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Impact of bursty error rates on the performance of wireless local area network (WLAN)

Ad Hoc Networks 2006年第5期4卷 651-668页

作者： Yin, Jun Wang, Xiaodong Agrawal, Dharma P. OBR Center of Distributed and Mobile Computing Department of ECECS University of Cincinnati Cincinnati OH 45221-0030 United States

With an increasing popularity of DCF based wireless LAN, the modeling of 802.11 distributed coordination function (DCF) has attracted lots of research attention. Existing analysis of 802.11 DCF has been focused on the determination of the throughput and the packet delay under saturated traffic and ideal channel conditions. Although some recent papers address the saturated performance under a simple uniform error model, they can hardly capture the impact of bursty characteristics of wireless fading on the performance of 802.11 DCF. This paper presents exact formulae for the throughput and the delay in DCF for various traffic conditions when either saturated or unsaturated traffic load is present. A two-state Markov channel model is incorporated to present the bursty characteristics of channel errors. With our analysis, the impact of bursty channel error on unsuccessful transmission probability and the DCF performance can be determined. The results of our analytical framework reveal that the four-way handshaking scheme does not improve throughput substantially for light traffic load. However, for heavy traffic load, the four-way handshaking scheme is advantageous as compared to the basic access scheme. Also, extensive simulation is done to substantiate the accuracy of our analytical model. © 2005 Elsevier B.V. All rights reserved.

关键词： Wireless telecommunication systems

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On-demand reliable medium access in sensor networks 06

On-demand reliable medium access in sensor networks

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WoWMoM 2006: 2006 International Symposium on a World of Wireless, mobile and Multimedia Networks

作者： Biswas, Ratnabali Jain, Vivek Ghosh, Chittabrata Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati

ISBN: (纸本)0769525938

A wireless sensor network typically consists of a dense deployment of sensor nodes to achieve higher resolution and better network coverage. Having a dense network increases the fault-tolerance and robustness of the system. However, if not properly handled, it can lead to more collisions during transmission and also network congestion. Furthermore, wireless communication is inherently unpredictable and error-prone. Hence, it is imperative to design an efficient medium access control (MAC) protocol that facilitates guaranteed delivery of data over unreliable wireless links. In this paper, we have designed an on-demand reliable MAC (RMAC) protocol that enables timely delivery of data. We have demonstrated its superior performance over existing reliability-enforcing approaches in terms of reliability, latency, scalability and energy-efficiency. © 2006 IEEE.

关键词： Telecommunication networks

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Supporting MAC layer multicast in IEEE 802.11 based MANETs: Issues and solutions

Supporting MAC layer multicast in IEEE 802.11 based MANETs: ...

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Proceedings - 29th Annual IEEE International Conference on Local Computer Networks, LCN 2004

作者： Gossain, Hrishikesh Nandiraju, Nagesh Anand, Kumar Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Cincinnati OH 45221-0030

In an IEEE 802.11 based mobile Ad Hoc Networks (MANETs) multicast packets are generally forwarded as one hop broadcast;mainly to reach all the multicast members in the neighborhood in a single transmission. Because of the broadcast property of the forwarding, packets suffer from increased instances of hidden terminal problem. Mobility of nodes makes things more difficult, and unlike unicast transmissions where MAC can detect the movement of a nexthop by making several retries, it is not possible in case of multicast forwarding. To address these issues, we propose a multicast aware MAC protocol (MMP) for MANETs. The basic objective of MMP is to provide a MAC layer support for multicast traffic. This is done by attaching an Extended Multicast Header (EMH) by the multicast agent, which provides the address of the nexthop nodes that are supposed to receive the multicast packet. The MAC layer in MMP uses the EMH field to support an ACK based data delivery. After sending the data packet, the transmitter waits for the ACK from each of its destinations in a strictly sequential order. A retransmission of the multicast packet is performed only if the ACK from any of the nodes in EMH is missing. We compare MMP with IEEE 802.11 and results show that MMP substantially improves the performance of multicast packet delivery in MANETs without creating much MAC overhead. In addition, MMP provides a better mechanism to detect the movement of its nexthop members. © 2004 IEEE.

