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Genaro Hernandez-valdez - One of the best experts on this subject based on the ideXlab platform.

  • Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic
    2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, the relevance of considering the primary network resource occupancy information on the Admission Criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call Admission control (CAC) strategies whose Admission Criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.

  • CrownCom - Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic
    Proceedings of the 7th International Conference on Cognitive Radio Oriented Wireless Networks, 2012
    Co-Authors: S. Lirio Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, the relevance of considering the primary network resource occupancy information on the Admission Criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call Admission control (CAC) strategies whose Admission Criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.

  • Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks
    2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call Admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The Admission Criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.

  • WCNC - Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks
    2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012
    Co-Authors: S. Lirio Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call Admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The Admission Criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.

  • GLOBECOM - Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless
    2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
    Co-Authors: S. Lirio Castellanos-lopez, Genaro Hernandez-valdez, Mario E. Rivero-angeles, Felipe A. Cruz-pérez
    Abstract:

    Call Admission control (CAC) functionality is a critical requirement for guarantee the desired quality of service (QoS) for voice calls in IP-based wireless networks. In this paper, three different CAC strategies for voice over IP (VoIP) traffic over wireless access networks with packet buffering are mathematically analyzed through a joint call and packet level discrete time teletraffic model. The Admission Criterion (i.e., Admission threshold) of new sessions of these strategies is based on either the total number of sessions, the number of active sessions (i.e., sessions in talk-spurt periods), or the number of packets queued in the buffer. Admission threshold and buffer size can be both controlled for QoS provisioning in terms of session blocking and packet dropping probabilities. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation (of active sessions) of individual VoIP sessions are modeled. The developed teletraffic analysis allows to evaluate the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level (i.e., session blocking and packet dropping probabilities and packet delay). Finally, the maximum traffic attained by the different studied-CAC strategies (while QoS provisioning is guaranteed) is obtained.

Felipe A. Cruz-pérez - One of the best experts on this subject based on the ideXlab platform.

  • Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic
    2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, the relevance of considering the primary network resource occupancy information on the Admission Criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call Admission control (CAC) strategies whose Admission Criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.

  • CrownCom - Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic
    Proceedings of the 7th International Conference on Cognitive Radio Oriented Wireless Networks, 2012
    Co-Authors: S. Lirio Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, the relevance of considering the primary network resource occupancy information on the Admission Criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call Admission control (CAC) strategies whose Admission Criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.

  • Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks
    2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call Admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The Admission Criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.

  • WCNC - Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks
    2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012
    Co-Authors: S. Lirio Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call Admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The Admission Criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.

  • GLOBECOM - Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless
    2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
    Co-Authors: S. Lirio Castellanos-lopez, Genaro Hernandez-valdez, Mario E. Rivero-angeles, Felipe A. Cruz-pérez
    Abstract:

    Call Admission control (CAC) functionality is a critical requirement for guarantee the desired quality of service (QoS) for voice calls in IP-based wireless networks. In this paper, three different CAC strategies for voice over IP (VoIP) traffic over wireless access networks with packet buffering are mathematically analyzed through a joint call and packet level discrete time teletraffic model. The Admission Criterion (i.e., Admission threshold) of new sessions of these strategies is based on either the total number of sessions, the number of active sessions (i.e., sessions in talk-spurt periods), or the number of packets queued in the buffer. Admission threshold and buffer size can be both controlled for QoS provisioning in terms of session blocking and packet dropping probabilities. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation (of active sessions) of individual VoIP sessions are modeled. The developed teletraffic analysis allows to evaluate the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level (i.e., session blocking and packet dropping probabilities and packet delay). Finally, the maximum traffic attained by the different studied-CAC strategies (while QoS provisioning is guaranteed) is obtained.

Lirio S. Castellanos-lopez - One of the best experts on this subject based on the ideXlab platform.

