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Title: Energy-efficient target coverage in heterogeneous wireless sensor networks.
Creator: Awada, Wael, Florida Atlantic University, Cardei, Mihaela
Abstract/Description: We consider a heterogeneous wireless sensor network, which has several supernodes for data relay and a large number of energy-constrained sensor nodes that are deployed randomly to cover certain targets. Since targets are covered by many sensors, we create several cover sets that are active successively to save power. We introduce the Heterogeneous Connected Set Covers (HCSC) which aims to find at least one cover set that covers all the targets and is connected to a data-relaying supernode. A...
Show moreWe consider a heterogeneous wireless sensor network, which has several supernodes for data relay and a large number of energy-constrained sensor nodes that are deployed randomly to cover certain targets. Since targets are covered by many sensors, we create several cover sets that are active successively to save power. We introduce the Heterogeneous Connected Set Covers (HCSC) which aims to find at least one cover set that covers all the targets and is connected to a data-relaying supernode. A sensor node can participate in different set covers but the sum of energy spent in all sets is constrained by the initial energy resources of that sensor node. This is the first solution proposed for the target coverage in heterogeneous wireless sensor networks. We show that the HCSC is an NP-Complete problem and propose three distributed algorithms for it and showing simulation results to verify the proposed approaches.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13342
Subject Headings: Wireless communication systems, Sensor networks, Wireless LANs
Format: Document (PDF)

Title: Implementation of the Sensor-MAC protocol for the JiST/SWANS simulator.
Creator: Tippanagoudar, Veerendra., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: In recent years, advances in wireless technologies have enabled novel applications for wireless devices. Sensor network is one such application that consists of large number of battery-operated nodes. To simulate such networks with large number of nodes, a wireless sensor network simulator that is highly scalable is vital. JiST/SWANS is one such simulator that is highly scalable. However, the JiST/SWANS MAC layer implementation of 802.11b is not suitable for sensor networks, which are energy...
Show moreIn recent years, advances in wireless technologies have enabled novel applications for wireless devices. Sensor network is one such application that consists of large number of battery-operated nodes. To simulate such networks with large number of nodes, a wireless sensor network simulator that is highly scalable is vital. JiST/SWANS is one such simulator that is highly scalable. However, the JiST/SWANS MAC layer implementation of 802.11b is not suitable for sensor networks, which are energy-constrained. Hence, our main focus is to implement the S-MAC protocol in JiST/SWANS. The S-MAC protocol allows the nodes to go to sleep and thereby it helps conserve energy. This subsequently helps the nodes to extend their effective lifetime. We validate our S-MAC protocol implementation in the JiST/SWANS through simulations.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13396
Subject Headings: Wireless communication systems, Sensor networks, Wireless LANs
Format: Document (PDF)

Title: Design and implementation of an energy model for JiST/SWANS simulator.
Creator: Sutaria, Trishla., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Wireless sensor networks are one of the first real world examples of pervasive computing, the notion that small, smart, and cheap sensing and computing devices will eventually permeate the environment. Sensor networks consist of very large number of energy constrained nodes and to properly evaluate these networks a scalable ad-hoc wireless network simulator with an energy model is needed. Since most of the existing simulators have been designed for ad-hoc network with low scalability they can...
Show moreWireless sensor networks are one of the first real world examples of pervasive computing, the notion that small, smart, and cheap sensing and computing devices will eventually permeate the environment. Sensor networks consist of very large number of energy constrained nodes and to properly evaluate these networks a scalable ad-hoc wireless network simulator with an energy model is needed. Since most of the existing simulators have been designed for ad-hoc network with low scalability they can not be used to accurately simulate sensor networks. The JiST/SWANS simulator is one of the newer simulators that has been developed by Cornell University for simulating ad-hoc networks and is highly scalable which makes it appropriate for use in evaluating sensor networks. Since this simulator lack energy model our objective is to design and implement an energy model for JiST/SWANS so that it can adequately and accurately calculate the amount of energy consumption in the simulation of sensor networks.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13275
Subject Headings: Sensor networks, Wireless LANs, Computer network protocols, Wireless communication systems
Format: Document (PDF)

