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Pages
- Title
- Location management in mobile networks.
- Creator
- Colucci, Raymond A., Florida Atlantic University, Mahgoub, Imad
- Abstract/Description
-
Location management in a mobile network provides functions to locate, identify, and validate a terminal or user. The purpose of this thesis is to describe a scheme that would be useful in a wireless network for managing the location of mobile users. This thesis presents a new, distributed location management strategy for mobile systems. Its features are fast location update and query, load balancing among location servers, and scalability. The strategy employs dynamic hashing techniques and...
Show moreLocation management in a mobile network provides functions to locate, identify, and validate a terminal or user. The purpose of this thesis is to describe a scheme that would be useful in a wireless network for managing the location of mobile users. This thesis presents a new, distributed location management strategy for mobile systems. Its features are fast location update and query, load balancing among location servers, and scalability. The strategy employs dynamic hashing techniques and quorums to manage location update and query operations. Location information of a mobile host is replicated at a subset of location servers.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12712
- Subject Headings
- Mobile communication systems, Mobile computing
- Format
- Document (PDF)
- Title
- Indoor Localization using WiFi Wireless LANs.
- Creator
- Azandaryani, Saeid Mirzaei, Cardei, Ionut E., Graduate College
- Date Issued
- 2013-04-12
- PURL
- http://purl.flvc.org/fcla/dt/3361902
- Subject Headings
- Wireless LANs, Mobile communication systems
- Format
- Document (PDF)
- Title
- Virtualization techniques for mobile systems.
- Creator
- Jaramillo, David, Furht, Borko, Agarwal, Ankur, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In current mobile system environment there is a large gap in the use of smart phones for personal and enterprise use due to required enterprise security policies, privacy concerns as well as freedom of use. In the current environment, data-plans on mobile systems have become so wide spread that the rate of adaptation of data plans for every day customers has far outpaced the ability for enterprises to keep up with existing secure enterprise infrastructures. Most of the enterprises require...
Show moreIn current mobile system environment there is a large gap in the use of smart phones for personal and enterprise use due to required enterprise security policies, privacy concerns as well as freedom of use. In the current environment, data-plans on mobile systems have become so wide spread that the rate of adaptation of data plans for every day customers has far outpaced the ability for enterprises to keep up with existing secure enterprise infrastructures. Most of the enterprises require/provide the access of emails and other official information on smart platforms which presents a big challenge for the enterprise in securing their systems. Therefore due to the security issues and policies imposed by the enterprise in using the same device for dual purpose (personal and enterprise), the consumers often lose their individual freedom and convenience at the cost of security. Few solutions have been successful addressing this challenge. One effective way is to partition the mobile device such that the enterprise system access and its information are completely separated from the personal information. Several approaches are described and presented for mobile virtualization that creates a secure and secluded environment for enterprise information while allowing the user to access their personal information. A reference architecture is then presented that allows for integration with existing enterprise mobile device management systems and at the same time providing a light weight solution for containerizing mobile applications. This solution is then benchmarked with several of the existing mobile virtualization solutions.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004028
- Subject Headings
- Mobile communication systems, Virtual computer systems
- Format
- Document (PDF)
- Title
- Diversity performance of DS-CDMA systems in multipath fading channels.
- Creator
- Efthymoglou, George P., Florida Atlantic University, Helmken, Henry, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In this dissertation, new semi-analytical expressions for the diversity bit error rate performance of asynchronous direct sequence-code division multiple access (DS-CDMA) systems in multipath fading channels are derived. Also, the PN acquisition time of a DS system with offset frequency periods greater than the code period in a AWGN channel is measured via laboratory experiments. In Part I we consider DS-CDMA systems operating in a cellular environment with multipath reception. Multipath...
