All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
2018 14th International Conference on Network and Service Management (CNSM), 2018
Many management actions for networking infrastructures require to simultaneously consider the sta... more Many management actions for networking infrastructures require to simultaneously consider the state of several network elements. This is particularly critical in the case of reconfigurable deployments, such as Virtual or Software-Defined Networks, to scale the affected equipment up and prevent performance bottlenecks. In this light, we present dPRISMA (distributed Passive Retrieval of Information, and Statistical Multipoint Analysis), a passive monitoring system intended to fit statistical models for network measurements and raise alarms in the case of extreme behaviors. As distinguishing features, dPRISMA relies on cost-effective multi-point network measurements, and is able to select a suitable parametric model optimizing the trade-off between fitting and complexity. Therefore, it can (i) correlate records collected from several vantage points and detect where performance issues are most likely to appear; (ii) adjust alarms in terms of the probability of events; and (iii) adapt it...
In this paper, we show that server load correlates with TCP SYN response time (SRT), that is, the... more In this paper, we show that server load correlates with TCP SYN response time (SRT), that is, the time from SYN to SYN+ACK segments at the server side. For this, it applies the innovative approach of modeling the SRT with an appropriate αstable heavy tail distribution. We also show that αstable distribution parameters are related to the server load the connection is attempted to. This approach provides a nonintrusive way to estimate the server load, and it can be useful to identify if a problem in a distributed application is caused by the end system, or to distribute the load among servers. Finally, based on obtained results, we propose a method that estimates server load based on SRT.
Homology detection has evolved over the time from heavy algorithms based on dynamic programming a... more Homology detection has evolved over the time from heavy algorithms based on dynamic programming approaches to lightweight alternatives based on different heuristic models. However, the main problem with these algorithms is that they use complex statistical models, which makes it difficult to achieve a relevant speedup and find exact matches with the original results. Thus, their acceleration is essential. The aim of this article was to prefilter a sequence database. To make this work, we have implemented a groundbreaking heuristic model based on NVIDIA's graphics processing units (GPUs) and multicore processors. Depending on the sensitivity settings, this makes it possible to quickly reduce the sequence database by factors between 50% and 95%, while rejecting no significant sequences. Furthermore, this prefiltering application can be used together with multiple homology detection algorithms as a part of a next-generation sequencing system. Extensive performance and accuracy test...
Advances in Intelligent Systems and Computing, 2014
Protein and DNA homology detection systems are an essential part in computational biology applica... more Protein and DNA homology detection systems are an essential part in computational biology applications. These algorithms have changed over the time from dynamic programming approaches by finding the optimal local alignment between two sequences to statistical approaches with different kinds of heuristics that minimize former executions times. However, the continuously increasing size of input datasets is being projected into the use of High Performance Computing (HPC) hardware and software in order to address this problem. The aim of the research presented in this paper is to propose a new filtering methodology, based on general-purpose graphical processor units (GP-GPUs) and multi-core processors, for removing those sequences considered irrelevant in terms of homology and similarity. The proposed methodology is completely independent from the homology detection algorithm. This approach is very useful for researchers and practitioners because they do not need to understand a new algorithm. This design has been approved by the National Biotechnology Research Center of Spain (CNB).
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Abstract—In Optical Burst Switched networks, when a Burst Control Packet arrives at a core node, ... more Abstract—In Optical Burst Switched networks, when a Burst Control Packet arrives at a core node, its scheduling algorithm looks up its internal reservation table for an available gap at which to accomodate the incoming burst. The processing time of the BCP is variable, and depends on the number of available gaps over which to perform the search. This work analyses the gap distribution in such reservation table, and derives an expression for the waiting time of BCPs, assuming LAUC-VF scheduling. Our findings can be applied to the dimensioning of the offset time values in OBS networks, for a realistic case of BCP variable processing times.
IEEE Transactions on Network and Service Management
Many network management actions need a simultaneous consideration of several elements’ state. Thi... more Many network management actions need a simultaneous consideration of several elements’ state. This is becoming an even more complex matter with the advent of reconfigurable deployments, where scaling functions up can prevent performance bottlenecks. Therefore, fine-grained detection of significant burdens arises as a cornerstone to optimize their monitoring and operation. We present advanced distributed passive retrieval of information, and statistical multi-point analysis (AdPRISMA), a passive monitoring system intended to fit models for network delay measurements with clustering elements to improve representation of central and extreme behaviors. As distinguishing features, it relies on cost-effective multi-point round-trip time (RTT) passive network measurements, and is able to select a suitable parametric model optimizing the trade-off between fitting and complexity. AdPRISMA can correlate records collected from several vantage points and detect where performance issues are most likely to appear; adjust alarms in terms of the probability of events; and adapt its behavior to dynamic network conditions while presenting a fair identification of anomalous situations. We evaluate AdPRISMA with experiments both in virtual environments and with real-world data to provide evidences of its applicability and capabilities to represent network elements’ delay.
