Dissertations / Theses: 'Wireless LANs'

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Grape, Torbjörn. "Wireless LANs, Real-Time Traffic." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1794.

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The usage of Wireless Local Area Networks is increasing rapidly throughout the world. The technology today is not quality proof for the market’s demands. We want to be able to completely wireless perform our demands, such as confer via video or IP-telephony. This is what we call multimedia real-time traffic. It may be achieved over the physical infrastructure in some areas with good results. The goal of this Master’s Thesis is to analyze the possibilities and give solutions and suggestions to achieve multimedia over the wireless networks, with emphasis on the protocol Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA).

This Master’s Thesis is a theoretical study and the suggested solutions have not been tested in an actual wireless network. Instead they have been tested by computer simulation to give an indication of improvements. Basic configurations are set to the same as in the IEEE 802.11 standard.

Different methods to reach possible improvements of a WLAN are studied, analyzed and simulated. Such methods are: priority, congestion management and multi-channel protocol. Simulations results show how the priority affects the wireless network and how a multi-channel protocol improves the latency and efficiency of the network. The simulation part is concentrated to show improvements of real-time traffic, which is time sensitive. With a multi- channel protocol the network can allow more users, i.e. more traffic. Also, the network will gain improvement in stability.

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Ross, David Andrew. "Securing IEEE 802.11 wireless LANs." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/37638/1/David_Ross_Thesis.pdf.

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As the acceptance and popularity of wireless networking technologies has proliferated, the security of the IEEE 802.11 wireless local area network (WLAN) has advanced in leaps and bounds. From tenuous beginnings, where the only safe way to deploy a WLAN was to assume it was hostile and employ higherlayer information security controls, to the current state of the art, all manner of improvements have been conceived and many implemented. This work investigates some of the remaining issues surrounding IEEE 802.11 WLAN operation. While the inherent issues in WLAN deployments and the problems of the original Wired Equivalent Privacy (WEP) provisions are well known and widely documented, there still exist a number of unresolved security issues. These include the security of management and control frames and the data link layer protocols themselves. This research introduces a novel proposal to enhance security at the link layer of IEEE 802.11 WLANs and then conducts detailed theoretical and empirical investigation and analysis of the eects of such proposals. This thesis �rst de�nes the state of the art in WLAN technology and deployment, including an overview of the current and emerging standards, the various threats, numerous vulnerabilities and current exploits. The IEEE 802.11i MAC security enhancements are discussed in detail, along with the likely outcomes of the IEEE 802.11 Task Group W1, looking into protected management frames. The problems of the remaining unprotected management frames, the unprotected control frames and the unprotected link layer headers are reviewed and a solution is hypothesised, to encrypt the entire MAC Protocol Data Unit (MPDU), including the MAC headers, not just the MAC Service Data Unit (MSDU) commonly performed by existing protocols. The proposal is not just to encrypt a copy of the headers while still using cleartext addresses to deliver the frame, as used by some existing protocols to support the integrity and authenticity of the headers, but to pass the entire MPDU only as ciphertext to also support the con�dentiality of the frame header information. This necessitates the decryption of every received frame using every available key before a station can determine if it is the intended recipient. As such, this raises serious concerns as to the viability of any such proposal due to the likely impact on throughput and scalability. The bulk of the research investigates the impacts of such proposals on the current WLAN protocols. Some possible variations to the proposal are also provided to enhance both utility and speed. The viability this proposal with respect to the eect on network throughput is then tested using a well known and respected network simulation tool, along with a number of analysis tools developed speci�cally for the data generated here. The simulator's operation is �rst validated against recognised test outputs, before a comprehensive set of control data is established, and then the proposal is tested and and compared against the controls. This detailed analysis of the various simulations should be of bene�t to other researchers who need to validate simulation results. The analysis of these tests indicate areas of immediate improvement and so the protocols are adjusted and a further series of experiments conducted. These �nal results are again analysed in detail and �nal appraisals provided.

