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Ender Ayanoglu - One of the best experts on this subject based on the ideXlab platform.

  • Fair and efficient Transmission Control Protocol access in the IEEE 802.11 infrastructure basic service set
    Wireless Communications and Mobile Computing, 2013
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set employ Transmission Control Protocol TCP, this exacerbates per-flow unfair access problem. We propose a novel analytical model to approximately calculate the maximum per-flow TCP congestion window limit that prevents packet losses at the access point buffer and therefore provides fair TCP access both in the downlink and uplink. The proposed analysis is unique in considering the effects of varying number of uplink and downlink TCP flows, differing round trip times among TCP connections and the use of delayed TCP acknowledgment ACK mechanism. Motivated by the findings of this theoretical analysis and simulations, we design a link layer access control block to be employed only at the access point in order to resolve the unfair access problem. The proposed link layer access control block uses congestion control and ACK filtering approach by prioritizing the access of TCP data packets of downlink flows over TCP ACK packets of uplink flows. Via simulations, we show that the proposed algorithm can provide both short-term and long-term fair accesses while improving channel utilization and access delay. Copyright © 2013 John Wiley & Sons, Ltd.

  • A capacity analysis framework for the IEEE 802.11e contention-based infrastructure basic service set
    IEEE Transactions on Communications, 2009
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a multimedia capacity analysis framework for the Enhanced Distributed Channel Access (EDCA) function of the IEEE 802.11e standard. Our analysis shows that the multimedia capacity of the EDCA function for each Access Category (AC) can accurately be estimated by appropriately weighing the service time predictions of a saturation model over different number of active stations. We propose a simple and generic cycle time model to derive the service time in saturation which we employ in the calculation of an accurate station- and AC-specific queue utilization ratio. Based on the estimated queue utilization ratio, we design a simple model-based admission control scheme. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over-or under-admission problems of previously proposed models in the literature.

  • multimedia capacity analysis of the ieee 802 11e contention based infrastructure basic service set
    Global Communications Conference, 2008
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a novel and simple multimedia capacity analysis framework for the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) function. We design a simple model- based admission control scheme which is based on the accurate queue utilization ratio we calculate by appropriately weighing the service time predictions of our previously developed saturation cycle time model for different number of active stations. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over- or under-admission problems of previously proposed models in the literature.

  • Fair Access Provisioning through Contention Parameter Adaptation in the IEEE 802.11e Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    We present the station-based unfair access problem among the uplink and the downlink stations in the IEEE 802.11e infrastructure basic service set (BSS) when the default settings of the Enhanced Distributed Channel Access (EDCA) parameters are used. We discuss how the transport layer protocol characteristics alleviate the unfairness problem. We design a simple, practical, and standard-compliant framework to be employed at the Access Point (AP) for fair and efficient access provisioning. A dynamic measurement-based EDCA parameter adaptation block lies in the core of this framework. The proposed framework is unique in the sense that it considers the characteristic differences of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) flows and the coexistence of stations with varying bandwidth or Quality-of-service (QoS) requirements. Via simulations, we show that our solution provides short- and long-term fair access for all stations in the uplink and downlink employing TCP and UDP flows with non-uniform packet rates in a wired-wireless heterogeneous network. In the meantime, the QoS requirements of coexisting real-time flows are also maintained.

  • Fair and Efficient TCP Access in the IEEE 802.11 Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set (BSS) employ Transmission Control Protocol (TCP) in the transport layer, this exacerbates per-flow unfair access which is a direct result of uplink/downlink bandwidth asymmetry in the BSS. We propose a novel and simple analytical model to approximately calculate the per-flow TCP congestion window limit that provides fair and efficient TCP access in a heterogeneous wired-wireless scenario. The proposed analysis is unique in that it considers the effects of varying number of uplink and downlink TCP flows, differing Round Trip Times (RTTs) among TCP connections, and the use of delayed TCP Acknowledgment (ACK) mechanism. Motivated by the findings of this analysis, we design a link layer access control block to be employed only at the Access Point (AP) in order to resolve the unfair access problem. The novel and simple idea of the proposed link layer access control block is employing a congestion control and filtering algorithm on TCP ACK packets of uplink flows, thereby prioritizing the access of TCP data packets of downlink flows at the AP. Via simulations, we show that short- and long-term fair access can be provisioned with the introduction of the proposed link layer access control block to the protocol stack of the AP while improving channel utilization and access delay.

