Jorge Mata - Academia.edu (original) (raw)
Papers by Jorge Mata
ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN network... more ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN networks include the transmission of variable bit rate (VBR) video traffic. Generally, the nature of this kind of services implies the need of a high quality of service (QoS). Unfortunately, to provide this high QoS to the VBR video traffic with a high efficiency in bandwidth utilization is not a trivial problem. This is due to the bursty nature of the VBR video traffic on different time scales. This traffic behavior is named self-similarity. In order to improve channel utilization, some services with bandwidth renegotiation have been proposed. In this work, a new mechanism to accomplish bandwidth renegotiation over ATM networks for VBR video traffic is presented. The mechanism is based on a previous characterization of the MPEG VBR video traffic at the group of pictures (GoP) level by means of a bidimensional Markov modulated fluid process (MMFP). A new element, with supervision and control functions, is proposed and validated. Moreover, the achieved benefits in terms of the bandwidth gain that can be expected with the renegotiation system are analytically computed using the fluid flow approximation. Finally, the applicability of the supervisor and controller elements and its parameters are studied using four long MPEG VBR sequences
TDX (Tesis Doctorals en Xarxa), Nov 19, 1996
En esta tesis se trata el problema de integración de servicios en redes ATM. En particular, el tr... more En esta tesis se trata el problema de integración de servicios en redes ATM. En particular, el trabajo se centra en los servicios que incorporan información de vídeo digital.La tesis se compone en cinco capítulos. El primer capítulo presenta el escenario y la motivación en el que se enmarca este trabajo, introduciéndose las técnicas y conceptos empleados para su desarrollo. En los tres capítulos centrales se formulan los problemas actuales tratados en esta tesis y se discuten las soluciones planteadas y estandarizadas hasta el momento. Asimismo, se proponen nuevas maneras de abordar cada problemática presentando en cada caso una solución contrastada. Finalmente, en el último capítulo se enumeran las conclusiones obtenidas y se proponen nuevas líneas de investigación derivadas del presente estudio. El trabajo desarrollado puede estructurarse en tres fases asociadas con la presentación realizada en los tres capitulos centrales:i ) En el capítulo 2 se presentan las distintas técnicas e...
Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traf... more Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traffic coming from variable bit rate video (VBR) codecs1, which are capable of maintaining a constant picture quality of the decoded image. The characterization of such VBR video sources becomes important in the analysis and design of Broadband Integrated Services Digital Networks (B-ISDN). The network architecture and its characteristics, such as cell-loss probabilities, transmission delay, high-speed statistical multiplexing gain, buffering, etc., are strongly related to the statistical properties of the sources and the coding schemes involved. On the other hand, a characterization of the traffic generated by a VBR source is necessary in order to allocate resources in ATM networks, as well as, to keep a satisfactory quality of service (QoS). In the call establishment phase, service requirements are negotiated between the user and the network to establish a Traffic Contract. The source tra...
Fifth IEEE International Workshop on Computer-Aided Modeling, Analysis, and Design of Communication Links and Networks, 1994
First International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks
Seamless Interconnection for Universal Services. Global Telecommunications Conference. GLOBECOM'99. (Cat. No.99CH37042)
ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN network... more ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN networks include the transmission of variable bit rate (VBR) video traffic. Generally, the nature of this kind of services implies the need of a high quality of service (QoS). Unfortunately, to provide this high QoS to the VBR video traffic with a high efficiency in bandwidth utilization is not a trivial problem. This is due to the bursty nature of the VBR video traffic on different time scales. This traffic behavior is named self-similarity. In order to improve channel utilization, some services with bandwidth renegotiation have been proposed. In this work, a new mechanism to accomplish bandwidth renegotiation over ATM networks for VBR video traffic is presented. The mechanism is based on a previous characterization of the MPEG VBR video traffic at the group of pictures (GoP) level by means of a bidimensional Markov modulated fluid process (MMFP). A new element, with supervision and control functions, is proposed and validated. Moreover, the achieved benefits in terms of the bandwidth gain that can be expected with the renegotiation system are analytically computed using the fluid flow approximation. Finally, the applicability of the supervisor and controller elements and its parameters are studied using four long MPEG VBR sequences
In this paper we propose an architecture to provide Quality of Service (QoS) guarantees for DVB-S... more 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 bandwi...