Show moreIn this dissertation, new semi-analytical expressions for the diversity bit error rate performance of asynchronous direct sequence-code division multiple access (DS-CDMA) systems in multipath fading channels are derived. Also, the PN acquisition time of a DS system with offset frequency periods greater than the code period in a AWGN channel is measured via laboratory experiments. In Part I we consider DS-CDMA systems operating in a cellular environment with multipath reception. Multipath propagation is exploited through the use of RAKE receivers. Coherent, differentially coherent and noncoherent binary demodulation schemes are considered. The multiple access interference is modeled as AWGN, conditioned on the fading statistics of the received signal. The mobile radio channel introduces selective fading, and is modeled as a tapped delay line. The amplitude of each resolvable path is statistically described by the Nakagami distribution, which is a general solution to the random vector problem that causes rapid fading. However, we assume independent but nonidentical fading along the RAKE branches. Therefore our analysis supports unequal mean powers and different amount of fading in the multipath components combined by the receiver. Also, the results can be easily extended to account for diversity from multiple antennas or coding in the generalized Nakagami multipath fading environment. In Part II we consider a land mobile satellite channel. First, a laboratory experiment is setup to evaluate the PN acquisition performance of a digital IF receiver in a AWGN channel with large Doppler offset. The digital conversion receiver uses the inherent aliasing property of sampling to realize the baseband conversion using a single analog-to-digital converter. Thereafter, digital signal processing on the I and Q samples enable for design trade-offs in the acquisition of the PN code with Doppler periods greater than the code period. Two code phase selection criterions, namely the maximum criterion and the threshold crossing criterion, are investigated and their acquisition time is measured for different frequency offsets and input IF signal to noise ratios. We also derive semi-analytical expressions for the BER performance of coherent and differentially coherent systems operating in a mobile satellite channel. In this case the channel is modeled as a multipath nonselective channel, but diversity gain can still be obtained through path diversity. This is the scenario when a signal is transmitted to all satellites in view and the received replicas are independently demodulated and combined at the receiver. Our analysis extends previous results to the case of unequal mean powers and Rice factors in the combined signals; a valid assumption if we consider that the satellites are in view at different elevation angles. Furthermore, the effect of imperfect power control in such mobile satellite DS-CDMA systems is also considered.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/12516
- Subject Headings
- Mobile communication systems, Wireless communication systems, Radio wave propagation
- Format
- Document (PDF)
- Title
- Performance of wireless communication systems under various data traffic density distributions.
- Creator
- Kyperountas, Spyros C., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis is concerned with the performance analysis of mobile cellular systems under various distributions of portable users. The performance measure used is the average outage probability. Performance analysis is performed for macrocellular as well as microcellular systems, for different distributions of mobile users such as uniform, ring, and bell distribution. The outage probability is evaluated for systems with hexagonal, triangular, and square grid layouts. The effect of macroscopic...
Show moreThis thesis is concerned with the performance analysis of mobile cellular systems under various distributions of portable users. The performance measure used is the average outage probability. Performance analysis is performed for macrocellular as well as microcellular systems, for different distributions of mobile users such as uniform, ring, and bell distribution. The outage probability is evaluated for systems with hexagonal, triangular, and square grid layouts. The effect of macroscopic diversity on system performance is also considered. Finally, computer simulations are used to verify the evaluated results.
Show less - Date Issued
- 1998
- PURL
- http://purl.flvc.org/fcla/dt/15578
- Subject Headings
- Wireless communication systems, Cellular radio, Mobile communication systems
- Format
- Document (PDF)
- Title
- Performance analysis of RLP for NAK based ARQ scheme in cdma2000 wireless systems for random error channels.
- Creator
- Easo, Daniel J., Florida Atlantic University, Pandya, Abhijit S.
- Abstract/Description
-
This thesis is an effort to present the performance analysis of the RLP in cdma2000, which uses the NAK based ARQ scheme for Random Error Channels. The performance analyses is done in terms of throughput and mean extra delay, which are calculated analytically and are compared with the results generated from the simulations. As the demand for higher data rates increases over the wireless channels, this thesis studies the effect of the random errors over the different types of RLP frame formats...