Title: Energy-efficient protocols for wireless sensor networks.
Creator: Du, Kemei., Florida Atlantic University, Wu, Jie
Abstract/Description: This thesis describes energy-conserving techniques in wireless sensor networks. In wireless sensor networks the sensor nodes gather information and send the information to a base station periodically. Some important messages need be broadcast to all nodes. Due to the limited battery capacity in sensor nodes, energy efficiency is becoming a major challenging problem in these power-constrained networks. Chain-based protocols construct a transmission chain connecting all nodes to save energy...
Show moreThis thesis describes energy-conserving techniques in wireless sensor networks. In wireless sensor networks the sensor nodes gather information and send the information to a base station periodically. Some important messages need be broadcast to all nodes. Due to the limited battery capacity in sensor nodes, energy efficiency is becoming a major challenging problem in these power-constrained networks. Chain-based protocols construct a transmission chain connecting all nodes to save energy dissipation of data transmission. We propose a multiple-chain scheme for all-to-all broadcasting. Furthermore, we develop an energy-efficient chain-construction algorithm which uses a sequence of insertions to minimize the energy consumption along the chain. We propose an energy-based adaptive clustering protocol, in which cluster-head elections depend on not only a probabilistic model but also the remaining energy in each node. This protocol improves the life time of the network by distributing energy usage effectively among the sensor nodes.
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Date Issued: 2002
PURL: http://purl.flvc.org/fcla/dt/12912
Subject Headings: Wireless communication systems, Computer network protocols
Format: Document (PDF)

Title: A reduced overhead routing protocol for ad hoc wireless networks.
Creator: Ibriq, Jamil, Florida Atlantic University, Wu, Jie
Abstract/Description: This document describes the Reduced Overhead Routing (ROR) protocol for use in mobile wireless ad hoc networks. The protocol is highly bandwidth-efficient. The protocol has three distinguishing features: First, it maintains, for each destination, multiple paths. Second, routing table updates are localized. Updates are initiated only when the update table is not empty and the update frequency has not exceeded a specified rate. Third, ROR uses threshold routing technique; it allows an...
Show moreThis document describes the Reduced Overhead Routing (ROR) protocol for use in mobile wireless ad hoc networks. The protocol is highly bandwidth-efficient. The protocol has three distinguishing features: First, it maintains, for each destination, multiple paths. Second, routing table updates are localized. Updates are initiated only when the update table is not empty and the update frequency has not exceeded a specified rate. Third, ROR uses threshold routing technique; it allows an intermediate node to deliver data packet via a longer sub-optimal route that is within the distance. To prevent frequent updates, at most one update is initiated every predefined period of time. A node transmits each update with propagation radius that is determined on the basis of node's network region using a novel probabilistic technique. Threshold routing and localized probabilistic updates greatly reduce routing overhead and network congestion and improve bandwidth efficiency.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/12703
Subject Headings: Mobile computing, Computer networks, Wireless communication systems
Format: Document (PDF)

Title: Simulation-based performance evaluation of AODV routing protocol for ad hoc mobile wireless networks.
Creator: Suryaprasad, Deepa., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: An ad hoc wireless network is a network composed of mobile communication devices, which is designed to provide communication capability to satisfy the need of a temporary nature in an infrastructure-less environment. A routing protocol is necessary in ad hoc networks to ensure effective communication among nodes. This thesis presents a simulation-based study on the performance evaluation of Ad hoc on-demand distance vector (AODV) routing protocol, which is one of the core routing protocols...
Show moreAn ad hoc wireless network is a network composed of mobile communication devices, which is designed to provide communication capability to satisfy the need of a temporary nature in an infrastructure-less environment. A routing protocol is necessary in ad hoc networks to ensure effective communication among nodes. This thesis presents a simulation-based study on the performance evaluation of Ad hoc on-demand distance vector (AODV) routing protocol, which is one of the core routing protocols being promoted by the Mobile Ad Hoc Networking (MANET) group of the Internet Engineering Task Force. An event-advanced simulation program was developed in C++ to simulate the ad hoc wireless network implementing the AODV protocol. The performance metrics evaluated were throughput, average delay, route acquisition time and routing overhead. The network traffic was monitored in terms of the data packets created and successfully delivered within the simulation time. A discussion on the effect of different network parameters such as the mobility of the nodes, the number of nodes in the network, the size of the network and the data packet size on the performance characteristics of AODV protocol is also presented.
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Date Issued: 2003
PURL: http://purl.flvc.org/fcla/dt/12989
Subject Headings: Computer network protocols, Wireless communication systems
Format: Document (PDF)

Title: Analysis of quality of service (QoS) in WiMAX networks.
Creator: Talwalkar, Rohit., College of Engineering and Computer Science, Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: In last few years there has been significant growth in the area of wireless communication. Quality of Service (QoS) has become an important consideration for supporting variety of applications that utilize the network resources. These applications include voice over IP, multimedia services, like, video streaming, video conferencing etc. IEEE 802.16/WiMAX is a new network which is designed with quality of service in mind. This thesis focuses on analysis of quality of service as implemented by...
Show moreIn last few years there has been significant growth in the area of wireless communication. Quality of Service (QoS) has become an important consideration for supporting variety of applications that utilize the network resources. These applications include voice over IP, multimedia services, like, video streaming, video conferencing etc. IEEE 802.16/WiMAX is a new network which is designed with quality of service in mind. This thesis focuses on analysis of quality of service as implemented by the WiMAX networks. First, it presents the details of the quality of service architecture in WiMAX network. In the analysis, a WiMAX module developed based on popular network simulator ns-2, is used. Various real life scenarios like voice call, video streaming are setup in the simulation environment. Parameters that indicate quality of service, such as, throughput, packet loss, average jitter and average delay, are analyzed for different types of service flows as defined in WiMAX. Results indicate that better quality of service is achieved by using service flows designed for specific applications.
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Date Issued: 2008
PURL: http://purl.flvc.org/fcla/flaent/EN00154040/68_2/98p0143h.pdf, http://purl.flvc.org/FAU/58012
Subject Headings: Wireless communication systems, Broadband communication systems, Wireless LANs, Design and construction, Computer networks, Management, Quality control
Format: Document (PDF)