  • Impact of the primary resource occupancy information on the performance of cognitive radio networks with VoIP traffic
    2012 7th International ICST Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, the relevance of considering the primary network resource occupancy information on the Admission Criterion of new secondary VoIP sessions in cognitive radio networks (CRNs) is investigated. In particular, the performance of two different call Admission control (CAC) strategies whose Admission Criterion is based either on the total number of primary and secondary sessions or only on the number of sessions of secondary users is compared. System performance is evaluated in terms of the most relevant quality of service metrics for VoIP traffic at both call and packet level. Numerical results clearly show that including primary resource occupancy information on the CAC strategy is an effective mean to improve system performance, especially for low to moderate traffic loads. For instance, assuming that voice toll quality is required, packet dropping probability is reduced more than 30% when primary resource occupancy information is additionally used on the CAC strategy.

  • Simplified joint call and packet level teletraffic analysis of CAC strategies for VoIP traffic in wireless networks
    2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012
    Co-Authors: Lirio S. Castellanos-lopez, Felipe A. Cruz-pérez, Mario E. Rivero-angeles, Genaro Hernandez-valdez
    Abstract:

    In this paper, a simplified joint call and packet level teletraffic analysis method for performance evaluation of call Admission control (CAC) strategies for voice over IP (VoIP) traffic over wireless access networks is proposed. The Admission Criterion of new sessions of the considered CAC strategies is based on either the total number of sessions or the number of active sessions. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation of individual VoIP active sessions are modeled. Packet buffering, adaptive modulation coding, and proportional fair sharing scheduling are also considered. Our proposed analysis is based on the quantized queue and cross-level linked decomposition mechanisms that we introduce in this paper to drastically simplify the mathematical and computational procedures with no major impact on the accuracy of the results. The developed analysis allows evaluating the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level and, at the same time, mathematical and computational complexity are reduced with no major impact on the accuracy of numerical results.

  • Joint Call and Packet Level Performance Analysis of CAC Strategies for VoIP Traffic in Wireless
    2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
    Co-Authors: Lirio S. Castellanos-lopez, Mario E. Rivero-angeles, Genaro Hernandez-valdez, Felipe A. Cruz-pérez
    Abstract:

    Call Admission control (CAC) functionality is a critical requirement for guarantee the desired quality of service (QoS) for voice calls in IP-based wireless networks. In this paper, three different CAC strategies for voice over IP (VoIP) traffic over wireless access networks with packet buffering are mathematically analyzed through a joint call and packet level discrete time teletraffic model. The Admission Criterion (i.e., Admission threshold) of new sessions of these strategies is based on either the total number of sessions, the number of active sessions (i.e., sessions in talk-spurt periods), or the number of packets queued in the buffer. Admission threshold and buffer size can be both controlled for QoS provisioning in terms of session blocking and packet dropping probabilities. Arrivals and completions of VoIP sessions, on/off activity detection, and periodic and constant length packet generation (of active sessions) of individual VoIP sessions are modeled. The developed teletraffic analysis allows to evaluate the performance of the CAC strategies in terms of the most relevant QoS metrics of VoIP traffic at both call and packet level (i.e., session blocking and packet dropping probabilities and packet delay). Finally, the maximum traffic attained by the different studied-CAC strategies (while QoS provisioning is guaranteed) is obtained.

Sheila Isanaka - One of the best experts on this subject based on the ideXlab platform.

  • comparison of weight for height and mid upper arm circumference muac in a therapeutic feeding programme in south sudan is muac alone a sufficient Criterion for Admission of children at high risk of mortality
    Public Health Nutrition, 2015
    Co-Authors: Emmanuel Grellety, Kendall L Krause, Manal Shams Eldin, Klaudia Porten, Sheila Isanaka
    Abstract:

    Objective The present study was performed to describe the operational implications of using mid-upper arm circumference (MUAC) as a single Admission Criterion for treatment of severe acute malnutrition in South Sudan. Design We performed a retrospective analysis of routine programme data of children with severe acute malnutrition aged 6–59 months admitted to a therapeutic feeding programme using weight-for-height Z -score (WHZ) and/or MUAC. To understand the implications of using MUAC as a single Admission Criterion, we compared patient characteristics and treatment outcomes for children admitted with MUAC v . children admitted with WHZ Results Of 2205 children included for analysis, 719 (32·6 %) were admitted to the programme with MUAC v . 69 %) and had higher risk of death (4 % v . 1 %), but responded to treatment with greater weight and MUAC gains. MUAC Conclusions The study shows that MUAC

  • Comparison of Clinical Characteristics and Treatment Outcomes of Children Selected for Treatment of Severe Acute Malnutrition Using Mid Upper Arm Circumference and/or Weight-for-Height Z-Score
    PLOS ONE, 2015
    Co-Authors: Sheila Isanaka, Benjamin Guesdon, Amy S. Labar, Kerstin Hanson, Céline Langendorf, Rebecca F. Grais
    Abstract:

    Objectives Debate for a greater role of mid-upper arm circumference (MUAC) measures in nutritional programming continues, but a shift from therapeutic feeding programs admitting children using MUAC and/or weight-for-height Z (WHZ) to a new model admitting children using MUAC only remains complicated by limited information regarding the clinical profile and response to treatment of children selected by MUAC vs. WHZ. To broaden our understanding of how children identified for therapeutic feeding by MUAC and/or WHZ may differ, we aimed to investigate differences between children identified for therapeutic feeding by MUAC and/or WHZ in terms of demographic, anthropometric, clinical, and laboratory and treatment response characteristics. Methods Using secondary data from a randomized trial in rural Niger among children with uncomplicated severe acute malnutrition, we compared children that would be admitted to a therapeutic feeding program that used a single anthropometric Criterion of MUAC< 115 mm vs. children that are admitted under current Admission criteria (WHZ< -3 and/or MUAC< 115 mm) but would be excluded from a program that used a single MUAC< 115 mm Admission Criterion. We assessed differences between groups using multivariate regression, employing linear regression for continuous outcomes and log-binomial regression for dichotomous outcomes. Results We found no difference in terms of clinical and laboratory characteristics and discharge outcomes evaluated between children that would be included in a MUAC< 115 mm therapeutic feeding program vs. children that are currently eligible for therapeutic feeding but would be excluded from a MUAC-only program. Conclusions A single anthropometric Admission Criterion of MUAC < 115 mm did not differentiate well between children in terms of clinical or laboratory measures or program outcomes in this context. If nutritional programming is to use a single MUAC-based Criterion for Admission to treatment, further research and program experience can help to identify the most appropriate Criterion in a broad range of contexts to target children in most urgent need of treatment.

D. Mitra - One of the best experts on this subject based on the ideXlab platform.

  • EFFECTIVE BANDWIDTH OF GENERAL MARKOVIAN TRAFFIC SOURCES AND Admission CONTROL OF HIGH SPEED NETWORKS (Extended Abstract)
    1993
    Co-Authors: A.i. Elwalid, D. Mitra, Murray Hill
    Abstract:

    The emerging high speed networks, notably the ATMbased Broadband-ISDN, are expected to integrate through statistical multiplexing large numbers of traflc sources having a broad range of burstiness characteristics. A prime instrument for controlling congestion in the network is Admission control which limits calls and guarantees a grade of service determined by delay and loss probability in the multiplexel: We show, for general Markovian trafJic sources, that it is possible to assign a notional effective bandwidth to each source which is an explicitly identijied, simply computed quantity with provably correct properties in the natural asymptotic regime of small loss probabilities. It is the maximal real eigenvalue of a matrix which is directly obtained from the source characteristics and the Admission Criterion, and for several sources it is simply additive. We consider both fluid and point process models and obtain parallel results. Numerical results show that the acceptance set for heterogeneous classes of sources is closely approximated and conservatively bounded by the set obtained from the effective bandwidth approximation.