Show moreThis thesis is an effort to present the performance analysis of the RLP in cdma2000, which uses the NAK based ARQ scheme for Random Error Channels. The performance analyses is done in terms of throughput and mean extra delay, which are calculated analytically and are compared with the results generated from the simulations. As the demand for higher data rates increases over the wireless channels, this thesis studies the effect of the random errors over the different types of RLP frame formats and also the performance of the NAK based ARQ mechanism used in these conditions. The simulation provides with the overall characteristics of the throughput and the mean extra delay in terms of realistic environment parameters like Eb/No and probability of packet error (Pe), based on the channel conditions.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12810
- Subject Headings
- Code division multiple access, Wireless communication systems, Mobile communication systems
- Format
- Document (PDF)
- Title
- Indexed resource auction multiple access (I-RAMA): A new medium access scheme for third generation wireless networks.
- Creator
- Barrantes-Sliesarieva, Elena Gabriela., Florida Atlantic University, Ulyas, Mohammad
- Abstract/Description
-
Indexed Resource Auction Multiple Access (I-RAMA), a new medium access protocol for wireless cellular networks based on Resource Auction Multiple Access (RAMA) is presented. I-RAMA relies in variable length resource auctions, whose length depends on the time it takes the Base Station to uniquely identify the Mobile Station. This identification is done by using dynamic Base Station information about the users present in the cell at any moment. I-RAMA effectively reduces the amount of time...
Show moreIndexed Resource Auction Multiple Access (I-RAMA), a new medium access protocol for wireless cellular networks based on Resource Auction Multiple Access (RAMA) is presented. I-RAMA relies in variable length resource auctions, whose length depends on the time it takes the Base Station to uniquely identify the Mobile Station. This identification is done by using dynamic Base Station information about the users present in the cell at any moment. I-RAMA effectively reduces the amount of time spent in the resource auctions without introducing contention or excessive complexity at the Base Station. The effects of introducing data users in the system are investigated using a simulation, and it is shown that I-RAMA guarantees Quality of Service for isochronous users while maintaining a bounded delay for data users at much higher loads than RAMA.
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/15204
- Subject Headings
- Wireless communication systems, Cellular radio, Mobile communication systems, Computer algorithms
- Format
- Document (PDF)
- Title
- Information-theoretics based analysis of hard handoffs in mobile communications.
- Creator
- Bendett, Raymond Morris., Florida Atlantic University, Neelakanta, Perambur S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The research proposed and elaborated in this dissertation is concerned with the development of new decision algorithms for hard handoff strategies in mobile communication systems. Specifically, the research tasks envisaged include the following: (1) Use of information-theoretics based statistical distance measures as a metric for hard handoff decisions; (2) A study to evaluate the log-likelihood criterion towards decision considerations to perform the hard handoff; (3) Development of a...
Show moreThe research proposed and elaborated in this dissertation is concerned with the development of new decision algorithms for hard handoff strategies in mobile communication systems. Specifically, the research tasks envisaged include the following: (1) Use of information-theoretics based statistical distance measures as a metric for hard handoff decisions; (2) A study to evaluate the log-likelihood criterion towards decision considerations to perform the hard handoff; (3) Development of a statistical model to evaluate optimum instants of measurements of the metric used for hard handoff decision. The aforesaid objectives refer to a practical scenario in which a mobile station (MS) traveling away from a serving base station (BS-I) may suffer communications impairment due to interference and shadowing affects, especially in an urban environment. As a result, it will seek to switch over to another base station (BS-II) that facilitates a stronger signal level. This is called handoff procedure. (The hard handoff refers to the specific case in which only one base station serves the mobile at the instant of handover). Classically, the handoff decision is done on the basis of the difference between received signal strengths (RSS) from BS-I and BS-II. The algorithms developed here, in contrast, stipulate the decision criterion set by the statistical divergence and/or log-likelihood ratio that exists between the received signals. The purpose of the present study is to evaluate the relative efficacy of the conventional and proposed algorithms in reference to: (i) Minimization of unnecessary handoffs ("ping-pongs"); (ii) Minimization of delay in handing over; (iii) Ease of implementation and (iv) Minimization of possible call dropouts due to ineffective handover envisaged. Simulated results with data commensurate with practical considerations are furnished and discussed. Background literature is presented in the introductory chapter and scope for future work is identified via open questions in the concluding chapter.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12639
- Subject Headings
- Mobile communication systems, Information theory, Algorithms
- Format
- Document (PDF)
- Title
- Mobility pattern-based routing algorithm for mobile ad hoc wireless networks.