F. Keceli - One of the best experts on this subject based on the ideXlab platform.

  • Fair and efficient Transmission Control Protocol access in the IEEE 802.11 infrastructure basic service set
    Wireless Communications and Mobile Computing, 2013
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set employ Transmission Control Protocol TCP, this exacerbates per-flow unfair access problem. We propose a novel analytical model to approximately calculate the maximum per-flow TCP congestion window limit that prevents packet losses at the access point buffer and therefore provides fair TCP access both in the downlink and uplink. The proposed analysis is unique in considering the effects of varying number of uplink and downlink TCP flows, differing round trip times among TCP connections and the use of delayed TCP acknowledgment ACK mechanism. Motivated by the findings of this theoretical analysis and simulations, we design a link layer access control block to be employed only at the access point in order to resolve the unfair access problem. The proposed link layer access control block uses congestion control and ACK filtering approach by prioritizing the access of TCP data packets of downlink flows over TCP ACK packets of uplink flows. Via simulations, we show that the proposed algorithm can provide both short-term and long-term fair accesses while improving channel utilization and access delay. Copyright © 2013 John Wiley & Sons, Ltd.

  • A capacity analysis framework for the IEEE 802.11e contention-based infrastructure basic service set
    IEEE Transactions on Communications, 2009
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a multimedia capacity analysis framework for the Enhanced Distributed Channel Access (EDCA) function of the IEEE 802.11e standard. Our analysis shows that the multimedia capacity of the EDCA function for each Access Category (AC) can accurately be estimated by appropriately weighing the service time predictions of a saturation model over different number of active stations. We propose a simple and generic cycle time model to derive the service time in saturation which we employ in the calculation of an accurate station- and AC-specific queue utilization ratio. Based on the estimated queue utilization ratio, we design a simple model-based admission control scheme. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over-or under-admission problems of previously proposed models in the literature.

  • multimedia capacity analysis of the ieee 802 11e contention based infrastructure basic service set
    Global Communications Conference, 2008
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a novel and simple multimedia capacity analysis framework for the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) function. We design a simple model- based admission control scheme which is based on the accurate queue utilization ratio we calculate by appropriately weighing the service time predictions of our previously developed saturation cycle time model for different number of active stations. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over- or under-admission problems of previously proposed models in the literature.

  • Fair Access Provisioning through Contention Parameter Adaptation in the IEEE 802.11e Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    We present the station-based unfair access problem among the uplink and the downlink stations in the IEEE 802.11e infrastructure basic service set (BSS) when the default settings of the Enhanced Distributed Channel Access (EDCA) parameters are used. We discuss how the transport layer protocol characteristics alleviate the unfairness problem. We design a simple, practical, and standard-compliant framework to be employed at the Access Point (AP) for fair and efficient access provisioning. A dynamic measurement-based EDCA parameter adaptation block lies in the core of this framework. The proposed framework is unique in the sense that it considers the characteristic differences of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) flows and the coexistence of stations with varying bandwidth or Quality-of-service (QoS) requirements. Via simulations, we show that our solution provides short- and long-term fair access for all stations in the uplink and downlink employing TCP and UDP flows with non-uniform packet rates in a wired-wireless heterogeneous network. In the meantime, the QoS requirements of coexisting real-time flows are also maintained.

