Browsing by Author "Esparza Martín, Óscar"Més informacióMés informació

Now showing items 1-20 of 52

    • A game theoretic trust model for on-line distributed evolution of cooperation in MANETs 

      Mejía Fajardo, Marcela; Peña Traslaviña, Néstor; Muñoz Tapia, José Luis; Esparza Martín, Óscar; Alzate Monroy, Marco (2011-01-13)
      Article
      Restricted access - publisher's policy
      Cooperation among nodes is fundamental for the operation of mobile ad hoc networks(MANETs). In such networks, there could be selfish nodes that use resources from other nodes to send their packets but that do not offer ...

    • A model for revocation forecasting in public-key infrastructures 

      Hernández Gañan, Carlos; Mata Diaz, Jorge; Muñoz Tapia, José Luis; Esparza Martín, Óscar; Alins Delgado, Juan José (2015-05-01)
      Article
      Open Access
      One of the hardest tasks of a certification infrastructure is to manage revocation. This process consists in collecting and making the revocation status of certificates available to users. Research on this topic has focused ...

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

      Hernández Gañán, Carlos; Mata Diaz, Jorge; Muñoz Tapia, José Luis; Hernández Serrano, Juan; Esparza Martín, Óscar; Alins Delgado, Juan José (2012)
      Article
      Restricted access - publisher's policy
      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 protocol for data exchange with free samples using smart contracts 

      Genés Durán, Rafael; Hernández Serrano, Juan; Esparza Martín, Óscar; Soriano Ibáñez, Miguel; Muñoz Tapia, José Luis; Bellés Muñoz, Marta (Jornadas de Ingeniería Telemática (JITEL), 2021)
      Conference report
      Open Access
      Distrust between data providers and data consumers is one of the main obstacles hampering digitaldata commerce to take off. Data providers want to get paid for what they offer, while data consumers want to know exactly ...

    • A review of trust modeling in ad hoc networks 

      Mejia, M; Peña, N; Muñoz Tapia, José Luis; Esparza Martín, Óscar (2009-01)
      Article
      Restricted access - publisher's policy
      Findings The study identifies the main components that a trust model must provide, and compares the way they are implemented. It finds that the lack of unity in the different proposed approaches makes it difficult to ...

    • A simple closed-form approximation for the packet loss rate of a TCP connection over wireless links 

      Mata Diaz, Jorge; Alins Delgado, Juan José; Muñoz Tapia, José Luis; Esparza Martín, Óscar (2014-09-15)
      Article
      Open Access
      This letter presents a new and simple model for a TCP flow experiencing random packet losses due to both transmission errors and congestion events. From this model, we will derive a straightforward expression of a unified ...

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

      Rendón Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan José; Muñoz Tapia, José Luis; Esparza Martín, Óscar (2012-06)
      Article
      Open Access
      This paper presents an adaptive algorithm for man-aging the weight values of the Weighted Round Robin (WRR)scheduler to provide End-to-End (E2E) Quality of Service (QoS)guarantees for Broadband satellite ...

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

      Rendón Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan José; Muñoz Tapia, José Luis; Esparza Martín, Óscar (Springer Verlag, 2011)
      Conference report
      Restricted access - publisher's policy
      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 ...

    • An infrastructure for detecting and punishing malicious hosts using mobile agent watermarking 

      Esparza Martín, Óscar; Muñoz Tapia, José Luis; Tomás Buliart, Joan; Soriano Ibáñez, Miguel (2010-04-02)
      Article
      Open Access
      Mobile agents are software entities consisting of code, data, and state that can migrate autonomously from host to host executing their code. In such scenario there are some security issues that must be considered. In ...

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

      Rendón Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan José; Muñoz Tapia, José Luis; Esparza Martín, Óscar (ACM Press. Association for Computing Machinery, 2011)
      Conference report
      Restricted access - publisher's policy
      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 ...

    • Certificate revocation system implementation based on the Merkle Hash Tree 

      Muñoz Tapia, José Luis; Forné Muñoz, Jorge; Esparza Martín, Óscar; Soriano Ibáñez, Miguel (2004-01)
      Article
      Restricted access - publisher's policy
      Public-key cryptography is widely used to provide Internet security services. The public-key infrastructure (PKI) is the infrastructure that supports the public-key cryptography, and the revocation of certificates implies ...

