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Tesi sul tema "Wireless Internet"
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Hoene, Christian. "Internet telephony over wireless links". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=979194121.
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Chatziioannidis, Ioannis. "High speed internet access using cellular infrastructure". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sept%5FChatziioannidis.pdf.
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Nguyen, Dang Thanh. "Fountain codes for the wireless Internet". Thesis, University of Southampton, 2008. https://eprints.soton.ac.uk/64484/.
Testo completoAbstract (sommario):
In this thesis, novel Foutain codes are proposed for transmission over wireless channels. The thesis concentrates on a specific version of Fountain codes, namely on Luby transform codes. More specifically, we consider their concatenation with classic error correction codes, yielding schemes, such as the concatenated Luby Transform and Bit Interleaved Coded Modulation using Iterative Decoding (LT-BICM-ID), the amalgamated Luby Transform and Generalized Low Density Parity Check (LT-GLDPC) code, or the Luby Transform coded Spatial Division Multiple Access (LT-SDMA) scenario considered. The thesis also investigates the potential of Systematic Luby Transform (SLT) codes using soft-bit decoding and analyses their Bit Error Ratio (BER) performance using EXtrinsic Information Transfer (EXIT) charts. SLT codes using different degree distributions and random integer packet index generation algorithms for creating the parity and information part of the SLT codeword are also investigated in this thesis. For the sake of improving both the BER performance and the diversity gain of Vertical Bell Laboratories Layered Space Time (V-BLAST) schemes, in this thesis a SLT coded V-BLAST system having four transmit and four receive antennas is proposed. Finally, A Hybrid Automatic Repeat reQuest (H-ARQ) SLT coded modulation scheme is designed in this thesis, where SLT codes are used both for correcting erroneous bits and for detecting as well as retransmitting erroneous Internet Protocol (IP) based packets. Erroneous IP packet detection is implemented using syndrome checking with the aid of the SLT codes’ Parity Check Matrix (PCM). Optimizing the mapping of SLT-encoded bits to modulated symbols and then using iterative decoding for exchanging extrinsic information between the SLT decoder and the demapper substantially improves the achievable Bit Error Ratio (BER) performance of the scheme.
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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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Syed, Hamid Mahmood. "Performance of Internet applications over wireless CDMA". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0021/MQ48461.pdf.
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Nikituk, Marko J. E. "SEANET remote wireless internet Project Management Plan". Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/8945.
Testo completoAbstract (sommario):
Approved for public release; distribution is unlimitedUbiquitous computing, the ability to use computer resources anywhere and at anytime to accomplish tasks, is a capability that is in much demand. The Internet has provided an opportunity to meet this demand. However, access to the Internet is limited by connections to land based wired systems. In order to truly achieve effective ubiquitous computing, technology must be developed that extends internet access to remote and mobile platforms by using wireless access. The SEANET is a proof of concept collaborative project seeking to extend Internet access to the sea for the Oceanographic Research Fleet. This thesis studies how the Internet evolved to draw lessons learned that can be applied to the development of SEANET. It also presents a possible method for more effectively meeting the SEANET goals through use of a Project Management Plan
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Syed, Hamid Mahmood Carleton University Dissertation Engineering Systems and Computer. "Performance of Internet applications over wireless CDMA". Ottawa, 1999.
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Rivera-Cintron, Carlos A. "Wireless instant voice messaging using the Internet". [Florida] : State University System of Florida, 2000. http://etd.fcla.edu/etd/uf/2000/amt2429/thesisBook%5F4%5F26.pdf.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Florida, 2000.Title from first page of PDF file. Document formatted into pages; contains viii, 262 p.; also contains graphics. Vita. Includes bibliographical references (p. 259-261).
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Akan, Ozgur Baris. "Advanced Transport Protocols for Next Generation Heterogeneous Wireless Network Architectures". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5231.