Title: Performance Analysis of Spectrum Sensing Schemes Based on Fractional Lower Order Moments for Cognitive Radios in Alpha- Stable Noise Environments.
Creator: Ackie, A-Bon Elfick, Aalo, Valentine A., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Natural and manmade noise signals tend to exhibit impulsive behaviors. Therefore modeling those signals as α-stable processes is better suited towards the development of a practical spectrum sensing scheme. However, the performances of detectors operating in an α-stable noise environment are difficult to evaluate. This is because an α-stable random variable can usually only be modeled by the characteristic function since closed-form expressions are usually not available except for the special...
Show moreNatural and manmade noise signals tend to exhibit impulsive behaviors. Therefore modeling those signals as α-stable processes is better suited towards the development of a practical spectrum sensing scheme. However, the performances of detectors operating in an α-stable noise environment are difficult to evaluate. This is because an α-stable random variable can usually only be modeled by the characteristic function since closed-form expressions are usually not available except for the special values of the characteristic exponent that correspond to the Cauchy and Gaussian noise distributions. In this thesis, we derive a general closed-form expression for the probability density function (PDF) of symmetric alpha stable processes having rational characteristic exponent (0<α≤2). Consequently, we obtain analytical expressions for the PDF and corresponding complementary cumulative distribution function (CCDF) of the proposed fractional lower order moment (FLOM) detector. Utilizing false alarm and detection probabilities, the performance analysis of the proposed spectrum sensing scheme is conducted with the assumption that the cognitive radio (CR) users are operating in non-fading channels. We validate the analytical results with Monte Carlo simulations. The effect of the distribution parameters on the receiver operating characteristic (ROC) curves is verified.
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Date Issued: 2016
PURL: http://purl.flvc.org/fau/fd/FA00004561, http://purl.flvc.org/fau/fd/FA00004561
Subject Headings: Cognitive radio networks., Radio frequency allocation., Radio resource management (Wireless communications), Wireless communication systems.
Format: Document (PDF)

Title: Adaptive on-demand routing protocol for mobile ad hoc networks.
Creator: Omer, Ismail., Florida Atlantic University, Mahgoub, Imad, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Existing MANET routing protocols can be classified into three categories: On-demand, Proactive, and Proactive-On-demand hybrid protocols. This dissertation presents a novel hybrid MANET routing protocol, Adaptive On-demand MANET Routing (AOMAR) protocol. AOMAR borrowed the concepts of temporal location updates in operating systems and cache memories to reconstruct broken routes. Each route entry in a mobile host will have a reference field that is set to indicate whether the route is used...
Show moreExisting MANET routing protocols can be classified into three categories: On-demand, Proactive, and Proactive-On-demand hybrid protocols. This dissertation presents a novel hybrid MANET routing protocol, Adaptive On-demand MANET Routing (AOMAR) protocol. AOMAR borrowed the concepts of temporal location updates in operating systems and cache memories to reconstruct broken routes. Each route entry in a mobile host will have a reference field that is set to indicate whether the route is used within a certain period of time called refresh time. Using the refresh time parameter and the route reference field, AOMAR behavior can be controlled to behave as pure On-demand, Adaptive, or history related Proactive protocol. The three versions of AOMAR, On-demand, Adaptive and Proactive, have been simulated using different network sizes, loads and mobility patterns. Three performance metrics---throughput, delay and overhead---are collected. The results show that AOMAR on-demand has the same pattern of results when compared with other exiting on-demand protocols. On-demand AOMAR shows better performance when compared to Adaptive AOMAR for simulation sessions with uniform workloads. On the other hand Adaptive AOMAR outperforms On-demand AOMAR for simulation sessions with non-uniform workloads. Proactive AOMAR reconstructs recently used routes that have broken. Therefore, its routing overhead results change with the change of the network loads and mobility rates. This is not the case for traditional proactive protocols. Proactive AOMAR has lower control overhead and saves the bandwidth when compared with traditional existing proactive routing protocols. In addition to developing and simulating AOMAR, a new mobility model is proposed. Synchronized Random Direction Model of Motion with Constant Speed (SRDMCS) is a model that is suitable to emulate objects that move in random directions with a constant speed and within a certain area of movement. A new formula, Movement Related Update (MRU), is proposed and implemented. In MRU, the refresh period parameter value is linked to the network mobility level. Using MRU in the simulation gives AOMAR a third dimension such that the protocol not only adapts with how frequently the routes are used and how frequently they are broken, but also with how dynamic the network is.
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Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/11972
Subject Headings: Mobile computing, Computer network protocols, Wireless communication systems
Format: Document (PDF)