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Lin, Xiaoyang. "Improving fairness in the 802.11 infrastructure wireless local area networks /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?COMP%202005%20LIN.

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Tay, Chye Bin. "Wireless LAN extension." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Mar%5FTay.pdf.

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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, March 2003.
Thesis advisor(s): Norman F. Schneidewind, Douglas E. Brinkley. Includes bibliographical references (p. 67). Also available online.

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Ozturk, Huseyin Selcuk. "Evaluation of secure 802.1X port-based network access authentication over 802.11 wireless local area networks." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Mar%5FOzturk.pdf.

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Sattari, Afsaneh. "An experimental study of wireless LANs." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27420.

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Wireless equipment based on IEEE 802.11 standard has been increasingly successful during the recent years. The popularity of wireless LAN hardware, and increasing use of different applications has brought challenges and competition among different vendors of IEEE 802.11 standards. Traditionally, such equipment has mainly been used indoors to allow users to wirelessly connect to the Internet or to a LAN. In this thesis we evaluate wireless equipment of the 802.11b standard. We consider typical scenarios and also consider typical transport protocols (i.e. TCP and UDP) in order to observe the performance of the system in real settings. Although the performance of a system mainly depends on the following metrics: throughput, packet loss, delay and jitter, in this thesis we take into consideration a large number of metrics of performance in order to obtain a better understanding of the way diverse factors impact performance in real wireless LANs. Indeed, we perform a large set of tests and measurements with different hardware. This let us obtain a more complete view of the performance of the system. Such parameters are important in real networks since its interrelation affect the quality of service perceived by various services carried by the network. We observe that real throughput of WLANs is sensibly lower than the raw amount usually advertised by the manufacturers. From the obtained results we conclude that in addition to the lack of efficiency of the MAC layer, this situation is also due to the combination of other factors that are detailed in the thesis. We found that one of the most important factor affecting the performance is a corner in the signal path between the sender and the receiver, which significantly affects the performance. We also describe some different hardware and software tools that are useful to carry out the tasks required for a performance study in a wireless LAN.

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Oudit, Suzanne Riggs Lloyd Stephen. "Design of an outdoor wireless local area network and antenna analysis." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/OUDIT_SUZANNE_45.pdf.

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Ozyagci, Ali. "Capacity analysis of densely deployed wireless LANs." Doctoral thesis, KTH, Radio Systems Laboratory (RS Lab), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-154343.

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Wireless LANs (WLANs) based on the IEEE 802.11 standard have become an integral part of today’s indoor wireless communication infrastructure. As WLAN deployments become more prevalent and densely deployed, the nodes in these WLANs start to create congestion and interference with each other. This congestion and interference fundamentally limits the performance of these coexisting WLANs. We analyze the capacity limits of such densely deployed WLANs. We begin our analysis by investigating the suitability of the attributes of WLANs, namely their cooperative operation based on locally available information, for indoor high-capacity wireless access provisioning. We compare the cooperative class of wireless systems with another class of systems whose users behave selfishly. Following this qualitative assessment, we perform a detailed, qualitative analysis of the capacity of densely deployed WLANs in terms of a number of key environmental and operational parameters. The indoor propagation environment has a significant influence on the congestion and interference that these coexisting WLANs exert on each other. Therefore we investigate the impact of propagation environment on the aggregate throughput of densely deployed WLANs. As WLANs are deployed in close proximity of each other, the transmissions in one WLAN start to influence the outcome of transmissions in other WLANs. The manner in which the access points are deployed, and the manner in which stations associate themselves with the available access points around themselves is shown to be an influential factor in the performance of these coexisting WLANs. Therefore, we investigate the impact of random versus planned access point deployment on performance of densely deployed WLANs. Similarly, we investigate the impact of stations associating with the access point with the strongest signal or with another sufficiently strong access point in their vicinity. Furthermore, we investigate the throughput of densely deployed WLANs when operating with bounded delay. More specifically we examine the case when the input traffic arriving at the transmitters are expected to reach their destination within a certain time period, thus the transmit queues cannot grow without bounded and the system should operate at a stable point. The indoor propagation environment, creates complex interference relationships between nodes in coexisting WLANs.These complex interference relationships are compounded by the node interactions dictated by the nonlinear algorithms in the IEEE 802.11 MAC protocol, thus the problem of estimating the performance of these coexisting WLANs by means of simple analytical models becomes difficult. In contrast, detailed packet level simulations provide accurate performance estimates, although such analyses are computationally expensive. Therefore we seek to provide a model to estimate the throughput of densely deployed WLANs based on empirical throughput results of detailed simulations of such densely deployed WLANs. In addition, in our effort to develop an empirical throughput model for densely deployed WLANs, we develop a measure which we call “cell congestion” to be able to order and compare different propagation environments, and an “effective density” concept which accounts for the influence of the propagation environment on the congestion and interference experienced by a WLAN deployment of a given density. We expect these concepts to be useful in improving the operation of WLANs to be able to meet the predicted increase in demand for capacity.

