adaptive multi-source P2P video streaming application for wireless networks

     Hernández Gañan, Carlos; Caubet Fernandez, Juan; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Esparza Martin, Oscar
    International Conference on Wired/Wireless Internet Communications
    Presentation's date: 2011-06-01
    Presentation of work at congresses

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    Streaming consists in distributing media to large audiences over a computer network. Providing a streaming service for wireless mobile nodes presents many challenges. A peer-to-peer (P2P) solution has the big advantage of seamlessly scaling to arbitrary population sizes, as every node that receives the video, while consuming resources, can at the same time offer its own upload bandwidth to serve other nodes. In this paper we present the design and implementation of NeuroCast: an unstructured P2P application for video streaming. NeuroCast implements a robust scheduling algorithm which minimizes the scheduling delay. Moreover, given heterogeneous contents, delays and bandwidths. Thus, NeuroCast becomes suitable for wireless scenarios due to its capability to adapt to changing network conditions.

  • Analysis of TCP variants over a QoS DVB-S2 system

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    ACM International Symposium on Performance Evaluation of Wireless Ad Hoc, Sensor, and Ubiquitous Networks
    Presentation's date: 2011-10-01
    Presentation of work at congresses

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    This paper presents a performance analysis of the TCP protocol considering the DiffServ architecture to provide Quality of Service guarantees working over a Digital Video Broadcasting - Second Generation (DVB-S2) satellite system. The analysis is carried out using the NS-2 simulator tool where three TCP variants are considered: Sack TCP, Hybla TCP and Cubic TCP. The objective is to evaluate the TCP performance taking in to account goodput, friendliness and fairness parameters and the most typical problems presented in a DVB-S2 satellite link such as delay, losses and bandwidth variations.

  • Evaluación de prestaciones de diferentes variantes de TCP en un entorno satelital DVB-S2

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    Jornadas de Ingeniería Telemática1
    Presentation's date: 2011-09-20
    Presentation of work at congresses

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  • Adaptive packet scheduling for the support of QoS over DVB-S2 satellite systems

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    International Conference on Wired/Wireless Internet Communications
    Presentation's date: 2011-06-01
    Presentation of work at congresses

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    This paper presents an adaptive algorithm for managing the weights of a weighted round robin (WRR) scheduler. The weights calculation depends on the capacity variations present in a Digital Video Broadcasting-Second Generation (DVB-S2) satellite link. The algorithm optimizes the bandwidth utilization while satisfying the QoS requirements for different traffic classes. The operation of the proposed algorithm is demonstrated by using the NS-2 simulator environment. The results show that the proposed adaptive WRR algorithm optimizes the bandwidth utilization while enforcing the priority level of each service class even in an extreme reduction of bandwidth caused by rain events.

  • Immunity of power line communications (PLC) in disturbed networks

     Vallbe, Bernat; Balcells Sendra, Josep; Bogonez Franco, Francisco; Mata Diaz, Jorge; Gago Barrio, Javier
    IEEE International Symposium on Industrial Electronics
    Presentation's date: 2011-06-28
    Presentation of work at congresses

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  • Analysis of video streaming performance in vehicular networks

     Reñé, Sergi; Hernández Gañan, Carlos; Caubet Fernandez, Juan; Alins Delgado, Juan Jose; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis
    International Conference on Advanced Communications and Computation
    Presentation's date: 2011-10-28
    Presentation of work at congresses

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    Vehicular Ad-hoc Networks (VANETs) have been mainly motivated for safety applications, but non-safety applications can also be very helpful to impulse vehicular networks. Among non-safety applications, video streaming services can provide attractive features to many applications and can attract a great number of users. However, VANETs high mobility characteristics and packet loss during communications blackouts difficult the deployment of video services in vehicular networks. In this paper, the performance of a video streaming service has been analyzed to study the deployability of a video on demand service in a highway environment for vehicular users. It has been analyzed the packet loss produced by network reconfiguration during handoffs and its influence in the video streamed quality. Using Mobile IP without and with fast handoffs we have gauge the effects of mobility over the video transmission. We show that although fast handoffs techniques minimize blackouts, they limit the deployment of video streaming services in vehicular networks.