Title: Design and implementation of a wireless ad hoc network.
Creator: Neelakanta, Mahesh., Florida Atlantic University, Hsu, Sam, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: This thesis addresses issues faced in the practical implementation of a wireless ad hoc network (WAHN) protocol for data transmission. This study focuses on: (1) Evaluating existing hardware and software options available for the WAHN implementation. (2) Appraising the issues faced while implementing a practical wireless ad hoc protocol. (3) Applying a set of MAC protocol specifications developed for a wireless ad hoc data network to a practical test network. Specific to the above topics of...
Show moreThis thesis addresses issues faced in the practical implementation of a wireless ad hoc network (WAHN) protocol for data transmission. This study focuses on: (1) Evaluating existing hardware and software options available for the WAHN implementation. (2) Appraising the issues faced while implementing a practical wireless ad hoc protocol. (3) Applying a set of MAC protocol specifications developed for a wireless ad hoc data network to a practical test network. Specific to the above topics of interest, the following research tasks are performed: (1) An elaborate survey and relevant discussions on wireless MAC protocols. (2) A comprehensive study comparing various wireless transceivers is performed. Range, data rate, frequency, interfacing method and cost are the factors compared. (3) A simple, low-cost and low baud-rate transceiver is modified with appropriate interface circuits to support wireless communications. A more advanced transceiver is also considered and used for the software foundation of a practical implementation of the ad hoc and MAC protocols. The studies enable assessing the problems faced during the implementation and suggest solutions to resolve these problems. Further areas for study are also discussed.
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Date Issued: 1998
PURL: http://purl.flvc.org/fcla/dt/15615
Subject Headings: Wireless communication systems, Data transmission systems, Computer networks
Format: Document (PDF)

Title: A communication protocol for wireless sensor networks.
Creator: Callaway, Edgar Herbert, Jr., Florida Atlantic University, Shankar, Ravi, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Many wireless network applications, such as wireless computing on local area networks, employ data throughput as a primary performance metric. The data throughput on such networks has therefore been increasing in recent years. However, there are other potential wireless network applications, such as industrial monitoring and control, consumer home automation, and military remote sensing, that have relaxed throughput requirements, often measured in bits/day. Such networks have power...
Show moreMany wireless network applications, such as wireless computing on local area networks, employ data throughput as a primary performance metric. The data throughput on such networks has therefore been increasing in recent years. However, there are other potential wireless network applications, such as industrial monitoring and control, consumer home automation, and military remote sensing, that have relaxed throughput requirements, often measured in bits/day. Such networks have power consumption and cost as primary performance metrics, rather than data throughput, and have been called wireless sensor networks. This work describes a physical layer, a data link layer, and a network layer design suitable for use in wireless sensor networks. To minimize node duty cycle and therefore average power consumption, while minimizing the symbol rate, the proposed physical layer employs a form of orthogonal multilevel signaling in a direct sequence spread spectrum format. Results of Signal Processing Worksystem (SPW, Cadence, Inc.) simulations are presented showing a 4-dB sensitivity advantage of the proposed modulation method compared to binary signaling, in agreement with theory. Since the proposed band of operation is the 2.4 GHz unlicensed band, interference from other services is possible; to address this, SPW simulations of the proposed modulation method in the presence of Bluetooth interference are presented. The processing gain inherent in the proposed spread spectrum scheme is shown to require the interferer to be significantly stronger than the desired signal before materially affecting the received bit error rate. The proposed data link layer employs a novel distributed mediation device (MD) technique to enable networked nodes to synchronize to each other, even when the node duty cycle is arbitrarily low (e.g., <0.1%). This technique enables low-cost devices, which may employ only low-stability time bases, to remain asynchronous to one another, becoming synchronized only when communication is necessary between them. Finally, a wireless sensor network design is presented. A cluster-type architecture is chosen; the clusters are organized in a hierarchical tree to simplify the routing algorithm. Results of several network performance metrics simulations, including the effects of the distributed MD dynamic synchronization scheme, are presented, including the average message latency, node duty cycle, and data throughput. The architecture is shown to represent a practical alternative for the design of wireless sensor networks.
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Date Issued: 2002
PURL: http://purl.flvc.org/fcla/dt/11991
Subject Headings: Wireless communication systems, Computer network protocols, Radio detectors
Format: Document (PDF)