QC 20141020

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Xi, Weihua. "MAC enhancements for high speed wireless LANs." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446178.

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Ren, Shaolei. "Cooperative wireless networks with QoS guarantees /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20REN.

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Fountanas, Leonidas. "An assessment of emerging wireless broadband technologies." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA401101.

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Thesis (M.S. in Computer Science) Naval Postgraduate School, Dec. 2001.
"December 2001." Thesis advisor(s): Bert Lundy. Cover title: An assessment of emerging wireless broadband technolofies. Includes bibliographical references (p. 73-75). Also available online.

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Goh, Che Seng. "Prototype system for detecting and processing of IEEE 802.11a signals." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FGoh.pdf.

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Nyandoro, Alfandika Computer Science &amp Engineering Faculty of Engineering UNSW. "Utilising power capture for service differentiation in wireless LANs." Awarded by:University of New South Wales. School of Computer Science and Engineering, 2006. http://handle.unsw.edu.au/1959.4/24946.

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In recent years, wireless communication systems have become pervasive, allowing continuous connectivity for people on the move, at home and in the workplace. The advent of third generation (3G) systems with capabilities beyond traditional telephony, and the explosive uptake of wireless Local Area Networks (LANs) are but two factors that have contributed to this growth. By virtue of their appeal to the market, wireless LANs have proven to be a serious contender as the access technology of choice for traditional data as well as the emerging 3G networks. If wireless LANs are to be successful as an access technology, however, the issue of Quality of Service (QoS) support will need to be addressed. QoS support for wireless LANs is becoming increasingly important because applications requiring such support, e.g. voice and video, are becoming more common in today's hybrid wireless systems, with the trend expected to grow into the future. The dominant standard for wireless LANs is the IEEE's 802.11 of which the contention-based Medium Access Control (MAC) protocol; also known as the Distributed Coordination Function (DCF), is universally supported. While the DCF is widely supported, it provides no QoS support. In this work, we propose and study a new and different mechanism of achieving service differentiation in 802.11 wireless LANs. Our approach employs the capture effect as the vehicle for achieving QoS differentiation for the contention mode of the standard. This approach enriches current research efforts by providing another dimension to QoS provisioning in wireless LANs. Hitherto most proposals have focussed on the modification of some aspect of the protocol, such as the minimum contention window size (CWmin), the Distributed Inter-Frame Space (DIFS), or the maximum contention window size (CWmax), amongst others. Capture based service differentiation complements these efforts. It can be used alone or in conjunction with existing approaches to provide additional priority classes. In this thesis, the capture based service differentiation approach is proposed and studied through Markov chain modelling and simulation. From the study, the following conclusions were drawn. It was confirmed that capture based service differentiation is a feasible approach in wireless LANs and that it can be achieved with practical and sustainable power differences between the transmitters from different classes. A number of factors were found to influence the level of service differentiation, including the population ratios of hosts in the power classes, the power ratios of the transmitters as well as the capture threshold of the receiver. For practical considerations, a complete architectural framework is also proposed, including support functions such as Transmission Power Control (TPC), QoS Signalling and Admission Control.