  • Access to the full text
    Implementacion de Ipsec en una arquitectura TCP splitting  Open access

     Caubet Fernandez, Juan; Muñoz Tapia, Jose Luis; Alins Delgado, Juan Jose; Mata Diaz, Jorge; Esparza Martin, Oscar
    Reunión Española sobre Criptología y Seguridad de la Información
    Presentation's date: 2010-09-07
    Presentation of work at congresses

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    El rendimiento de las aplicaciones que utilizan el protocolo de transporte TCP (Transmission Control Protocol) sobre enlaces vía satélite tiene una degradación significativa. Esto se debe principalmente a que el algoritmo de control de congestión estándar de TCP no es adecuado para superar las deficiencias de las redes satelitales. TCP splitting es una solución prometedora para mejorar el rendimiento general de TCP, incluso en el segmento satelital. La división de la conexión TCP se logra mediante la instalación de dos PEPs (Performance Enhancement Proxies) en los extremos del segmento satelital. Sin embargo, la división de TCP entra en conflicto con IPsec. Si el cifrado y/o la autenticación son aplicados sobre los datagramas IP, el PEP no puede manipular las correspondientes cabeceras IP y TCP para dividir las conexiones TCP. En este trabajo presentamos tres propuestas para implementar IPsec en un escenario TCP splitting, proporcionando los servicios de seguridad habituales y un buen rendimiento en la conexión vía satélite. La idea básica es permitir a los PEPs manipular las cabeceras IP y TCP en función del nivel de confianza que los usuarios tengan en ellos.

  • Transmisión de datos: problemas resueltos

     Aguilar Igartua, Mónica; Forné, Jordi; Mata Diaz, Jorge; Rico Novella, Francisco Jose; Rojas Espinosa, Alfonso; Soriano Ibáñez, Miguel
    Date of publication: 2010-11
    Book

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  • Cross-layer architecture for TCP splitting in the return channel over satellite networks

     Rendon Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Esparza Martin, Oscar
    IEEE International Symposium on Wireless Communication Systems
    Presentation's date: 2009-09
    Presentation of work at congresses

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  • A mechanism to avoid collusion attacks based on code passing in mobile agent systems

     Jaimez, Marc; Esparza Martin, Oscar; Muñoz Tapia, Jose Luis; Alins Delgado, Juan Jose; Mata Diaz, Jorge
    Workshop in Information Security Theory and Practice
    Presentation of work at congresses

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  • PROVISION SEGURA DE SERVICIOS SOBRE EL P2P (P2PSEC)

     Pegueroles Valles, Josep Rafel; Fernandez Muñoz, Marcel; Mata Diaz, Jorge; Martin Faus, Isabel Victoria; León Abarca, Olga; Esparza Martin, Oscar; Forga Alberich, Jordi; Hernández Serrano, Juan Bautista; Rico Novella, Francisco Jose; Cruz Llopis, Luis Javier de La; Alins Delgado, Juan Jose; Muñoz Tapia, Jose Luis; Soriano Ibáñez, Miguel
    Participation in a competitive project

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  • Modelado y análisis transitorio de un sistema de distribución de vídeo bajo demanda

     Martin Faus, Isabel Victoria
    Defense's date: 2008-07-21
    Department of Telematics Engineering, Universitat Politècnica de Catalunya
    Theses

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  • IP-friendly cross-layer optimization of adaptive satellite systems

     Albiol, L; Alins Delgado, Juan Jose; Cebrian Diaz, Juan Alfonso; Mata Diaz, Jorge; Vázquez, M A Castro; Vieira, F
    ESA Workshop Advanced Studies on DVB-RCS 2007
    Presentation of work at congresses

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  • Diseño de Diferentes Clases de Usuarios en un Servicio Video-Streaming Adaptativo

     Isabel, V Martín; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    Jornadas de Ingeniería Telemática
    Presentation of work at congresses

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  • CRISALIDA (Convergencia de Redes Inteligentes y Seguras en Aplicaciones Eléctricas Innovando en Diseño Ambiental)

     Balcells Sendra, Josep; Gago Barrio, Javier; Gonzalez Diez, David; Lamich Arocas, Manuel; Bogonez Franco, Francisco; Mata Diaz, Jorge; Muñoz Tapia, Jose Luis; Alins Delgado, Juan Jose; Esparza Martin, Oscar
    Participation in a competitive project