Title: Low latency and energy efficient MAC protocols for wireless sensor networks.
Creator: Abu-El Humos, Ali M., Florida Atlantic University, Alhalabi, Bassem A., Cardei, Mihaela, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Energy consumption is a critical design issue in Wireless Sensor Networks (WSNs), since sensor nodes are battery operated, and replacing or recharging the battery is usually infeasible. Energy efficient solutions are sought at all network levels, especially at the medium access level. The IEEE 802.11 MAC protocol is optimized for Ad hoc Wireless Networks, but cannot be adopted for WSNs because it has the idle listening problem, which is a major source of energy waste. Several Medium Access...
Show moreEnergy consumption is a critical design issue in Wireless Sensor Networks (WSNs), since sensor nodes are battery operated, and replacing or recharging the battery is usually infeasible. Energy efficient solutions are sought at all network levels, especially at the medium access level. The IEEE 802.11 MAC protocol is optimized for Ad hoc Wireless Networks, but cannot be adopted for WSNs because it has the idle listening problem, which is a major source of energy waste. Several Medium Access Control (MAC) protocols have been proposed for WSNs to save the transceiver energy by introducing periodic listen/sleep cycles, and thus overcome the idle listing problem. The periodic listen sleep cycles, however, will increase the network latency and require extra overhead to establish and maintain synchronization among nodes in the network. This dissertation introduces a new MAC protocol for WSNs based on the SMAC protocol to improve its latency performance without compromising its energy consumption. The original SMAC provides an efficient solution for the energy consumption problem due to idle listening, but it increases latency especially in low duty cycle applications. TMAC was proposed to further reduce the energy consumption in SMAC and introduced the Forward Request-To-Send (FRTS) packet to solve the early sleep problem observed in TMAC. Later, Adaptive SMAC was proposed to reduce the latency problem in SMAC by at least 50% at light traffic load. Our new protocol, FASMAC, combines the advantages of both adaptive listening and the usage of FRTS packet in TMAC to further reduce the latency of SMAC. In FASMAC, a packet can travel at least three hops away from its source node within one time cycle. This results in at least 67% reduction in latency at light traffic when compared with the original SMAC. We also propose an energy model for performance evaluation of WSNs protocols using the network simulator NS2. The current energy model of NS2 was designed to handle Ad hoc Wireless Networks where the low power consumption sleep mode was not an issue. However, this is not the case in WSNs. We show that NS2 energy model is not suitable to evaluate the performance of WSNs protocols because it does not account for the low power sleep mode. This dissertation proposes a solution to this deficiency and provides simulation results that match real experimental results performed on the actual sensor motes.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/12149
Subject Headings: Wireless communication systems, Sensor networks, Power resources--Efficiency
Format: Document (PDF)

Title: Quorum based IP autoconfiguration in mobile ad hoc networks.
Creator: Xu, Tinghui., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: IP address autoconfiguration poses a challenge for mobile ad-hoc networks (MANETs) because it has to be done to ensure correct routing. An IP autoconfiguration protocol that is based on quorum voting is proposed. Nodes are distributed configured when a write quorum can be collected. Making the compromise between message overhead and data consistency, quorum voting enforces data consistency by ensuring fresh read on every access so that each node is configured with a unique IP address. The...
Show moreIP address autoconfiguration poses a challenge for mobile ad-hoc networks (MANETs) because it has to be done to ensure correct routing. An IP autoconfiguration protocol that is based on quorum voting is proposed. Nodes are distributed configured when a write quorum can be collected. Making the compromise between message overhead and data consistency, quorum voting enforces data consistency by ensuring fresh read on every access so that each node is configured with a unique IP address. The protocol is scalable since the configuration information is maintained locally and no central server is involved. Extensive experiments are carried out comparing the configuration latency, message overhead and address reclamation cost between our protocol and existing stateful protocols. The simulation results show that nodes are configured in lower latency and the message overhead for maintaining the network is fairly low. Moreover, the proposed protocol greatly enhances the address availability by keeping proper redundancy.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13362
Subject Headings: TCP/IP (Computer network protocol), Computer network architectures, Mobile communication systems, Wireless communication systems
Format: Document (PDF)