- Creator
- Vyas, Nirav., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm...
Show moreThis thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm to reduce the overhead, then evaluate the proposed algorithm through simulation. We have implemented two mobility patterns into Location Aided Routing, namely, leading movement and random walk type mobility patterns. We have developed simulation model for each mobility pattern, using SES/Workbench. The performance is measured in terms of overhead of the network. We also discuss various routing algorithms such as dynamic source routing, zone routing protocol, associativity based routing protocol and ad hoc on demand distance vector routing.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12662
- Subject Headings
- Mobile computing, Wireless communication systems, Computer algorithms
- 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.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12703
- Subject Headings
- Mobile computing, Computer networks, Wireless communication systems
- Format
- Document (PDF)
- Title
- Remote gaming on resource constrained devices.
- Creator
- Reza, Waazim., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Games have become important applications on mobile devices. A mobile gaming approach known as remote gaming is being developed to support games on low cost mobile devices. In the remote gaming approach, the responsibility of rendering a game and advancing the game play is put on remote servers instead of the resource constrained mobile devices. The games rendered on the servers are encoded as video and streamed to mobile devices. Mobile devices gather user input and stream the commands back...
Show moreGames have become important applications on mobile devices. A mobile gaming approach known as remote gaming is being developed to support games on low cost mobile devices. In the remote gaming approach, the responsibility of rendering a game and advancing the game play is put on remote servers instead of the resource constrained mobile devices. The games rendered on the servers are encoded as video and streamed to mobile devices. Mobile devices gather user input and stream the commands back to the servers to advance game play. With this solution, mobile devices with video playback and network connectivity can become game consoles. In this thesis, we present the design and development of such a system and evaluate the performance and design considerations to maximize the end user gaming experience. A gaming user experience model capable of predicting the user experience for a given gaming session is developed and verified.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2978944
- Subject Headings
- Wireless communication systems, Mobile communication systems, Mobie computing, Programming, Application software, Development, Game theory, Mobile commerce
- Format
- Document (PDF)
- Title
- Performance analysis of mobile LEO satellite cellular systems.
- Creator
- Alwakeel, Mohammed., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This dissertation is concerned with studies on the performance aspects of mobile LEO satellite cellular systems. Relevant performance measures studied in the dissertation include new call blocking probability, handoff failure probability, call termination probability, and call dropping probability. The analytical teletraffic models available in the literature are generalized in this work in order to characterize the 3G systems more realistically. The effect of earth rotation on cell residence...
Show moreThis dissertation is concerned with studies on the performance aspects of mobile LEO satellite cellular systems. Relevant performance measures studied in the dissertation include new call blocking probability, handoff failure probability, call termination probability, and call dropping probability. The analytical teletraffic models available in the literature are generalized in this work in order to characterize the 3G systems more realistically. The effect of earth rotation on cell residence time is also investigated and a new cell residence time model is developed. The new model proposed uses right-truncated gamma distribution to describe the statistics of residence time in the origination cell; and, the generalized beta distribution is used to model the residence time in subsequent cells. A closed-form expression to determine the premature call termination and call dropping probabilities is proposed. The proposed expression requires only the cumulative distribution function of the call holding time and the first four moments of the cell residence time. In all the above probabilistic considerations, the arrival process is regarded as: (i) Poissonian implying voice-like traffic and (ii) non-Poissonian depicting inhomogeneous mix of voice, data, and video transmissions expected on a trunk traffic. The effect of factors that may affect the signal intensity on the performance of mobile LEO satellite cellular systems is also investigated. In particular, a mathematically tractable expression to approximate the moments of cell residence time in origination cell as well as in subsequent cells is developed based on the received signal power.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/12132
- Subject Headings
- Wireless communication systems, Personal communication service systems, Artificial satellites in telecommunication, Mobile communication systems
- Format
- Document (PDF)
- Title
- Simulation-based performance evaluation of packet-switched H.264/AVC video streaming on WCDMA networks.