Intelligent Robots and Computer Vision X: Neural, Biological, and 3-D Methods, 1992
ABSTRACT A new approach to identify the three-dimensional transformation is presented based in fo... more ABSTRACT A new approach to identify the three-dimensional transformation is presented based in four- dimensional tensor theory. It allows the isolation of the 3-D transformation parameters using data from real perspective projection of a rigid planar path object. With this approach there is no need of point correspondence between the image and the reference position of the object. It uses perspective projection modeling of the image and, thus there are no unresolved angles as in the case of parallel projection.
Proceedings of SPIE - The International Society for Optical Engineering
A new approach to identify the three-dimensional transformation is presented based in four- dimen... more A new approach to identify the three-dimensional transformation is presented based in four- dimensional tensor theory. It allows the isolation of the 3-D transformation parameters using data from real perspective projection of a rigid planar path object. With this approach there is no need of point correspondence between the image and the reference position of the object. It uses perspective projection modeling of the image and, thus there are no unresolved angles as in the case of parallel projection.
Pacific Rim TransTech Conference. 1995 Vehicle Navigation and Information Systems Conference Proceedings. 6th International VNIS. A Ride into the Future, 1995
ABSTRACT The author describes the CIT project which implements a traffic information center based... more ABSTRACT The author describes the CIT project which implements a traffic information center based on open systems technology. It integrates geographical, real-time and public services data and now offers driver information through a free phone call to any citizen. The key design points and issues of the project are explained in this paper
Aparato para la medicion certificada del ancho de banda de un acceso de red y metodo de calibraci... more Aparato para la medicion certificada del ancho de banda de un acceso de red y metodo de calibracion del mismo. El aparato permite calcular con exactitud el ancho de banda de una conexion de forma certificada, permitiendo posteriores reclamaciones en caso de necesidad. Comprende unos medios procesadores (1), asociados a una interfaz de red (2) a traves de la que se conecta al acceso a medir su ancho de banda, medios procesadores que cuentan con un software a partir del cual y por medio de la citada interfaz de red (2) se efectuan una serie de medidas reflejadas en la orden ministerial ITC/912/2006 relativas a la calidad de servicio en la prestacion de los servicios de comunicaciones electronicas, medidas que se almacenan en unos medios de almacenamiento (3). Los medios procesadores (1) estan asociados a un puerto serie (4) a traves del que se comunica con una fuente de reloj externa (6) calibrada y legalmente valida, que por medio de un contador de pulsos (7) permite efectuar su cali...
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
2018 14th International Conference on Network and Service Management (CNSM), 2018
Many management actions for networking infrastructures require to simultaneously consider the sta... more Many management actions for networking infrastructures require to simultaneously consider the state of several network elements. This is particularly critical in the case of reconfigurable deployments, such as Virtual or Software-Defined Networks, to scale the affected equipment up and prevent performance bottlenecks. In this light, we present dPRISMA (distributed Passive Retrieval of Information, and Statistical Multipoint Analysis), a passive monitoring system intended to fit statistical models for network measurements and raise alarms in the case of extreme behaviors. As distinguishing features, dPRISMA relies on cost-effective multi-point network measurements, and is able to select a suitable parametric model optimizing the trade-off between fitting and complexity. Therefore, it can (i) correlate records collected from several vantage points and detect where performance issues are most likely to appear; (ii) adjust alarms in terms of the probability of events; and (iii) adapt it...
In this paper, we show that server load correlates with TCP SYN response time (SRT), that is, the... more In this paper, we show that server load correlates with TCP SYN response time (SRT), that is, the time from SYN to SYN+ACK segments at the server side. For this, it applies the innovative approach of modeling the SRT with an appropriate αstable heavy tail distribution. We also show that αstable distribution parameters are related to the server load the connection is attempted to. This approach provides a nonintrusive way to estimate the server load, and it can be useful to identify if a problem in a distributed application is caused by the end system, or to distribute the load among servers. Finally, based on obtained results, we propose a method that estimates server load based on SRT.
Homology detection has evolved over the time from heavy algorithms based on dynamic programming a... more Homology detection has evolved over the time from heavy algorithms based on dynamic programming approaches to lightweight alternatives based on different heuristic models. However, the main problem with these algorithms is that they use complex statistical models, which makes it difficult to achieve a relevant speedup and find exact matches with the original results. Thus, their acceleration is essential. The aim of this article was to prefilter a sequence database. To make this work, we have implemented a groundbreaking heuristic model based on NVIDIA's graphics processing units (GPUs) and multicore processors. Depending on the sensitivity settings, this makes it possible to quickly reduce the sequence database by factors between 50% and 95%, while rejecting no significant sequences. Furthermore, this prefiltering application can be used together with multiple homology detection algorithms as a part of a next-generation sequencing system. Extensive performance and accuracy test...