Title: Adaptive hierarchical weighted fair queuing scheduling in WiMAX networks.
Creator: AL-Ghanem, Waleed Khalid, Ilyas, Mohammad, Mahgoub, Imad, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The growing demand for faster connection to the Internet service and wireless multimedia applications has motivated the development of broadband wireless access technologies in recent years. WiMAX has enabled convergence of mobile and fixed broadband networks through a common wide-area radio-access technology and flexible network architecture. Scheduling is a fundamental component in resource management in WiMAX networks and plays the main role in meeting QoS requirements such as delay,...
Show moreThe growing demand for faster connection to the Internet service and wireless multimedia applications has motivated the development of broadband wireless access technologies in recent years. WiMAX has enabled convergence of mobile and fixed broadband networks through a common wide-area radio-access technology and flexible network architecture. Scheduling is a fundamental component in resource management in WiMAX networks and plays the main role in meeting QoS requirements such as delay, throughput and packet loss for different classes of service. In this dissertation work, the performance of uplink schedulers at the fixed WiMAX MAC layer has been considered, we proposed an Adaptive Hierarchical Weighted Fair Queuing Scheduling algorithm, the new scheduling algorithm adapts to changes in traffic, at the same time; it is able to heuristically enhance the performance of WiMAX network under most circumstances. The heuristic nature of this scheduling algorithm enables the MAC layer to meet the QoS requirements of the users. The performance of this adaptive WiMAX Uplink algorithm has been evaluated by simulation using MATLAB. Results indicate that the algorithm is efficient in scheduling the Base Stations’ traffic loads, and improves QoS. The utilization of relay stations is studied and simulation results are compared with the case without using relay stations. The results show that the proposed scheduling algorithm improves Quality of Service of WiMAX system.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004178, http://purl.flvc.org/fau/fd/FA00004178
Subject Headings: Computer networks -- Technological innovations, Optical fiber communication, Wireless communication systems -- Technological innovations, Wireless metropolitan area networks -- Security measures
Format: Document (PDF)

Title: Probabilistic predictor-based routing in disruption-tolerant networks.
Creator: Yuan, Quan., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Disruption-Tolerant Networks (DTNs) are the networks comprised of a set of wireless nodes, and they experience unstable connectivity and frequent connection disruption because of the limitations of radio range, power, network density, device failure, and noise. DTNs are characterized by their lack of infrastructure, device limitation, and intermittent connectivity. Such characteristics make conventional wireless network routing protocols fail, as they are designed with the assumption the...
Show moreDisruption-Tolerant Networks (DTNs) are the networks comprised of a set of wireless nodes, and they experience unstable connectivity and frequent connection disruption because of the limitations of radio range, power, network density, device failure, and noise. DTNs are characterized by their lack of infrastructure, device limitation, and intermittent connectivity. Such characteristics make conventional wireless network routing protocols fail, as they are designed with the assumption the network stays connected. Thus, routing in DTNs becomes a challenging problem, due to the temporal scheduling element in a dynamic topology. One of the solutions is prediction-based, where nodes mobility is estimated with a history of observations. Then, the decision of forwarding messages during data delivery can be made with that predicted information. Current prediction-based routing protocols can be divided into two sub-categories in terms of that whether they are probability related: probabilistic and non-probabilistic. This dissertation focuses on the probabilistic prediction-based (PPB) routing schemes in DTNs. We find that most of these protocols are designed for a specified topology or scenario. So almost every protocol has some drawbacks when applied to a different scenario. Because every scenario has its own particular features, there could hardly exist a universal protocol which can suit all of the DTN scenarios. Based on the above motivation, we investigate and divide the current DTNs scenarios into three categories: Voronoi-based, landmark-based, and random moving DTNs. For each category, we design and implement a corresponding PPB routing protocol for either basic routing or a specified application with considering its unique features., Specifically, we introduce a Predict and Relay routing protocol for Voronoi-based DTNs, present a single-copy and a multi-copy PPB routing protocol for landmark-based DTNs, and propose DRIP, a dynamic Voronoi region-based publish/subscribe protocol, to adapt publish/subscribe systems to random moving DTNs. New concepts, approaches, and algorithms are introduced during our work.
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Date Issued: 2009
PURL: http://purl.flvc.org/FAU/359928
Subject Headings: Routers (Computer networks), Computer network protocols, Computer networks, Reliability, Computer algorithms, Wireless communication systems, Technological innovations
Format: Document (PDF)

Title: Performance analysis of multi-base station slotted ALOHA for wireless LAN in a Nakagami fading environment.
Creator: Chopra, Anju S., Florida Atlantic University, Aalo, Valentine A.
Abstract/Description: Capture effect has shown considerable improvement on performance of slotted ALOHA systems. Further, improvement is expected by increasing the number of base stations. The performance of such slotted ALOHA systems is analyzed with the aid of Equilibrium point analysis. Packet dropping due to finite number of retransmissions is taken into account. The numerical results indicate that the finite number of retransmission trials mainly contribute to the improvement of the packet dropping...
Show moreCapture effect has shown considerable improvement on performance of slotted ALOHA systems. Further, improvement is expected by increasing the number of base stations. The performance of such slotted ALOHA systems is analyzed with the aid of Equilibrium point analysis. Packet dropping due to finite number of retransmissions is taken into account. The numerical results indicate that the finite number of retransmission trials mainly contribute to the improvement of the packet dropping probability in the range of light input traffic. The use of multiple base stations improves the overall throughput and the average transmission delay in the range of heavy input traffic.
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Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15268
Subject Headings: Local area networks (Computer networks), Wireless communication systems, Packet switching (Data transmission), Computer network protocols
Format: Document (PDF)