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CHINTALA, VENKATA MANOJ. "HANDOFF SCHEMES FOR THE IEEE 802.11 WIRELESS LANs." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1177969593.

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Ashraf, Parvez M. "Capacity maximizing design for 802.11 based wireless LANs." Ann Arbor, Mich. : ProQuest, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1447244.

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Thesis (M.S. in Electrical Engineering)--S.M.U., 2007.
Title from PDF title page (viewed Nov. 19, 2009). Source: Masters Abstracts International, Volume: 46-03, page: 1644. Adviser: Dinesh Rajan. Includes bibliographical references.

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Lian, Jason Hailin. "An improved media access control protocol for wireless LANs a thesis submitted to Auckland University of Technology in partial fulfilment of the requirements of the degree of Master of Information Technology, 2004." Full thesis. Abstract, 2004.

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Abdul, Halim Syafnidar. "Exploring wireless network security in Auckland City through warwalking a dissertation submitted to Auckland University of Technology in partial fulfillment of the requirements for the degree of Master of Computer and Information Sciences (MCIS), 2007." Abstract. Full dissertation, 2007.

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Yeung, Man Chung. "Wireless LAN positioning in indoor environment." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/942.

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Aggarwal, Pankaj. "Mobile authentication in wireless systems." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010839.

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Chen, Xiang. "Resource management in wireless networks." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011549.

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Roman, Alexandru Bogdan. "Scalable cross-layer wireless medium access control." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609506.

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Kriara, Lito. "Holistic and efficient link adaptation for 802.11x wireless LANs." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/15871.

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Wireless LANs (WLANs), based on the IEEE 802.11 standard, have become the standard means for indoor wireless connectivity. At the same time, the rising number of smart mobile devices, broadband access speeds, and bandwidth hungry applications (e.g., high definition video streaming) have led to an increase not only of usage but also of demand for higher data-rates. This demand for higher rates is being met with newer IEEE 802.11 standards (e.g., 802.11n/ac) that introduce new features and also increase the different possible settings for each feature. Inherent channel variations and the possible interference conditions when operating in unlicensed spectrum necessitate adaptation of the various medium access control (MAC) and physical (PHY) layer features to ensure high performance. Selecting the values of those features to optimise a criterion such as throughput is the link adaptation problem. Link adaptation, the focus of this thesis, can play a key role in improving the performance of 802.11 WLANs. Increasing number of features and feature setting combinations with newer 802.11 standards is not only making link adaptation even more important but also more challenging. The contributions made in this thesis significantly advance the state of the art on link adaptation for 802.11 WLANs along three dimensions. First, we show that not knowing the exact cause of loss is not an impediment to effective link adaptation. Nevertheless, actions taken in response to losses are more crucial and they ought to be holistic and not solely dependent on the exact cause of loss. Second, we make significant methodological contributions for analysing the impact of multiple parameters on a given criterion, based on comprehensive experimental measurements. The application of this methodology on 802.11n measurements, examining the interaction of the protocols various parameters on performance under varying conditions, has lead to several valuable findings on how to perform efficient link adaptation in a complex WLAN scenario like 802.11n and future 802.11 standards. Adaptation should be holistic, based on the channel quality instead of the interference scenario, and independent of loss differentiation. Based on these insights, lastly and most importantly, we propose two novel holistic link adaptation schemes for legacy 802.11a/b/g and 802.11n WLANs, termed Themis and SampleLite, respectively. Both Themis and SampleLite take a hybrid approach relying on easily accessed channel quality information at the sender side to perform holistic adaptation. The hypothesis that adaptation should be holistic is validated by our results, with both Themis and SampleLite outperforming the current state of the art.