Testo completoAbstract (sommario):
The revolutionary advances in the wireless communication technologies are inspiring the researchers to envision the next generation wireless networking architectures, i.e., Next Generation Wireless Internet (NGWI), InterPlaNetary (IPN) Internet, and Wireless Sensor Networks (WSN). There exist significant technological challenges for the realization of these envisioned next generation network architectures. NGWI will be the convergence of the Internet and heterogeneous wireless architectures, which have diverse characteristics and hence pose different sets of research challenges, to achieve anywhere, anytime seamless service to the mobile users. Similarly, the unique characteristics and challenges posed by deep space communications call for novel networking protocols to realize the IPN Internet objective. Furthermore, in order to realize the potential gains of WSN, it is imperative that communication challenges imposed by resource constraints of sensor nodes must be efficiently addressed with novel solutions tailored to the WSN paradigm. The objective of this research is to develop new advanced transport protocols for reliable data transport and real-time multimedia delivery in the next generation heterogeneous wireless network architectures. More specifically, the analytical rate control (ARC) protocol for real-time multimedia delivery is first proposed for wired/wireless hybrid networks. Next, a new rate control scheme (RCS) is proposed to achieve high throughput performance and fairness for real-time multimedia traffic over the satellite links. The unified adaptive transport layer (ATL) suite and its protocols for both reliable data transport (TCP-ATL) and real-time multimedia delivery (RCP-ATL) are introduced for the NGWI. A new reliable transport protocol for data transport in the IPN Internet (TP-Planet) is then proposed to address the unique challenges of the IPN Internet backbone links. A new integrated tranmission protocol (ITP) is then proposed for reliable data transport over multihop IPN Internet paths. Finally, the event-to-sink reliable transport (ESRT) protocol is proposed to achieve reliable event transport with minimum energy expenditure in WSN.
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Baccelli, Emmanuel. "IP-Disruptive Wireless Networking: Integration in the Internet". Habilitation à diriger des recherches, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00770791.
Testo completoAbstract (sommario):
The super collision between the Internet phenomenon and the wireless communication revolution gives birth to a wealth of novel research problems, design challenges and standardization activities. Within this domain, spontaneous wireless IP networking are probably the most extreme example of new ''particles'' born from the collision. Indeed, these particles defy the laws of the Internet in many ways. The absorption of such peculiar particles in the global IP network has already started thanks to pioneering algorithmic and protocol work -- for instance OLSR -- and through the deployment of wireless mesh networks around the world, such as urban community wireless networks. With the recent revolutions in North Africa, and movements such as Occupy Wall Street, the prospect of spontaneous wireless IP networking has become even more attractive on social and political grounds. Dedicated conferences have recently been organized, and as a result, ambitious, multi-million dollar initiatives have been launched (e.g. the US Government-funded project Commotion Wireless, or the EU-funded initiative CONFINE). However, spontaneous IP wireless networks are not yet widely deployed because pioneer work such as OLSR is vastly insufficient to fully bridge the gap between the Internet and these new networks. This thesis presents work that analyzes this gap and proposes some solutions as to how to bridge it. The focus is put on three domains: a first part presents work in the domain of wireless mesh and ad hoc networks. A second part presents work on sensor networks and in the Internet of Things. And the last part presents work in the domain of delay tolerant networking and vehicular networks.
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Nazim, Umair. "Securing Internet of Things (IoT)". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20275.
Testo completoAbstract (sommario):
The Internet of Things (IoT) is our future and human life is now entering in to a generation where everyone will be using sensory information and artificial intelligence to make day to day life decisions in real-time. With implementation and enhancements around Internet protocol (IP) now it’s possible to connect and control these devices from anywhere around the globe they can be control by either human or even machines. Security is a critical element and building block for Internet of things (IoT) success. First, we have worked finding out possibility of detecting different types of attacks in Internet of things Wireless networks and identify them based on throughput, delay and energy consumed. Attack that we have work on include DOS attacks and DDOS attacks. Motivated by current use of Blockchain in resolving various problems we have evaluated its implementation to find solutions to secure Internet of Things. This become possible by utilising block chain network and smart contracts to validate any IoT communication . Using Blockchain network allowed IoT to detect securely authenticate without over utilizing device resource keeping in mind the limited hardware and bandwidth. IoT node or nodes communicates to a validator node within Blockchain network to get the most current binary of contracts status and in order to achieve this all the devices required to be in sync with Blockchain version of accounts stored by this validator node. We have worked out how this communication will work in order to ensure security and privacy while doing performance analysis of overheads. In conclusion IoT and Blockchain combine together is very promising solution to solve many current security issues in order to take it to mass scale deployment which allow implementation of Internet of things for a purposeful manner.
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Workman, Stephen J. H. "AMPM Adaptive multipoint multimedia over wireless internet protocol networks". Thesis, University of Ulster, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529585.
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Xue, Lei. "Internet connection method for mobile ad hoc wireless networks". Thesis, University of Warwick, 2005. http://wrap.warwick.ac.uk/3644/.