  • Fair and Efficient TCP Access in the IEEE 802.11 Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set (BSS) employ Transmission Control Protocol (TCP) in the transport layer, this exacerbates per-flow unfair access which is a direct result of uplink/downlink bandwidth asymmetry in the BSS. We propose a novel and simple analytical model to approximately calculate the per-flow TCP congestion window limit that provides fair and efficient TCP access in a heterogeneous wired-wireless scenario. The proposed analysis is unique in that it considers the effects of varying number of uplink and downlink TCP flows, differing Round Trip Times (RTTs) among TCP connections, and the use of delayed TCP Acknowledgment (ACK) mechanism. Motivated by the findings of this analysis, we design a link layer access control block to be employed only at the Access Point (AP) in order to resolve the unfair access problem. The novel and simple idea of the proposed link layer access control block is employing a congestion control and filtering algorithm on TCP ACK packets of uplink flows, thereby prioritizing the access of TCP data packets of downlink flows at the AP. Via simulations, we show that short- and long-term fair access can be provisioned with the introduction of the proposed link layer access control block to the protocol stack of the AP while improving channel utilization and access delay.

I. Inan - One of the best experts on this subject based on the ideXlab platform.

  • Fair and efficient Transmission Control Protocol access in the IEEE 802.11 infrastructure basic service set
    Wireless Communications and Mobile Computing, 2013
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set employ Transmission Control Protocol TCP, this exacerbates per-flow unfair access problem. We propose a novel analytical model to approximately calculate the maximum per-flow TCP congestion window limit that prevents packet losses at the access point buffer and therefore provides fair TCP access both in the downlink and uplink. The proposed analysis is unique in considering the effects of varying number of uplink and downlink TCP flows, differing round trip times among TCP connections and the use of delayed TCP acknowledgment ACK mechanism. Motivated by the findings of this theoretical analysis and simulations, we design a link layer access control block to be employed only at the access point in order to resolve the unfair access problem. The proposed link layer access control block uses congestion control and ACK filtering approach by prioritizing the access of TCP data packets of downlink flows over TCP ACK packets of uplink flows. Via simulations, we show that the proposed algorithm can provide both short-term and long-term fair accesses while improving channel utilization and access delay. Copyright © 2013 John Wiley & Sons, Ltd.

  • A capacity analysis framework for the IEEE 802.11e contention-based infrastructure basic service set
    IEEE Transactions on Communications, 2009
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a multimedia capacity analysis framework for the Enhanced Distributed Channel Access (EDCA) function of the IEEE 802.11e standard. Our analysis shows that the multimedia capacity of the EDCA function for each Access Category (AC) can accurately be estimated by appropriately weighing the service time predictions of a saturation model over different number of active stations. We propose a simple and generic cycle time model to derive the service time in saturation which we employ in the calculation of an accurate station- and AC-specific queue utilization ratio. Based on the estimated queue utilization ratio, we design a simple model-based admission control scheme. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over-or under-admission problems of previously proposed models in the literature.

  • multimedia capacity analysis of the ieee 802 11e contention based infrastructure basic service set
    Global Communications Conference, 2008
    Co-Authors: I. Inan, F. Keceli, Ender Ayanoglu
    Abstract:

    We propose a novel and simple multimedia capacity analysis framework for the IEEE 802.11e Enhanced Distributed Channel Access (EDCA) function. We design a simple model- based admission control scheme which is based on the accurate queue utilization ratio we calculate by appropriately weighing the service time predictions of our previously developed saturation cycle time model for different number of active stations. We show that the proposed call admission control algorithm maintains satisfactory user-perceived quality for coexisting voice and video connections in an infrastructure basic service set (BSS) and does not present over- or under-admission problems of previously proposed models in the literature.

  • Fair Access Provisioning through Contention Parameter Adaptation in the IEEE 802.11e Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    We present the station-based unfair access problem among the uplink and the downlink stations in the IEEE 802.11e infrastructure basic service set (BSS) when the default settings of the Enhanced Distributed Channel Access (EDCA) parameters are used. We discuss how the transport layer protocol characteristics alleviate the unfairness problem. We design a simple, practical, and standard-compliant framework to be employed at the Access Point (AP) for fair and efficient access provisioning. A dynamic measurement-based EDCA parameter adaptation block lies in the core of this framework. The proposed framework is unique in the sense that it considers the characteristic differences of Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) flows and the coexistence of stations with varying bandwidth or Quality-of-service (QoS) requirements. Via simulations, we show that our solution provides short- and long-term fair access for all stations in the uplink and downlink employing TCP and UDP flows with non-uniform packet rates in a wired-wireless heterogeneous network. In the meantime, the QoS requirements of coexisting real-time flows are also maintained.