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Cheung, Sing Kwong. "Processor-sharing queues and resource sharing in wireless LANs." Enschede : University of Twente [Host], 2007. http://doc.utwente.nl/57875.

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Hasson, Albert M. "Mobile IP movement detection optimisations in 802.11 wireless LANs." Master's thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/6687.

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The IEEE 802.11 standard was developed to support the establishment of highly flexible wireless local area networks (wireless LANs). However, when an 802.11 mobile node moves from a wireless LAN on one IP network to a wireless LAN on a different network, an IP layer handoff occurs. During the handoff, the mobile node's IP settings must be updated in order to re-establish its IP connectivity at the new point of attachment. The Mobile IP protocol allows a mobile node to perform an IP handoff without breaking its active upper-layer sessions. Unfortunately, these handoffs introduce large latencies into a mobile node's traffic, during which packets are lost. As a result, the mobile node's upper-layer sessions and applications suffer significant disruptions due to this handoff latency. One of the main components of a Mobile IP handoff is the movement detection process, whereby a mobile node senses that it is attached to a new IP network. This procedure contributes significantly to the total Mobile IP handover latency and resulting disruption. This study investigates different mechanisms that aim to lower movement detection delays and thereby improve Mobile IP performance. These mechanisms are considered specifically within the context of 802.11 wireless LANs. In general, a mobile node detects attachment to a new network when a periodic IP level broadcast (advertisement) is received from that network. It will be shown that the elimination of this dependence on periodic advertisements, and the reliance instead on external information from the 802.11 link layer, results in both faster and more efficient movement detection. Furthermore, a hybrid system is proposed that incorporates several techniques to ensure that movement detection performs reliably within a variety of different network configurations. An evaluation framework is designed and implemented that supports the assessment of a wide range of movement detection mechanisms. This test bed allows Mobile IP handoffs to be analysed in detail, with specific focus on the movement detection process. The performance of several movement detection optimisations is compared using handoff latency and packet loss as metrics. The evaluation framework also supports real-time Voice over IP (VoIP) traffic. This is used to ascertain the effects that different movement detection techniques have on the output voice quality. These evaluations not only provide a quantitative performance analysis of these movement detection mechanisms, but also a qualitative assessment based on a VoIP application.

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Chinta, RaviTeja. "Jamming and anti-jamming in IEEE 802.11 wireless LANs." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024678.

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Shu, Feng. "Analysis and optimization of MAC protocols for wireless networks /." Connect to thesis, 2007. http://eprints.unimelb.edu.au/archive/00003857.

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Zhu, Fang. "Optimizations for vertical handoff in next generation wireless networks." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012983.

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Kao, Chi-han. "Performance of IEEE 802.11a wireless LAN standard over frequency-selective, slow, ricean fading channels /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02sep%5FKao.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, September 2002.
Thesis advisor(s): R. Clark Robertson, Roberto Cristi. Includes bibliographical references (p. 93-94). Also available online.

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Tope, Michael A. "Performance evaluation of a cooperative diversity enhanced ad hoc network." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FTope.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): John C. McEachen, R. Clark Robertson, Daniel M. Rosser. Includes bibliographical references (p. 73-75). Also available online.

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Hung, Lau Yung. "Link adaptation and scheduling in wireless local area network /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?COMP%202005%20HUNG.

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Kang, Jong Hee. "Location-aware information access through wireless networks /." Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/6878.

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Kypriotis, Georgios. "Prototype system for detecting and processing of IEEE 802.11G signals." Thesis, Monterey California. Naval Postgraduate School, 2004. http://hdl.handle.net/10945/1393.