IFIP International Federation for Information Processing
Multimedia Communications and Video Coding, 1996
Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traf... more Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traffic coming from variable bit rate video (VBR) codecs1, which are capable of maintaining a constant picture quality of the decoded image. The characterization of such VBR video sources becomes important in the analysis and design of Broadband Integrated Services Digital Networks (B-ISDN). The network architecture and its characteristics, such as cell-loss probabilities, transmission delay, high-speed statistical multiplexing gain, buffering, etc., are strongly related to the statistical properties of the sources and the coding schemes involved.
Proceedings of ICC/SUPERCOMM '96 - International Conference on Communications
This paper presents an analysis of the aggregate traffic of variable bit rate (VBR) MPEG-1 source... more This paper presents an analysis of the aggregate traffic of variable bit rate (VBR) MPEG-1 sources. The aggregate traffic was implemented by the superposition of different copies of a real sample obtained at the output of an MPEG coder. These copies were offset a random time interval, that was not forced to be a multiple of the interframe time. The
Lecture Notes in Computer Science, 2009
2011 IEEE International Symposium on Industrial Electronics, 2011
Page 1. MODELADO SEMÁNTICO Y UBICUO DEL COMERCIO ELECTRÓNICO MEDIANTE WEB SER VICES Juan Carlos P... more Page 1. MODELADO SEMÁNTICO Y UBICUO DEL COMERCIO ELECTRÓNICO MEDIANTE WEB SER VICES Juan Carlos Peláez López, Jorge Mata Díaz Departamento de Ingeniería Telemática. Universitat Politf!Cnica de ...
Knowledge and Information Systems, 2014
One of the hardest tasks of a certification infrastructure is to manage revocation. This process ... more 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 on the trade-offs that different revocation mechanisms offer. Much less effort has been conducted to understand and model real-world revocation processes. For this reason, in this paper, we present a novel analysis of realworld collected revocation data and we propose a revocation prediction model. The model uses an Autoregressive Integrated Moving Average Model (ARIMA). Our prediction model enables certification authorities to forecast the percentage of revoked certificates.
ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN network... more ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN networks include the transmission of variable bit rate (VBR) video traffic. Generally, the nature of this kind of services implies the need of a high quality of service (QoS). Unfortunately, to provide this high QoS to the VBR video traffic with a high efficiency in bandwidth utilization is not a trivial problem. This is due to the bursty nature of the VBR video traffic on different time scales. This traffic behavior is named self-similarity. In order to improve channel utilization, some services with bandwidth renegotiation have been proposed. In this work, a new mechanism to accomplish bandwidth renegotiation over ATM networks for VBR video traffic is presented. The mechanism is based on a previous characterization of the MPEG VBR video traffic at the group of pictures (GoP) level by means of a bidimensional Markov modulated fluid process (MMFP). A new element, with supervision and control functions, is proposed and validated. Moreover, the achieved benefits in terms of the bandwidth gain that can be expected with the renegotiation system are analytically computed using the fluid flow approximation. Finally, the applicability of the supervisor and controller elements and its parameters are studied using four long MPEG VBR sequences
TDX (Tesis Doctorals en Xarxa), Nov 19, 1996
En esta tesis se trata el problema de integración de servicios en redes ATM. En particular, el tr... more En esta tesis se trata el problema de integración de servicios en redes ATM. En particular, el trabajo se centra en los servicios que incorporan información de vídeo digital.La tesis se compone en cinco capítulos. El primer capítulo presenta el escenario y la motivación en el que se enmarca este trabajo, introduciéndose las técnicas y conceptos empleados para su desarrollo. En los tres capítulos centrales se formulan los problemas actuales tratados en esta tesis y se discuten las soluciones planteadas y estandarizadas hasta el momento. Asimismo, se proponen nuevas maneras de abordar cada problemática presentando en cada caso una solución contrastada. Finalmente, en el último capítulo se enumeran las conclusiones obtenidas y se proponen nuevas líneas de investigación derivadas del presente estudio. El trabajo desarrollado puede estructurarse en tres fases asociadas con la presentación realizada en los tres capitulos centrales:i ) En el capítulo 2 se presentan las distintas técnicas e...
Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traf... more Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traffic coming from variable bit rate video (VBR) codecs1, which are capable of maintaining a constant picture quality of the decoded image. The characterization of such VBR video sources becomes important in the analysis and design of Broadband Integrated Services Digital Networks (B-ISDN). The network architecture and its characteristics, such as cell-loss probabilities, transmission delay, high-speed statistical multiplexing gain, buffering, etc., are strongly related to the statistical properties of the sources and the coding schemes involved. On the other hand, a characterization of the traffic generated by a VBR source is necessary in order to allocate resources in ATM networks, as well as, to keep a satisfactory quality of service (QoS). In the call establishment phase, service requirements are negotiated between the user and the network to establish a Traffic Contract. The source tra...
Fifth IEEE International Workshop on Computer-Aided Modeling, Analysis, and Design of Communication Links and Networks, 1994
First International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks
Seamless Interconnection for Universal Services. Global Telecommunications Conference. GLOBECOM'99. (Cat. No.99CH37042)
ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN network... more ABSTRACT Most of the new and interesting services that can be implemented over the B-ISDN networks include the transmission of variable bit rate (VBR) video traffic. Generally, the nature of this kind of services implies the need of a high quality of service (QoS). Unfortunately, to provide this high QoS to the VBR video traffic with a high efficiency in bandwidth utilization is not a trivial problem. This is due to the bursty nature of the VBR video traffic on different time scales. This traffic behavior is named self-similarity. In order to improve channel utilization, some services with bandwidth renegotiation have been proposed. In this work, a new mechanism to accomplish bandwidth renegotiation over ATM networks for VBR video traffic is presented. The mechanism is based on a previous characterization of the MPEG VBR video traffic at the group of pictures (GoP) level by means of a bidimensional Markov modulated fluid process (MMFP). A new element, with supervision and control functions, is proposed and validated. Moreover, the achieved benefits in terms of the bandwidth gain that can be expected with the renegotiation system are analytically computed using the fluid flow approximation. Finally, the applicability of the supervisor and controller elements and its parameters are studied using four long MPEG VBR sequences
In this paper we propose an architecture to provide Quality of Service (QoS) guarantees for DVB-S... more 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 bandwi...
IFIP International Federation for Information Processing
Multimedia Communications and Video Coding, 1996
Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traf... more Broadband Networks based on the Asynchronous Transfer Mode (ATM) will support, among others, traffic coming from variable bit rate video (VBR) codecs1, which are capable of maintaining a constant picture quality of the decoded image. The characterization of such VBR video sources becomes important in the analysis and design of Broadband Integrated Services Digital Networks (B-ISDN). The network architecture and its characteristics, such as cell-loss probabilities, transmission delay, high-speed statistical multiplexing gain, buffering, etc., are strongly related to the statistical properties of the sources and the coding schemes involved.
Proceedings of ICC/SUPERCOMM '96 - International Conference on Communications
This paper presents an analysis of the aggregate traffic of variable bit rate (VBR) MPEG-1 source... more This paper presents an analysis of the aggregate traffic of variable bit rate (VBR) MPEG-1 sources. The aggregate traffic was implemented by the superposition of different copies of a real sample obtained at the output of an MPEG coder. These copies were offset a random time interval, that was not forced to be a multiple of the interframe time. The
Lecture Notes in Computer Science, 2009
2011 IEEE International Symposium on Industrial Electronics, 2011
Page 1. MODELADO SEMÁNTICO Y UBICUO DEL COMERCIO ELECTRÓNICO MEDIANTE WEB SER VICES Juan Carlos P... more Page 1. MODELADO SEMÁNTICO Y UBICUO DEL COMERCIO ELECTRÓNICO MEDIANTE WEB SER VICES Juan Carlos Peláez López, Jorge Mata Díaz Departamento de Ingeniería Telemática. Universitat Politf!Cnica de ...
Knowledge and Information Systems, 2014
One of the hardest tasks of a certification infrastructure is to manage revocation. This process ... more 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 on the trade-offs that different revocation mechanisms offer. Much less effort has been conducted to understand and model real-world revocation processes. For this reason, in this paper, we present a novel analysis of realworld collected revocation data and we propose a revocation prediction model. The model uses an Autoregressive Integrated Moving Average Model (ARIMA). Our prediction model enables certification authorities to forecast the percentage of revoked certificates.