  • Fair and Efficient TCP Access in the IEEE 802.11 Infrastructure basic service set
    arXiv: Networking and Internet Architecture, 2008
    Co-Authors: F. Keceli, I. Inan, Ender Ayanoglu
    Abstract:

    When the stations in an IEEE 802.11 infrastructure basic service set (BSS) employ Transmission Control Protocol (TCP) in the transport layer, this exacerbates per-flow unfair access which is a direct result of uplink/downlink bandwidth asymmetry in the BSS. We propose a novel and simple analytical model to approximately calculate the per-flow TCP congestion window limit that provides fair and efficient TCP access in a heterogeneous wired-wireless scenario. The proposed analysis is unique in that it considers the effects of varying number of uplink and downlink TCP flows, differing Round Trip Times (RTTs) among TCP connections, and the use of delayed TCP Acknowledgment (ACK) mechanism. Motivated by the findings of this analysis, we design a link layer access control block to be employed only at the Access Point (AP) in order to resolve the unfair access problem. The novel and simple idea of the proposed link layer access control block is employing a congestion control and filtering algorithm on TCP ACK packets of uplink flows, thereby prioritizing the access of TCP data packets of downlink flows at the AP. Via simulations, we show that short- and long-term fair access can be provisioned with the introduction of the proposed link layer access control block to the protocol stack of the AP while improving channel utilization and access delay.

Henry L Owen - One of the best experts on this subject based on the ideXlab platform.

  • wireless intrusion detection and response a classic study using main in the middle attack
    Wireless Communications and Networking Conference, 2004
    Co-Authors: T R Schmoyer, Yu Xi Lim, Henry L Owen
    Abstract:

    Intrusion detection and countermeasures response is an active area of research. In this paper, we examine integrating an intrusion detection engine with an active countermeasure capability. We use a classic man in the middle attack as a case study to specify the integrated wireless intrusion detection capability with the active countermeasure response. We present a case study in dynamically defending against an example attack in an 802.11 infrastructure basic service set by combining the concepts for a distributed wireless intrusion detection and response system architecture with adaptive response strategies based on alarm confidence, attack frequency, assessed risks, and estimated response costs. We also include a description of a tool kit we have implemented to prototypically test and evaluate our concepts.

  • WCNC - Wireless intrusion detection and response: a classic study using main-in-the-middle attack
    2004 IEEE Wireless Communications and Networking Conference (IEEE Cat. No.04TH8733), 1
    Co-Authors: T R Schmoyer, Yu Xi Lim, Henry L Owen
    Abstract:

    Intrusion detection and countermeasures response is an active area of research. In this paper, we examine integrating an intrusion detection engine with an active countermeasure capability. We use a classic man in the middle attack as a case study to specify the integrated wireless intrusion detection capability with the active countermeasure response. We present a case study in dynamically defending against an example attack in an 802.11 infrastructure basic service set by combining the concepts for a distributed wireless intrusion detection and response system architecture with adaptive response strategies based on alarm confidence, attack frequency, assessed risks, and estimated response costs. We also include a description of a tool kit we have implemented to prototypically test and evaluate our concepts.

Depeng Jin - One of the best experts on this subject based on the ideXlab platform.

  • MobiCom - Poster: promoting the spatial reuse of millimeter wave networks via software-defined cross-layer design
    Proceedings of the 20th annual international conference on Mobile computing and networking, 2014
    Co-Authors: Yong Niu, Depeng Jin
    Abstract:

    Recently, millimeter wave communications in 60 GHz band have attracted considerable attention from academia, industry, and standards bodies. To overcome huge propagation loss, high gain directional antennas are used. Consequently, concurrent transmissions (spatial reuse) are enabled within a basic service set (BSS) and even among BSSs, which provides huge potential to improve the network capacity. In this paper, we propose a software-defined mmWave network architecture, where a centralized controller is introduced by abstracting the cross-layer control functions from the network layer to physical layer. Efficient coordination is achieved in this architecture to maximize the spatial reuse.