- Creator
- Murillo, Carlos A., Florida Atlantic University, Iskander, Cyril-Daniel, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis presents the simulation based performance evaluation on the transmission of multimedia services (H.264/AVC video streaming) to a mobile user over a packet-switched wireless network based on the WCDMA standard. The H.264/AVC refers to the codec, which is used as the main tool for video compression. It enables the transport of high bandwidth video data over Third Generation (3G) wireless systems by offering a high video compression rate, adaptability to the channel, and error...
Show moreThis thesis presents the simulation based performance evaluation on the transmission of multimedia services (H.264/AVC video streaming) to a mobile user over a packet-switched wireless network based on the WCDMA standard. The H.264/AVC refers to the codec, which is used as the main tool for video compression. It enables the transport of high bandwidth video data over Third Generation (3G) wireless systems by offering a high video compression rate, adaptability to the channel, and error resilience. It is transported using the RTP/UDP/IP protocol stack over the 3G wireless system. The WCDMA technology is simulated with special emphasis on the upper layers of the wireless channel. The performance of the WCDMA system is studied when transporting RTP/UDP/IP packets of H.264/AVC compressed video data under diverse configuration scenarios, namely, ARQ schemes and variable length of the transmitted frame at the link layer. These components of a packet-switched streaming service are integrated into a software simulation model, which is used to evaluate the end-to-end H.264/AVC video quality in a WCDMA wireless network.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13291
- Subject Headings
- Wireless communication systems, Mobile communication systems, Global system for mobile communications, Code division multiple access, Streaming technology (Telecommunications)
- Format
- Document (PDF)
- Title
- Simulation study of reservation scheme to improve the quality of service in wireless cellular network.
- Creator
- Chokshi, Patheek G., Florida Atlantic University, Ilyas, Mohammad
- Abstract/Description
-
In the present computer age, cellular technology and portable computers are becoming an integral part of the life. Each computer user wants to access the computing resources, irrespective of the location. Because of this need the computing paradigm "Mobile Computing" has assumed a primary role in modern computer communication technology. While dimensioning the network resources, it is very important to know how the users move around the geographical area covered by the cellular network. This...
Show moreIn the present computer age, cellular technology and portable computers are becoming an integral part of the life. Each computer user wants to access the computing resources, irrespective of the location. Because of this need the computing paradigm "Mobile Computing" has assumed a primary role in modern computer communication technology. While dimensioning the network resources, it is very important to know how the users move around the geographical area covered by the cellular network. This knowledge allows us to plan the system resources in order to achieve the QoS required. The major factors that affect the performance, along with the mobility pattern of the mobile user, are the speed at which the user is moving and the load on the network. In this research, we study different types of mobility patterns the user can follow and it's impact on the network services. We have proposed and evaluated a reservation scheme to improve the QoS in the cellular network. The reservation scheme reserves some part of the bandwidth for handoff connections. We have developed simulation programs and have studied three mobility patterns namely leading movement type, random motion, and square-street mobility pattern for measuring the QoS for cellular network. It has been observed from the results that at an average speed of 50 miles per hour with the average loading of the network, a significant improvement in QoS has been achieved for all the mobility patterns by using the reservation scheme.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15706
- Subject Headings
- Wireless communication systems, Mobile computing, Cellular telephone systems
- Format
- Document (PDF)
- Title
- A improved video codec supporting error resilience and resource adaptation.