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Approved for public release, distribution is unlimited
On the modern battlefield, successful and fast communications is a critical issue. So the need for transmitting information in larger amounts through a military high-speed network increases. Thus the military is seeking viable and effective solutions that may fulfill these requirements in an operational environment. This thesis develops a prototype system based on appropriate low-cost software and hardware solutions. This system is able to detect, analyze and process wireless 802.11g signals. The evaluation of the newly designed system proved that it is effective up to distances of about 400 m with a low packet error rate and could be a useful tool for detecting wireless 802.11g networks. After evaluating the system, it was used for capturing wireless signals so that we would determine the effective transmission range and the data throughput of an 802.11g network. We determined that such a wireless network could be used in military operations because it offers high data rates up to 200 m, while it maintains a connection of the wireless clients for distances up to 400 m. In addition, the performance data collected can be used as guidelines for estimating the expected performance in an operational situation and can provide useful information for successful planning.
Lieutenant, Hellenic Navy

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Lock, Jeffrey S. "Deployable combat simulations via wireless architectures /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FLock.pdf.

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Thesis (M.S. in Computer Science)--Naval Postgraduate School, March 2004.
Thesis advisor(s): Dr. Rudolph Darken, CDR Joseph Sullivan. Includes bibliographical references (p. 79-80). Also available online.

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Boom, Derrick D. "Denial of service vulnerabilities in IEEE 802.16 wireless networks." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FBoom.pdf.

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Perchalski, Steven Joseph. "Shipboard sensor closed-loop calibration using wireless LANs and DataSocket transport protocols." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Jun%5FPerchalski.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2003.
Thesis advisor(s): Xiaoping Yun, Fotis Papoulias. Includes bibliographical references (p. 81-82). Also available online.

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Chan, Hsiung Wei Roy. "Performance analysis of IEEE 802.11A signals under different operational environments." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sept%5FChan.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, Sept. 2004.
Thesis advisor(s): Tri T. Ha, Randy L. Borchardt. Includes bibliographical references (p. 89). Also available online.

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Lal, Sanjay. "Distributed resource allocation for DS-CDMA-based multimedia wireless LANs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq29411.pdf.

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Forsgren, Daniel. "Robust scalable video multicast and performance issues in wireless LANs /." Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-509.

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Ratnayake, Deepthi N. "Probe request attack detection in wireless LANs using intelligent techniques." Thesis, London Metropolitan University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590106.

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This work demonstrates a new intelligent approach to recognise probe request attacks in Wireless Local Area Networks (WLAN). In WLANs, management frames facilitate wireless stations (STA) to establish and maintain communications. In infrastructure WLANs, any mobile STA can send a probe request management frame when it needs information from an Access Point CAP). AP replies to any probe request from a STA with a known Medium Access Control (MAC) address, with a probe response management frame with capability information, and supported data rates. The next step is to establish its identity with the AP through authentication messages. Once authentication is completed, STAs can associate (register) with the AP to gain full access to the network. Probe request and response management frames are unprotected, so the information is visible to sniffers. MAC addresses can be easily spoofed to bypass AP access lists. Probe requests can be sent by anyone with a legitimate MAC address, as association to the network is not required at this stage. Attackers take advantage of these vulnerabilities and send a flood of probe request frames that can lead to a Denial-of-Service (DoS) to legitimate STAs. The research investigates and analyses delta-time, sequence number, Signal Strength Indicator (SSI), and frame sub-type of traffic captured on a home WLAN, and uses a feed forward supervised Neural Network (NN) sensor/classifier, with four input neurons, a single hidden layer, and an output neuron, to determine the results. The research also utilises self-consistency test to measure the fitness of the data in the sensor/classifier, and 5-fold cross-validation method to evaluate the sensor/classifier with unseen data. Five Genetic Algorithms (GA) are utilised to optimise the NN using training, validation, and testing sample percentages and number of neurons of the hidden layer. The most optimised NN classifier, with training, validation and test, and sample sizes 40%, 59%, 1 %, and hidden neurons 29, produced 100% accuracy on a test sample.

