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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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Parallel cluster formation for secured communication in wireless ad hoc networks

Parallel cluster formation for secured communication in wire...

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2004 12th IEEE International Conference on Networks, ICON 2004 - Unity in Diversity

作者： Shah, Vivek Deng, Hongmei Agrawal, Dharma P. OBR Research Center for Distributed and Mobile Computing University of Cincinnati Cincinnati OH 45221-0030 United States

ISBN: (纸本)078038783X

Routing protocols in wireless ad hoc network are highly insecure and prone to various attacks owing to its inherent characteristics of open medium, dynamically changing topologies and distributed cooperation between the member nodes. Having a secure routing protocol in wireless ad hoc networks appears to be a problem that is not trivial to solve. In this paper we mainly consider the vulnerabilities of Cluster Based Routing Protocol (CBRP), which uses formation of clusters with a single cluster head. In CBRP, cluster head has the responsibility of maintaining the cluster member list, routing the packets from the cluster members and can also be a certification authority (CA) for distribution of certificates. However a single cluster head in CBRP can be a single point of failure and can also become malicious or selfish and as a result the whole system can become paralyzed. We propose a scheme and algorithm in which we distribute the cluster head service to a group of cluster heads called Council. Each Council node will have equal functionality and utilize the (k, n) threshold secret sharing scheme for performing the cluster head functionality. One of the main functionality of Council will be key distribution. A certificate will be formed by participation of at least k nodes out of n Council member. The cluster head functionality will now be able to work even when more than one (but limited to min {k, n-k+1}) cluster heads are compromised. Simulation results of our proposed algorithm for formation of such Council based clusters demonstrates that our scheme is more fault tolerant and efficient than CBRP. © 2004 IEEE.

关键词： Security of data

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Efficient pairwise key establishment and management in static wireless sensor networks

Efficient pairwise key establishment and management in stati...

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

作者： Cheng, Yi Agrawal, Dharma P. OBR Center Distributed and Mobile Computing Lab. University of Cincinnati Cincinnati OH 45221

ISBN: (纸本)0780394666

Key establishment and management is the core of security protocols for wireless sensor networks deployed in the hostile environment. Due to the strict resource constraints, traditional asymmetric key cryptosystems, such as public/private key based schemes, are infeasible for large-scale wireless sensor networks. research shows that pre-distributing pairwise keys into wireless sensor nodes before deployment is a practical way to deal with the key establishment problem. Existing random key based key pre-distribution schemes only provide probabilistic connectivity of the network and some level of network resilience. In this paper, we propose an efficient pairwise key establishment and management scheme to achieve both network connectivity and resilience for static wireless sensor networks. Compared with current key pre-distribution schemes, our scheme supports large network size, and has lower communication and computational overhead. © 2005 IEEE.

关键词： Wireless telecommunication systems

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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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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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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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A novel distributed resource-aware scalable scheme for scatternet formation

A novel distributed resource-aware scalable scheme for scatt...

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11th IEEE International Conference on Networks, ICON 2003

作者： Dharia, Sagar I. Agrawal, Dharma P. OBR Research Center for Distributed and Mobile Computing ECECS University of Cincinnati Cincinnati OH 45221-0030 United States

ISBN: (纸本)0780377885

Bluetooth is a low-power, low-cost, short-range wireless communication system. In a Bluetooth ad hoc network, up to eight Bluetooth devices can communicate with each other in a special network called piconet. Scatternet can be formed by interconnecting piconets. In this paper, we present a distributed resource aware scalable scatternet formation algorithm. Though the proposed algorithm has two phases, it is not necessary that all the nodes be in the same phase at a given instant of time. The formed scatternet has the following properties: 1. All the devices may not be necessarily in each other's transmission range. 2. Any device will be a member of at the most two piconets. 3. Higher resource-weighted devices are preferred over lower resource-weighted devices to perform the role of a master and/or a bridge. 4. Slave/Slave bridges are preferred over Master/Slave bridges. Extensive simulations have shown that the number of messages transmitted by low resource-weighted devices are significantly lesser than the number of messages exchanged by high resource-weighted devices, and the number of master/slave bridges are remarkably less as compared to the number of slave/slave bridges. The overall message complexity of the algorithm is O(n). ©2003 IEEE.

关键词： Bluetooth

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Data-Centric Attribute Allocation and Retrieval (DCAAR) scheme for wireless sensor networks

Data-Centric Attribute Allocation and Retrieval (DCAAR) sche...

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

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

ISBN: (纸本)0780394666

Wireless sensor networks have enabled information gathering from a large geographical region and present unprecedented opportunities for a broad spectrum of monitoring applications. In this paper, we propose a data-centric storage scheme to determine a distribution of attributes over a large-scale sensor network such that the cost of retrieving data is minimized. 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. © 2005 IEEE.

关键词： Resource allocation

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distributed data aggregation in sensor networks by regression based compression

Distributed data aggregation in sensor networks by regressio...

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

作者： Banerjee, Torsha Chowdhury, Kaushik Agrawal, Dharma P. IEEE University of Cincinnati OBR Center for Distributed and Mobile Computing Cincinnati OH 45221-0030

ISBN: (纸本)0780394666

In this paper we propose a method for data compression and its subsequent regeneration using a polynomial regression technique. We approximate data received over the considered area by fitting it to a function and communicate this by passing only the coefficients that describe the function. In this paper, we extend our previous algorithm TREG to consider non-complete aggregation trees. The proposed algorithm DUMMYREG is run at each parent node and uses information present in the existing child to construct a complete binary tree. In addition to obtaining values in regions devoid of sensor nodes and reducing communication overhead, this new approach further reduces the error when the readings are regenerated at the sink. Results reveal that for a network density of 0.0025 and a complete binary tree of depth 4, the absolute error is 6%. For a non-complete binary tree, TREG returns an error of 18% while this is reduced to 12% when DUMMYREG is used. © 2005 IEEE.

关键词： Data structures

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