- Creator
- Furht, Borko, Sanigepalli, Praveen, Kalva, Hari
- Date Issued
- 2005-01-8 - 2005-01-12
- PURL
- http://purl.flvc.org/fcla/dt/351015
- Subject Headings
- MPEG (Video coding standard), Digital video., Mobile 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.
Show less - 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
- Integrated platform for coordination of emergency medical response system using mobile devices.
- Creator
- Chakrabarty, Nabarun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis presents a framework for a platform that integrates various infrastructural services and facilities in an automated manner to improve and coordinate the processes of medical emergency response system (MERS). It aims to improve the quality of healthcare system infrastructure by improving the quality of service of MERS. Presently the processes of MERS and their coordination are semi-automated, which adds to the complication of service availability and information exchange among...
Show moreThis thesis presents a framework for a platform that integrates various infrastructural services and facilities in an automated manner to improve and coordinate the processes of medical emergency response system (MERS). It aims to improve the quality of healthcare system infrastructure by improving the quality of service of MERS. Presently the processes of MERS and their coordination are semi-automated, which adds to the complication of service availability and information exchange among participating systems, thereby affecting the MERS' quality of service adversely. An integrated platform for the coordination of MERS processes can help improve its quality of service and ensure better control of data and process flow. The improvements to the MERS service quality can significantly contribute to the improvement of the quality of healthcare infrastructure. The integrated platform framework presented here resolves the problems of data flow and process coordination to achieve the desired goal.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/1927611
- Subject Headings
- Mobile communication systems, Radio paging, Health services accessibility
- Format
- Document (PDF)
- Title
- Key management in mobile ad hoc networks.
- Creator
- Wu, Bing., Florida Atlantic University, Wu, Jie, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In mobile ad hoc networks (MANETs), providing secure communications is a big challenge due to unreliable wireless media, host mobility and lack of infrastructure. Usually, cryptographic techniques are used for secure communications in wired networks. Symmetric and asymmetric cryptography have their advantages and disadvantages. In fact, any cryptographic means is ineffective if its key management is weak. Key management is also a central aspect for security in mobile ad hoc networks. In...
Show moreIn mobile ad hoc networks (MANETs), providing secure communications is a big challenge due to unreliable wireless media, host mobility and lack of infrastructure. Usually, cryptographic techniques are used for secure communications in wired networks. Symmetric and asymmetric cryptography have their advantages and disadvantages. In fact, any cryptographic means is ineffective if its key management is weak. Key management is also a central aspect for security in mobile ad hoc networks. In MANETs, the computational load and complexity for key management are strongly subject to restriction by the node's available resources and the dynamic nature of network topology. We proposed a secure and efficient key management framework (SEKM) for MANETs. SEKM builds a PKI by applying a secret sharing scheme and using an underlying multicast server groups. In SEKM, each server group creates a view of the certificate authority (CA) and provides certificate update service for all nodes, including the servers themselves. Motivated by the distributed key management service, we introduced k-Anycast concept and proposed three k-anycast routing schemes for MANETs. k-anycast is proposed to deliver a packet to any threshold k members of a set of hosts. Our goal is to reduce the routing control messages and network delay to reach any k servers. The first scheme is called controlled flooding. The second scheme, called component-based scheme I, is to form multiple components such that each component has at least k members. The third scheme, called component-based scheme II, in which the membership a component maintains is relaxed to be less than k. Collaborative and group-oriented applications in MANETs is an active research area. Group key management is a central building block in securing group communications in MANETs. However, group key management for large and dynamic groups in MANETs is a difficult problem. We propose a simple and efficient group key management scheme that we named SEGK for MANETs, which is based on n-party Diffie-Hellman (DH). The basic idea of our scheme is that a physical multicast tree is formed in MANETs for efficiency. To achieve fault tolerance, double multicast trees are constructed and maintained. A group coordinator computes and distributes intermediate keying materials to all members through multicast tree links. All group members take turns acting as group coordinator and distributing the workload of group rekeying during any change of group membership. Every group member computes the group key in a distributed manner.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/12234
- Subject Headings
- Electronic commerce--Technological innovations, Mobile commerce--Technological innovations, Wireless communication systems--Management, Mobile communication systems--Management
- Format
- Document (PDF)
- Title
- A Phased Approach to Evaluate the Performance of Handoff by Mobile Handsets.