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Mola, Guilo. "Interactions of Vertical Handoffs with 802.11b wireless LANs : Handoff Policy." Thesis, KTH, Mikroelektronik och Informationsteknik, IMIT, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-93067.

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Nomadic computing aims to be a leading short term revolution in the Internet, however to succeed in this the infrastructure, the protocols, the handoff mechanisms have to be designed and implemented to provide mobile computing with both reliability and transparency. A good deal of the work is addressed by mobile IP itself, but addressing wireless diversity is perhaps the most important next step. Many different wireless technologies are available; while one technology might provide wide coverage, another provides higher bandwidth, but can only be deployed locally, even uni-directional ad-hoc links can be used to carry IP traffic. To take full advantage of the potential infrastructure, a mobile device, with multiple network interfaces, should be able to dynamically switch from one link technology to another; hopefully totally transparently to the user. Moreover, having multiple interfaces allows the device to choose, each time a new connection is established, which interface to select to route the datagrams through, based on the type of service desired. In this thesis a possible solution is presented, involving both vertical handoff optimization and policy management. Our testing device is the the SmartBadge v4, provided with a GPRS link and a 802.11b WLAN interface.
Nomadic Computing har för avsikt att revolutionera dagens Internet tillämpningar. För att lyckas måste dock infrastrukturen, IT protokollen och handoff procedurer utformas och implementeras med intentionen att förse mobilt dataöverföring med både driftsäkerhet och autonoma processer. En stor del av de nödvändiga förutsättningarna är tillgängliga tack vare Mobile IP, men mångfalden inom de befintliga Wireless teknologierna utgör fortfarande ett problem. Det stora antalet disponibla Wireless tekniker varierar från teknologierer som förser användaren med en stor täckningsgrad, till sådana som förser användaren med högre bandbredd, begränsad till lokala anv ändningområden. Även Uni-directional ad-hoc links kan läggas i denna lista av mångfald. För att förverkliga fördelarna med den tänkta infrastrukturen fullt ut måste den mobila enheten kunna utföra omkopplingar från den ena wireless teknologin till den andra, med syftet att vara osynlig för användaren. Utöver detta är det meningen att en apparat med många anslutningar ska kunna välja den anslutning som passar bäst, var gång en ny koppling ska göras, beroende på den tjänst som efterfrågas. Det här examensarbetet presenterar en möjlig lösning, som utnyttjar både Vertical Handoff optimering och Policy Management. Prototyp-enheten vi anv änder oss av för att genomföra undersökningen är Smart Badge v4, utrustad med GPRS och 802.11b Wireless LAN anslutningar.

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41

Hung, Ka-Lok. "The fair data collection problem in wireless sensor networks /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?COMP%202006%20HUNG.

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Jaiaree, Thoetsak. "The security aspects of wireless local area network (WLAN)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03sep%5FJaiaree.pdf.

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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, September 2003.
Thesis advisor(s): Norman F. Schneidewind, Douglas E. Brinkley. Includes bibliographical references (p. 75-78). Also available online.

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Mundi, Anuj V. "PLC-WiFi hybrid broadband Internet deployment and security /." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0006964.

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Xia, Qiuyan. "Rate adaptation and resource allocation for wireless networks /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20XIA.

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Tsoumanis, Andreas. "Performance analysis of the effect of pulsed-noise interference on WLAN signals transmitted over a Nakagami fading channel." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FTsoumanis.pdf.

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Thesis (M.S. in Electrical Engineering and M.S. in Systems Engineering)--Naval Postgraduate School, March 2004.
Thesis advisor(s): R. Clark Robertson. Includes bibliographical references (p. 67-68). Also available online.

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46

Javali, Nagesh. "Topology control for wireless ad-hoc networks." Click here for download, 2008. http://proquest.umi.com/pqdweb?did=1580780361&sid=1&Fmt=2&clientId=3260&RQT=309&VName=PQD.