    • CERVANTES - A certificate validation test-bed 

      Muñoz Tapia, José Luis; Forné Muñoz, Jorge; Esparza Martín, Óscar; Soriano Ibáñez, Miguel (Springer Berlin / Heidelberg, 2004)
      Conference report
      Restricted access - publisher's policy
      Certificate validation is one of the toughest scalability problems of the PKI. The goal of this paper is to introduce a Java platform for certificate revocation called CERVANTES. CERVANTES pretends to be an easy to extend ...

    • COACH: COllaborative certificate stAtus CHecking mechanism for VANETs 

      Hernández Gañán, Carlos; Muñoz Tapia, José Luis; Esparza Martín, Óscar; Mata Diaz, Jorge; Hernández Serrano, Juan; Alins Delgado, Juan José (2011-11-01)
      Article
      Restricted access - publisher's policy
      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 ...

    • Contribución a la protección de agentes móviles frente a hosts maliciosos. Detección de ataques y políticas de castigo 

      Esparza Martín, Óscar (Universitat Politècnica de Catalunya, 2004-07-07)
      Doctoral thesis
      Open Access
      Este trabajo presenta tanto el estado del arte como el análisis de las principales propuestas de protección de agentes móviles frente a los ataques de la plataforma de ejecución. La comprensión del problema de los hosts ...

    • Cross-layer packet scheduler for QoS support over digital video broadcasting-second generation broadband satellite systems 

      Rendón Morales, Elizabeth; Mata Diaz, Jorge; Alins Delgado, Juan José; Muñoz Tapia, José Luis; Esparza Martín, Óscar (2014-10-01)
      Article
      Restricted access - publisher's policy
      This article presents a cross-layer packet scheduler to provide end-to-end QoS guarantees for Digital Video Broadcasting-Second Generation (DVB-S2) broadband satellite systems. The scheduler design is based on a cross-layer ...

    • DECADE: Distributed Emergent Cooperation through ADaptive Evolution in mobile ad hoc networks 

      Mejía Fajardo, Marcela; Peña Traslaviña, Néstor; Muñoz Tapia, José Luis; Esparza Martín, Óscar; Alzate Monroy, Marco (Elsevier, 2012-09)
      Article
      Restricted access - publisher's policy
      The scarce resources of a mobile ad hoc network (MANET) should not be wasted attending selfish nodes (those nodes that use resources from other nodes to send their own packets, without offering their own resources to forward ...

    • DEFS - Data exchange with Free Sample Protocol 

      Genés Durán, Rafael; Hernández Serrano, Juan; Esparza Martín, Óscar; Bellés Muñoz, Marta; Muñoz Tapia, José Luis (2021-06-17)
      Article
      Open Access
      Distrust between data providers and data consumers is one of the main obstacles hampering digital-data commerce to take off. Data providers want to get paid for what they offer, while data consumers want to know exactly ...

    • Design and implementation of a lightweight online certificate validation service 

      Muñoz Tapia, José Luis; Esparza Martín, Óscar; Forné Muñoz, Jorge; Pallarès Segarra, Esteve (2009-07)
      Article
      Restricted access - publisher's policy
      A PKI (public key infrastructure) provides for a digital certificate that can identify an individual or an organization. However, the existence of a certificate is a necessary but not sufficient evidence for its validity. ...

    • EPA: An efficient and privacy-aware revocation mechanism for vehicular ad hoc networks 

      Hernández Gañan, Carlos; Muñoz Tapia, José Luis; Esparza Martín, Óscar; Mata Diaz, Jorge; Alins Delgado, Juan José (Elsevier, 2015-08-01)
      Article
      Open Access
      Security is vital for the reliable operation of vehicular ad hoc networks (VANETs). One of the critical security issues is the revocation of misbehaving vehicles. While essential, revocation checking can leak private ...

    • Evaluation of cryptographic capabilities for the Android platform 

      Gonzalez Peon, David; Esparza Martín, Óscar; Muñoz Tapia, José Luis; Alins Delgado, Juan José; Mata Diaz, Jorge (Springer, 2015)
      Conference report
      Restricted access - publisher's policy
      Future networks will be formed by millions of devices, many of them mobile, sharing information and running applications. Android is currently the most widely used operating system in smartphones, and it is becoming more ...