- Creator
- Siddiqui, Arjumand Fatima, Pandya, Abhijit S., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The ever increasing demand for capacity in wireless cellular networks is resolved by decreasing the size of the cells. The smaller cells created inside large cells are called microcells and they cover smaller and dense areas. As a result of this, the mobile device ends up changing the base stations or performing handover at a much higher rate. To maintain the reliability and quality of the call, it is obligatory to ascertain that the handover is performed at a proper location. If the handover...
Show moreThe ever increasing demand for capacity in wireless cellular networks is resolved by decreasing the size of the cells. The smaller cells created inside large cells are called microcells and they cover smaller and dense areas. As a result of this, the mobile device ends up changing the base stations or performing handover at a much higher rate. To maintain the reliability and quality of the call, it is obligatory to ascertain that the handover is performed at a proper location. If the handover is delayed or the mobile handset drags its base station, it is more probable that either the call will drop or the quality of the call will be compromised. The last thing a mobile handset user would want is to experience any of these two consequences. In this thesis we study the methods to analyze the performance ofhandover by the mobile handsets in the drive setup under test. This thesis presents a model for analyzing the performance ofhandoffbased on the measurements ofthe received signal strength indicator and the color code recorded by the mobile handset in the drive test field path. The model from the simulations is seen to yield results that agree with other research about the performance of mobile handsets.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00012551
- Subject Headings
- Mobile communication systems--Design, Wireless communication systems--Technological innovations, Cellular telephones--Design
- Format
- Document (PDF)
- Title
- Studies on performance aspects of smart wireless devices and related network services.
- Creator
- Noori, Aziz Ulhaq, Neelakanta, Perambur S., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This study is a focused effort on elucidating the performance aspects of modern, handheld wireless devices and associated mobile network services. Specifically addressed thereof are: (i) Assessing the performance details on certain hardware sections of smart handheld devices and (ii) determining the performance profile of market penetration considerations vis-à-vis provisioning mobile networks. To meet the scope of this research, the projected efforts are exercised in compiling relevant...
Show moreThis study is a focused effort on elucidating the performance aspects of modern, handheld wireless devices and associated mobile network services. Specifically addressed thereof are: (i) Assessing the performance details on certain hardware sections of smart handheld devices and (ii) determining the performance profile of market penetration considerations vis-à-vis provisioning mobile networks. To meet the scope of this research, the projected efforts are exercised in compiling relevant literature and deciding the said hardware and technoeconomic performance issues. Hence, written in two parts, Part A is devoted to hardware performance details of smart, handheld devices relevant to (a) delay issues in PCB layouts; (b) crosstalk problems at the baseband level (audio/multimedia) using EMI concepts and (c) ascertaining non-catastrophic EMP/EMI effects at the RF-sections so as to implement protection strategies via compensating networks. Part B is concerned with the technoeconomics of wireless networks in supporting mobile (handheld devices). Correspondingly, two market related considerations versus service performance details are considered. The first one refers to deducing a relative performance index that includes technology (mobile speed) details plus economics profiles of the users in the service area. The second task refers to elucidating a performance index of such services in terms of hedonic pricing heuristics. The theoretical aspects of the test studies as above are supplemented with experimental and/or simulation details as appropriate. Hence, the efficacy of performance details are discussed in real-world applications. Lastly, possible research items for future studies are identified as open-questions.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004395, http://purl.flvc.org/fau/fd/FA00004395
- Subject Headings
- Mobile communication systems -- Standards, Network performance (Telecommunications), Smartphones, Technoeconomcs, Wireless communication systems -- Technological innovations
- Format
- Document (PDF)