  • Effective bandwidth of bursty, variable rate sources for Admission control to B-ISDN
    Proceedings of ICC '93 - IEEE International Conference on Communications, 1993
    Co-Authors: A.i. Elwalid, D. Mitra
    Abstract:

    A prime instrument for controlling congestion in the broadband integrated services digital network (B-ISDN) is Admission control. It is shown that for the Admission control of general Markovian traffic sources, it is possible to assign a notional effective bandwidth to each source which is an explicitly identified, simply computed quantity with provably correct properties in the natural asymptotic regime of small loss probabilities. It is the maximal real eigenvalue of a matrix which is directly obtained from the source characteristics and the Admission Criterion, and, for several sources, it is simply additive. Both fluid and point process models are considered, and parallel results are obtained. The effective-bandwidth reducing properties of the leaky bucket regulator are reported, and the leaky bucket parameters are related to the buffer requirements at the multiplexer.

  • INFOCOM - Effective bandwidth of general Markovian traffic sources and Admission control of high speed networks
    IEEE INFOCOM '93 The Conference on Computer Communications Proceedings, 1993
    Co-Authors: A.i. Elwalid, D. Mitra
    Abstract:

    A prime instrument for controlling congestion in high-speed broadband ISDN (BISDN) networks is Admission control, which limits call and guarantees a grade of service determined by delay and loss probability in the multiplexer. It is shown, for general Markovian traffic sources, that it is possible to assign a notational effective bandwidth to each source which is an explicitly identified, simply computing quantity with provably correct properties in the natural asymptotic regime of small loss probabilities. It is the maximal real eigenvalue of a matrix which is directly obtained from the source characteristics and the Admission Criterion, and for several sources it is simply additive. Both fluid and point process models are considered, and parallel results are obtained. Numerical results show that the acceptance set for heterogeneous classes of sources is closely approximated and conservatively bounded by the set obtained from the effective bandwidth approximation. >

  • Effective bandwidth of general Markovian traffic sources and Admission control of high speed networks
    IEEE INFOCOM '93 The Conference on Computer Communications Proceedings, 1993
    Co-Authors: A.i. Elwalid, D. Mitra
    Abstract:

    A prime instrument for controlling congestion in high-speed broadband ISDN (BISDN) networks is Admission control, which limits call and guarantees a grade of service determined by delay and loss probability in the multiplexer. It is shown, for general Markovian traffic sources, that it is possible to assign a notational effective bandwidth to each source which is an explicitly identified, simply computing quantity with provably correct properties in the natural asymptotic regime of small loss probabilities. It is the maximal real eigenvalue of a matrix which is directly obtained from the source characteristics and the Admission Criterion, and for several sources it is simply additive. Both fluid and point process models are considered, and parallel results are obtained. Numerical results show that the acceptance set for heterogeneous classes of sources is closely approximated and conservatively bounded by the set obtained from the effective bandwidth approximation.

  • Effective bandwidth of general Markovian traffic sources and Admission control of high speed networks
    IEEE ACM Transactions on Networking, 1993
    Co-Authors: A.i. Elwalid, D. Mitra
    Abstract:

    A prime instrument for controlling congestion in a high-speed network is Admission control, which limits calls and guarantees a grade of service determined by delay and loss probability in the multiplexer. It is shown that for general Markovian traffic sources it is possible to assign a notional effective bandwidth to each source that is an explicitly identified, simply computed quantity with provably correct properties in the natural asymptotic regime of small loss probabilities. It is the maximal real eigenvalue of a matrix that is directly obtained from the source characteristics and the Admission Criterion, and for several sources it is simply additive. Both fluid and point process models are considered. Numerical results show that the acceptance set for heterogeneous classes of sources is closely approximated and conservatively bounded by the set obtained from the effective bandwidth approximation. The bandwidth-reducing properties of the leaky bucket regulator are exhibited numerically.