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Thesis (M.S.)--Villanova University, 2008.
"This research work is funded in part by National Science Foundation (NSF), Computing and Communication Foundation (CCF) award 0728909"--P. iii. Computer Science Dept. Includes bibliographical references.

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Tan, Godfrey, and John Guttag. "Capacity Allocation in Wireless LANs." 2004. http://hdl.handle.net/1721.1/30503.

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Today's access point based wireless LANs (WLANs) are inefficient and unfair. For many traffic loads they provide far less total throughput than they should, and do a poor job allocating what throughput they do deliver. Inappropriate association of nodes to access points and rates to flows plays a large role in these problems. We address a major root cause of this problem in this paper.Current practice ignores the distinction between flows that connect two wireless nodes via an access point and flows that connect wireless nodes to the wired infrastructure. As wireless devices and applications become more pervasive, ignoring this distinction will lead to a significant degradation in perceived performance.In this paper, we i) describe a series of examples that illustrates the impact of two-hop flows on the performance of the system, ii) provide a practical algorithm to solve the AP-assignment problem and iii) evaluate the performance of our algorithm against other approaches. Our preliminary results show that our algorithm can increase average achieved throughput by as much as 50% for some traffic loads.

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謝文川. "The Proactive Wireless Intrusion Prevention Mechanism for Wireless LANs." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/35619086787407973802.

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Hsu, Chiang-Shan, and 許江山. "Quality of Service over Wireless LANs." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/26892461795301906884.

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碩士
國立臺灣大學
電機工程學研究所
91
IEEE 802.11 provides high bandwidth connectivity in a local area network (LAN) environment that is suitable for most data applications but it does not meet the quality of service (QoS) requirements for real-time data traffic applications such as voice, audio and video transmissions. There have been recent proposals on enhancements to the IEEE 802.11 Medium access control (MAC) protocol to provide expedited access to the shared wireless network for real-time data transmissions. We propose the combined use of traffic flow control and burst control and expedited transmission of higher priority data over the shared wireless network as the mechanisms to provide QoS guarantee for real-time application data traffic in IEEE 802.11 Wireless LANs.

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Fan, Gang-Ming, and 范綱明. "Location-Based Push Services in Wireless LANs." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/97862667757108669701.

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碩士
國立暨南國際大學
資訊管理學系
93
IEEE 802.11 wireless local area networks (WLANs) can be built in one of two modes: ad-hoc mode and infrastructure mode. In the infrastructure mode, an access point (AP) is required to act as a bridge by which mobile nodes can communicate with each other or connect to wired networks. The cell size of a WLAN is usually small. Besides, a mobile node will make an association with an AP nearest to the node. Therefore, it is practical to develop location-based services based upon the awareness of the WLAN AP that mobile nodes currently access. In this thesis, we will discuss how to develop location-based push services in WLANs. It will be shown that the location of a mobile client can be determined effectively through an SNMP Trap approach. When a mobile node makes an association with an AP, the AP will send an SNMP trap to its management station. The MAC address of the mobile node will be presented in the trap. Therefore, the current location of the mobile node can be determined by knowing the location of the AP. To further deliver location-based information to the mobile node, we also have to know the current IP address of the mobile node. Therefore, the SNMP Trap approach will also involve an effective address mapping scheme to find the IP address of a mobile node from its MAC address. In this thesis, we will also develop a location-based push service framework to enable the delivery of location dependent push messages to all mobile nodes within a specific area. In addition, the framework also allows the delivery of instant location dependent push messages to a mobile node immediately after the mobile node roams into a specific area. The proposed location-based push service framework is a generic one for most location-based push services. Based on the framework, we will also develop a personalized advertising application to verify the soundness of the framework.

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Dissertations / Theses on the topic 'Wireless LANs'

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