关键词： Computer networks

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MDA: An efficient directional MAC scheme for wireless ad hoc networks

MDA: An efficient directional MAC scheme for wireless ad hoc...

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GLOBECOM'05: IEEE Global Telecommunications Conference, 2005

作者： Gossain, Hrishikesh Cordeiro, Carlos Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Cincinnati OH 45221-0030

ISBN: (纸本)0780394143

This paper addresses the issue of deafness and hidden terminal problem in a mobile Ad Hoc Networks (MANETs) using directional antennas. To minimize these effects, we propose a MAC protocol for directional Antennas (MDA) which employs an enhanced directional network allocation vector (NA V) scheme and, a novel technique of Diametrically Opposite Directions (DOD) transmission of RTS and CTS. We compare MDA with IEEE 802.11 and two recently proposed directional MAC protocols and results show that MDA outperforms these protocols in the majority of scenarios investigated. We also point out that the performance does depend on the network topology and the truffle pattern.

关键词： Network protocols

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A cross-layer approach for efficient flooding in wireless sensor networks

A cross-layer approach for efficient flooding in wireless se...

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2005 IEEE Wireless Communications and Networking Conference, WCNC 2005: Broadband Wirelss for the Masses - Ready for Take-off

作者： Wang, Xiaodong Yin, Jim Zhang, Qi Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing ECECS University of Cincinnati Cincinnati OH 45221-0030

Due to the high node density and stringent constraint on the energy consumption in wireless sensor networks, designing energy efficient flooding scheme with high reachability is critical for the operation and the lifetime of sensor networks. Many existing flooding approaches address the needs of general ad hoc networks. In contrast, this paper presents a cross-layer approach tailored specifically to the needs of sensor networks. Without assuming location awareness, a novel MAC layer access-deferring scheme based on the received signal power is proposed to reduce the collision possibility and broadcast redundancy. Local neighborhood information is piggybacked in the broadcast packet, and exploited to enhance the reachability. Simulation results show that compared with probabilistic flooding, this scheme has good performance in terms of reachability, average delay and energy efficiency. Moreover, we examine how the range estimation error and neighborhood information inaccuracy introduced by the fading environment affects the performance of our flooding scheme. © 2005 IEEE.

关键词： Wireless telecommunication systems

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Concurrent packet reception bounds of on-demand MAC protocols for multiple beam antennas

Concurrent packet reception bounds of on-demand MAC protocol...

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2006 IEEE 17th International Symposium on Personal, Indoor and mobile Radio Communications, PIMRC

作者： Jain, Vivek Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Cincinnati OH 45221 United States

ISBN: (纸本)1424403294

Multiple beam antennas can initiate several data communications concurrently by forming spatially separable beams. However, their concurrent packet reception (CPR) capability is largely governed by the underlying medium access control (MAC) protocol. In this paper, we present an analytical framework to calculate CPR upper bounds of multiple beam antennas using on-demand MAC protocols. The model can be used for adaptively changing transmission probability of the nodes so as to achieve optimal performance. We consider both transmitter-initiated and receiver initiated medium access protocols with uniform and random distribution of nodes. Using the developed model, we compute CPR capability of IEEE 802.11 DCF and ESIF based mechanisms for multiple beam antennas. We verify our model using simulations. © 2006 IEEE.

关键词： Medium access control

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IEEE 802.11 DCF based MAC protocols for multiple beam antennas and their limitations

IEEE 802.11 DCF based MAC protocols for multiple beam antenn...