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  • Design of an Adaptive-Rate Video-Streaming Service with Different Classes of Users

     Martin Faus, Isabel Victoria; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    IFIP International Federation for Information Processing
    Date of publication: 2006-08
    Journal article

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  • IP-friendly cross-layer optimization of DVB-S2/RCS

     Albiol, L; Alins Delgado, Juan Jose; Cebrian Diaz, Juan Alfonso; Mata Diaz, Jorge; Morell, A; Morlet, C; Seco, G; Vázquez, M A Castro; Vieira, F
    International Workshop on Signal Processing for Space Communications
    Presentation of work at congresses

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  • Design of an Adaptive-Rate Video-Streaming Service with Different Classes of Users

     Martin Faus, Isabel Victoria; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    IFIP 19th World Computer Congress, TC-6, 5th IFIP International Conference on Network Control and Engineering for QoS, Security and Mobility
    Presentation of work at congresses

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  • Video Streaming With Quality Adaptation Using Collaborative Active Gris Networks

     Peláez, J C; Mata Diaz, Jorge
    Buran
    Date of publication: 2005-09
    Journal article

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  • Performability Analysis of an Adaptive-Rate Video-Streaming Service in End-to-End QoS Scenarios

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    Lecture notes in computer science
    Date of publication: 2005-10
    Journal article

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  • QoS Provision for Video-Streaming Applications over Ad Hoc Networks

     Carrascal Frías, Víctor; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    The International Conference on "Computer as a tool"
    Presentation of work at congresses

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  • Performability Analysis of an Adaptive-Rate Video-Streaming Service in End-to-End QoS scenarios

     Martín, I V; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    16th IFIP/IEEE International Workshop on Distributed Systems: Operations and Management
    Presentation of work at congresses

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  • SECONNET. Plataforma Distribuida Para Comercio Electronico Seguro De Contenidos Multimedia Sobre Redes Heterogeneas De Banda Ancha

     Soriano Ibáñez, Miguel; Aguilar Igartua, Mónica; Mata Diaz, Jorge; Esparza Martin, Oscar; Muñoz Tapia, Jose Luis; Pegueroles Valles, Josep Rafel; Postigo Boix, Marcos; Hernández Serrano, Juan Bautista; Fernandez Muñoz, Marcel
    Participation in a competitive project

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  • Contribución a la transmisión de video en redes IP con calidad de servicio

     Alins Delgado, Juan Jose
    Defense's date: 2004-09-17
    Department of Telematics Engineering, Universitat Politècnica de Catalunya
    Theses

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  • Modelling an Adaptive-Rate Video-Streaming Service Using Markov-Rewards Models

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    First International Conference on Quality of Service in Heterogeneous Wired and Wireless Networks
    Presentation of work at congresses

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  • A Policy-based Management Solution towards QoS-aware Video Streaming Services in Heterogeneous Environments

     Rubio-Loyola, Javier; Rubio Loyola, Javier; Serrat Fernandez, Juan; Mata Diaz, Jorge; Martin Faus, Isabel Victoria; Casals, Fidel
    First International Conference on Quality of Service in Heterogeneous Wired and Wireless Networks
    Presentation of work at congresses

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  • Evaluación de un Servicio Video-Streaming Utilizando Modelos Markovianos con Recompensas

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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  • Analytical Definition of SLA Parameters in a Video-On-Demand Service

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    2004 12th IEEE International Conference on Networks
    Presentation of work at congresses

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  • Definición Analítica de Parámetros SLA en un Servicio de Video Bajo Demanda

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Mata Diaz, Jorge
    Simposium Nacional de la Unión Científica Internacional de Radio
    Presentation of work at congresses

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  • Modelado Semántico y Ubicuo del Comercio Electrónico mediante Web Services

     Peláez, J C; Mata Diaz, Jorge
    Buran
    Date of publication: 2003-12
    Journal article

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  • Modelado y Análisis Transitorio de un Sistema de Distribución de Vídeo bajo Demanda

     Martin Faus, Isabel Victoria; Alins Delgado, Juan Jose; Aguilar Igartua, Mónica; Vallejos, R; Cruz Llopis, Luis Javier de La; Mata Diaz, Jorge
    Jornadas de Ingeniería Telemática
    Presentation of work at congresses

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