Advances in Intelligent Systems and Computing, 2014
Protein and DNA homology detection systems are an essential part in computational biology applica... more Protein and DNA homology detection systems are an essential part in computational biology applications. These algorithms have changed over the time from dynamic programming approaches by finding the optimal local alignment between two sequences to statistical approaches with different kinds of heuristics that minimize former executions times. However, the continuously increasing size of input datasets is being projected into the use of High Performance Computing (HPC) hardware and software in order to address this problem. The aim of the research presented in this paper is to propose a new filtering methodology, based on general-purpose graphical processor units (GP-GPUs) and multi-core processors, for removing those sequences considered irrelevant in terms of homology and similarity. The proposed methodology is completely independent from the homology detection algorithm. This approach is very useful for researchers and practitioners because they do not need to understand a new algorithm. This design has been approved by the National Biotechnology Research Center of Spain (CNB).
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Abstract—In Optical Burst Switched networks, when a Burst Control Packet arrives at a core node, ... more Abstract—In Optical Burst Switched networks, when a Burst Control Packet arrives at a core node, its scheduling algorithm looks up its internal reservation table for an available gap at which to accomodate the incoming burst. The processing time of the BCP is variable, and depends on the number of available gaps over which to perform the search. This work analyses the gap distribution in such reservation table, and derives an expression for the waiting time of BCPs, assuming LAUC-VF scheduling. Our findings can be applied to the dimensioning of the offset time values in OBS networks, for a realistic case of BCP variable processing times.
IEEE Transactions on Network and Service Management
Many network management actions need a simultaneous consideration of several elements’ state. Thi... more Many network management actions need a simultaneous consideration of several elements’ state. This is becoming an even more complex matter with the advent of reconfigurable deployments, where scaling functions up can prevent performance bottlenecks. Therefore, fine-grained detection of significant burdens arises as a cornerstone to optimize their monitoring and operation. We present advanced distributed passive retrieval of information, and statistical multi-point analysis (AdPRISMA), a passive monitoring system intended to fit models for network delay measurements with clustering elements to improve representation of central and extreme behaviors. As distinguishing features, it relies on cost-effective multi-point round-trip time (RTT) passive network measurements, and is able to select a suitable parametric model optimizing the trade-off between fitting and complexity. AdPRISMA can correlate records collected from several vantage points and detect where performance issues are most likely to appear; adjust alarms in terms of the probability of events; and adapt its behavior to dynamic network conditions while presenting a fair identification of anomalous situations. We evaluate AdPRISMA with experiments both in virtual environments and with real-world data to provide evidences of its applicability and capabilities to represent network elements’ delay.
Intelligent Robots and Computer Vision X: Neural, Biological, and 3-D Methods, 1992
ABSTRACT A new approach to identify the three-dimensional transformation is presented based in fo... more ABSTRACT A new approach to identify the three-dimensional transformation is presented based in four- dimensional tensor theory. It allows the isolation of the 3-D transformation parameters using data from real perspective projection of a rigid planar path object. With this approach there is no need of point correspondence between the image and the reference position of the object. It uses perspective projection modeling of the image and, thus there are no unresolved angles as in the case of parallel projection.
Proceedings of SPIE - The International Society for Optical Engineering
A new approach to identify the three-dimensional transformation is presented based in four- dimen... more A new approach to identify the three-dimensional transformation is presented based in four- dimensional tensor theory. It allows the isolation of the 3-D transformation parameters using data from real perspective projection of a rigid planar path object. With this approach there is no need of point correspondence between the image and the reference position of the object. It uses perspective projection modeling of the image and, thus there are no unresolved angles as in the case of parallel projection.
Pacific Rim TransTech Conference. 1995 Vehicle Navigation and Information Systems Conference Proceedings. 6th International VNIS. A Ride into the Future, 1995
ABSTRACT The author describes the CIT project which implements a traffic information center based... more ABSTRACT The author describes the CIT project which implements a traffic information center based on open systems technology. It integrates geographical, real-time and public services data and now offers driver information through a free phone call to any citizen. The key design points and issues of the project are explained in this paper
Aparato para la medicion certificada del ancho de banda de un acceso de red y metodo de calibraci... more Aparato para la medicion certificada del ancho de banda de un acceso de red y metodo de calibracion del mismo. El aparato permite calcular con exactitud el ancho de banda de una conexion de forma certificada, permitiendo posteriores reclamaciones en caso de necesidad. Comprende unos medios procesadores (1), asociados a una interfaz de red (2) a traves de la que se conecta al acceso a medir su ancho de banda, medios procesadores que cuentan con un software a partir del cual y por medio de la citada interfaz de red (2) se efectuan una serie de medidas reflejadas en la orden ministerial ITC/912/2006 relativas a la calidad de servicio en la prestacion de los servicios de comunicaciones electronicas, medidas que se almacenan en unos medios de almacenamiento (3). Los medios procesadores (1) estan asociados a un puerto serie (4) a traves del que se comunica con una fuente de reloj externa (6) calibrada y legalmente valida, que por medio de un contador de pulsos (7) permite efectuar su cali...
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