Title: Reputation-based system for encouraging cooperation of nodes in mobile ad hoc networks.
Creator: Anantvalee, Tiranuch., Florida Atlantic University, Wu, Jie
Abstract/Description: In a mobile ad hoc network, node cooperation in packet forwarding is required for the network to function properly. However, since nodes in this network usually have limited resources, some selfish nodes might intend not to forward packets to save resources for their own use. To discourage such behavior, we propose RMS, a reputation-based system, to detect selfish nodes and respond to them by showing that being cooperative will benefit there more than being selfish. We also detect, to some...
Show moreIn a mobile ad hoc network, node cooperation in packet forwarding is required for the network to function properly. However, since nodes in this network usually have limited resources, some selfish nodes might intend not to forward packets to save resources for their own use. To discourage such behavior, we propose RMS, a reputation-based system, to detect selfish nodes and respond to them by showing that being cooperative will benefit there more than being selfish. We also detect, to some degree, nodes who forward only the necessary amount of packets to avoid being detected as selfish. We introduce the use of a state model to decide what we should do or respond to nodes in each state. In addition, we introduce the use of a timing period to control when the reputation should be updated and to use as a timeout for each state. The simulation results show that RMS can identify selfish nodes and punish them accordingly, which provide selfish nodes with an incentive to behave more cooperatively.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13406
Subject Headings: Computer networks--Security measures, Wireless communication systems, Routers (Computer networks), Computer network architectures
Format: Document (PDF)

Title: Simulation study of beacon time synchronization algorithm in low rate wireless personal area networks.
Creator: Shrivastav, Madhu., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: In a beacon-enabled network, nodes send beacons when they are ready to transmit or receive messages from the other sensors in their communication range. If the beacons are not synchronized in time, a sensor might receive more than one beacon and hence will not be able to demodulate the beacon, thereby, being isolated from the network. As a result coverage nulls are introduced in the system. To address the above mentioned issues, Motorola Labs have proposed an algorithm for synchronizing the...
Show moreIn a beacon-enabled network, nodes send beacons when they are ready to transmit or receive messages from the other sensors in their communication range. If the beacons are not synchronized in time, a sensor might receive more than one beacon and hence will not be able to demodulate the beacon, thereby, being isolated from the network. As a result coverage nulls are introduced in the system. To address the above mentioned issues, Motorola Labs have proposed an algorithm for synchronizing the beacons in a wireless personal area network. In this thesis, extensive study of the proposed beacon time synchronization algorithm is done using OPNET as a simulation tool. Simulation is carried out by designing a detailed model of the algorithm using IEEE 802.15.4 as a reference. In depth analysis of the simulation results has been carried out. The results obtained are compared with those of existing time synchronization methods.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13227
Subject Headings: Wireless LANs, Extranets (Computer networks), Wireless communication systems, Data transmission systems, Computer network protocols, Home computer networks
Format: Document (PDF)

Title: Joint TCP congestion control and wireless-link scheduling for mobile Internet applications.
Creator: Li, Zhaoquan., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The Transmission Control Protocol (TCP) is one of the core protocols of the Internet protocol suite, which is used by major Internet applications such as World Wide Web, email, remote administration and file transfer. TCP implements scalable and distributed end-to-end congestion control algorithms to share network resources among competing users. TCP was originally designed primarily for wired networks, and it has performed remarkably well as the Internet scaled up by six orders of magnitude...
Show moreThe Transmission Control Protocol (TCP) is one of the core protocols of the Internet protocol suite, which is used by major Internet applications such as World Wide Web, email, remote administration and file transfer. TCP implements scalable and distributed end-to-end congestion control algorithms to share network resources among competing users. TCP was originally designed primarily for wired networks, and it has performed remarkably well as the Internet scaled up by six orders of magnitude in the past decade. However, many studies have shown that the unmodified standard TCP performs poorly in networks with large bandwidth-delay products and/or lossy wireless links. In this thesis, we analyze the problems TCP exhibits in the wireless communication environment, and develop joint TCP congestion control and wireless-link scheduling schemes for mobile applications. ... Different from the existing solutions, the proposed schemes can be asynchronously implemented without message passing among network nodes; thus they are readily deployable with current infrastructure. Moreover, global convergence/stability of the proposed schemes to optimal equilibrium is established using the Lyapunov method in the network fluid model. Simulation results are provided to evaluate the proposed schemes in practical networks.
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Date Issued: 2013
PURL: http://purl.flvc.org/fcla/dt/3362481
Subject Headings: Wireless communication systems, Quality control, Mobile communication systems, Technological innovations, TCP/IP (Computer network protocol), Ad hoc networks (Computer networks), Computer network protocols, Wireless Internet
Format: Document (PDF)