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2nd IEEE International Conference on mobile Ad-hoc and Sensor Systems, MASS 2005

作者： Jain, Vivek Gupta, Anurag Lalf, Dhananjay Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Research and Technology Center Robert Bosch Corporation

ISBN: (纸本)0780394666

Multiple beam antennas can receive (or transmit) data on multiple beams simultaneously. The aim of this paper is to show the limitations of using IEEE 802.11 distributed coordination function (DCF) based schemes for medium access control (MAC) in such antennas. We provide four different variants of IEEE 802.11 DCF based on-demand protocols to study this phenomenon. Our simulation results and analyses emphasize the need to develop a novel MAC protocol to fully exploit the capabilities of multiple beam antennas. We further provide some embryonic guidelines for the development of such a protocol. © 2005 IEEE.

关键词： Network protocols

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Dynamic admission control and QoS for 802.16 wireless MAN

Dynamic admission control and QoS for 802.16 wireless MAN

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2005 Wireless Telecommunications Symposium, WTS

作者： Wang, Haitang Li, Wei Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing ECECS University of Cincinnati Cincinnati OH 45221-0030

ISBN: (纸本)0780388569

IEEE 802.16 wireless MAN is expected to revolutionize of the broadband wireless access technology. The grant/request mechanism in IEEE 802.16 MAC povides different Quality of Service (QoS)for different service flows. In the paper, we discuss the QoS issue in IEEE 802.16 wireless MANs and propose an admission control scheme for services defined in the 802.16 specifications. Our proposed scheme provides the highest priority for UGS flows and maximizes the bandwidth utilization by bandwidth borrowing and degradation. We also develop an analytical model to evaluate the svstem performance. Some numerical results are included to provide a better understanding of our scheme. © 2005 IEEE.

关键词： Wireless telecommunication systems

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Attribute allocation and retrieval scheme for large-scale sensor networks

Attribute allocation and retrieval scheme for large-scale se...

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作者： Biswas, Ratnabali Chowdhury, Kaushik Agrawal, Dharma P. OBR Research Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Cincinnati OH 45221-0030 United States

Wireless sensor network is an emerging technology that enables remote monitoring of large geographical regions. In this paper, we address the problem of distributing attributes over such a large-scale sensor network so that the cost of data retrieval is minimized. The proposed scheme is a data-centric storage scheme where the attributes are distributed over the network depending on the correlations between them. The problem addressed here is similar to the Allocation Problem of distributed databases. In this paper, we have defined the Allocation Problem in the context of sensor networks and have proposed a scheme for finding a good distribution of attributes to the sensor network. We also propose an architecture for query processing given such a distribution of attributes. We analytically determine the conditions under which the proposed architecture is beneficial and present simulation results to demonstrate the same. To the best of our knowledge, this is the first attempt to determine an allocation of attributes over a sensor network based on the correlations between attributes. © Springer Science+Business Media, LLC 2006.

关键词： Wireless telecommunication systems

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A cross layer MAC with explicit synchronization through intelligent feedback for multiple beam antennas

A cross layer MAC with explicit synchronization through inte...

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GLOBECOM'05: IEEE Global Telecommunications Conference, 2005

作者： Jain, Vivek Gupta, Anurag Lal, Dhananjay Agrawal, Dharma P. OBR Center for Distributed and Mobile Computing Department of ECECS University of Cincinnati Research and Technology Center Robert Bosch Corporation

ISBN: (纸本)0780394143

This paper introduces a novel cross layer medium access control protocol for multiple beam antennas to fully utilize their multiple-beam-forming capability. Our protocol, Explicit Synchronization via Intelligent Feedback (ESIF), uses feedback from neighboring nodes to synchronize data communication at multiple beams. ESIF exploits routing information to guarantee long-term fairness and minimize the energy and latency overheads. Unlike previous works on directional antennas that discuss range extension, we focus on optimal spatial reuse. Simulation results demonstrate that ESIF outperforms other ondemand access schemes based on IEEE 802.11 DCF for multiple beam antennas.

关键词： Antenna arrays

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