Title: Mechanisms for prolonging network lifetime in wireless sensor networks.
Creator: Yang, Yinying., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Sensors are used to monitor and control the physical environment. A Wireless Sen- sor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using hop-by-hop communication. Once a sink receives sensed data, it processes and forwards it to the users. Sensors are usually battery powered and it is...
Show moreSensors are used to monitor and control the physical environment. A Wireless Sen- sor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using hop-by-hop communication. Once a sink receives sensed data, it processes and forwards it to the users. Sensors are usually battery powered and it is hard to recharge them. It will take a limited time before they deplete their energy and become unfunctional. Optimizing energy consumption to prolong network lifetime is an important issue in wireless sensor networks. In mobile sensor networks, sensors can self-propel via springs [14], wheels [20], or they can be attached to transporters, such as robots [20] and vehicles [36]. In static sensor networks with uniform deployment (uniform density), sensors closest to the sink will die first, which will cause uneven energy consumption and limitation of network life- time. In the dissertation, the nonuniform density is studied and analyzed so that the energy consumption within the monitored area is balanced and the network lifetime is prolonged. Several mechanisms are proposed to relocate the sensors after the initial deployment to achieve the desired density while minimizing the total moving cost. Using mobile relays for data gathering is another energy efficient approach. Mobile sensors can be used as ferries, which carry data to the sink for static sensors so that expensive multi-hop communication and long distance communication are reduced. In this thesis, we propose a mobile relay based routing protocol that considers both energy efficiency and data delivery delay. It can be applied to both event-based reporting and periodical report applications., Another mechanism used to prolong network lifetime is sensor scheduling. One of the major components that consume energy is the radio. One method to conserve energy is to put sensors to sleep mode when they are not actively participating in sensing or data relaying. This dissertation studies sensor scheduling mechanisms for composite event detection. It chooses a set of active sensors to perform sensing and data relaying, and all other sensors go to sleep to save energy. After some time, another set of active sensors is chosen. Thus sensors work alternatively to prolong network lifetime.
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Date Issued: 2010
PURL: http://purl.flvc.org/FAU/1870693
Subject Headings: Wireless communication systems, Technological innovations, Wireless communication systems, Design and construction, Ad hoc networks (Computer networks), Technological innovations, Sensor networks, Design and construction, Computer algorithms, Computer network protocols
Format: Document (PDF)

Wireless communication systems (44)	+ -
Computer network protocols (23)	+ -
Technological innovations (14)	+ -
Sensor networks (13)	+ -
Computer algorithms (9)	+ -

Mobile computing (9)	+ -
Ad hoc networks (Computer networks) (8)	+ -
Computer networks (7)	+ -
Design and construction (6)	+ -
Routers (Computer networks) (6)	+ -
Security measures (6)	+ -
Wireless LANs (6)	+ -
Wireless sensor networks (5)	+ -
Code division multiple access (4)	+ -
Computer network architectures (4)	+ -
Mobile communication systems (4)	+ -
Routing protocols (Computer network protocols) (4)	+ -
Wireless communication systems--Technological innovations. (4)	+ -
Wireless communication systems. (4)	+ -
Wireless sensor networks. (4)	+ -
Computer networks--Security measures (3)	+ -
Expert systems (Computer science) (3)	+ -
Quality control (3)	+ -
Reliability (3)	+ -
Wireless communication systems -- Technological innovations (3)	+ -
Adaptive signal processing (2)	+ -
Computer algorithms. (2)	+ -
Computer security (2)	+ -
Data transmission systems (2)	+ -
Digital communications (2)	+ -

College of Engineering and Computer Science (59)	+ -
Department of Computer and Electrical Engineering and Computer Science (59)	+ -
Florida Atlantic University (50)	+ -
Wu, Jie (14)	+ -
Mahgoub, Imad (12)	+ -

Cardei, Mihaela (5)	+ -
Ilyas, Mohammad (4)	+ -
Pandya, Abhijit S. (3)	+ -
Wang, Xin (3)	+ -
AL-Ghanem, Waleed Khalid (2)	+ -
Aalo, Valentine A. (2)	+ -
Ibriq, Jamil (2)	+ -
Marcus, Anthony M. (2)	+ -
Rhodes, William T. (2)	+ -
Wang, Di (2)	+ -
Abu-El Humos, Ali M. (1)	+ -
Ackie, A-Bon Elfick (1)	+ -
Alhalabi, Bassem A. (1)	+ -
Altoaimy, Lina (1)	+ -
Alwakeel, Ahmed M. (1)	+ -
Ambrose, Arny Isonja (1)	+ -
Anantvalee, Tiranuch. (1)	+ -
Awada, Wael (1)	+ -
Badi, Ahmed. (1)	+ -
Boughen, Brian (1)	+ -
Callaway, Edgar Herbert, Jr. (1)	+ -
Cardei, Ionut E. (1)	+ -
Chopra, Anju S. (1)	+ -
Dai, Fei. (1)	+ -
Dai, Qing. (1)	+ -

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