Testo completoAbstract (sommario):
In recent years, wireless networks with Internet services have become more and more popular. Technologies which integrate Internet and wireless networks have extended traditional Internet applications into a more flexible and dynamic environment. This research work investigates the technology that supports the connection between a Mobile Ad Hoc Wireless Network (MANET) and the Internet, which enables the current wireless Internet technologies to provide a ubiquitous wireless life style. With detailed analysis of the existing wireless Internet technologies and MANETs regarding their features and applications, the demand and lack of research work for an application to provide Internet connection to MANET is indicated. The primary difficulty for MANET and Internet connection is that the dynamic features of MANET do not suit the traditional connection methods used in infrastructure wireless networks. This thesis introduces new concept of the 'Gateway Awareness' (GAW) to the wireless devices in the MANET. GAW is a new routing protocol designed by the author of this thesis, at the University of Warwick. Based on GAW, an inclusive definition for the connection method, which supports the Internet connection and keeps the independency of routing in MANET, is addressed. Unlike other research work, this method supports the MANET and Internet communication in both directions. Furthermore, it explores possible ways of using the Internet as an extension for wireless communications. The GAW routing method is developed from destination sequenced distance vector (DSDV) routing protocol. However, it defines a layer of wireless nodes (known as GAWNs) with exclusive functions for the Internet connection task. The layer of GAWNs brings a new set of route update and route selection method. Simulations show that the GAW routing method provides quality Internet connection performance in different scenarios compared with other methods. In particular, the connection is completed with minimum effect on the independent MANET while the routing efficiency and accuracy is guaranteed.
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Thomas, Darshana. "Optimal wireless technologies for the Internet of Things (IoT)". Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=28633.
Testo completoAbstract (sommario):
The Internet of Things (IoT) - connection of small smart sensors, actuators and other devices to the Internet - is a key concept within the smart home. To ease deployment, such devices are often wireless and battery powered. An important question is the wireless interface used. As these small sensors are increasing in number, the need to implement these with much more capable and ubiquitous transmission technology is necessary. The ubiquity of Wi-Fi in homes today makes this an attractive option, but the relatively high power requirements of Wi-Fi conflict with the requirement for long battery life and low maintenance. Lower power alternatives, such as Bluetooth and Zigbee, have been proposed, but these have a much smaller installed base. In addition, many Smart Home products are currently available using 433MHz technology. This thesis considers whether it is possible to reduce Wi-Fi power usage to the point where cheap Wi-Fi based products can be used instead of other protocols. A low cost Wi-Fi inbuilt IoT prototype was developed and tested for the purpose of the experiment carried out for this thesis, part of Treegreen project. The work in this thesis undertakes power analysis of a wireless sensor with a System on Chip (SoC) Wi-Fi module, with and without a separate microcontroller, optimized for low power usage which can be used to control the Wi-Fi module. The Wi-Fi chip used within the prototype is the ESP8266- ESP03. Based on the results, in order to optimize the power consumption of the Wi-Fi chip, an MSP430 microcontroller was added onto the existing device. Finally, the IoT data in LTE network is investigated and compared with the real world IoT data.
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Park, Taehyeun. "Distributed Wireless Resource Management in the Internet of Things". Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/99055.
Testo completoAbstract (sommario):
The Internet of Things (IoT) is a promising networking technology that will interconnect a plethora of heterogeneous wireless devices. To support the connectivity across a massive-scale IoT, the scarce wireless communication resources must be appropriately allocated among the IoT devices, while considering the technical challenges that arise from the unique properties of the IoT, such as device heterogeneity, strict communication requirements, and limited device capabilities in terms of computation and memory. The primary goal of this dissertation is to develop novel resource management frameworks using which resource-constrained IoT devices can operate autonomously in a dynamic environment. First, a comprehensive overview on the use of various learning techniques for wireless resource management in an IoT is provided, and potential applications for each learning framework are proposed. Moreover, to capture the heterogeneity among IoT devices, a framework based on cognitive hierarchy theory is discussed, and its implementation with learning techniques of different complexities for IoT devices with varying capabilities is analyzed. Next, the problem of dynamic, distributed resource allocation in an IoT is studied when there are heterogeneous messages. Particularly, a novel finite memory multi-state sequential learning is proposed to enable diverse IoT devices to reallocate the limited communication resources in a self-organizing manner to satisfy the delay requirement of critical messages, while minimally affecting the delay-tolerant messages. The proposed learning framework is shown to be effective for the IoT devices with limited memory and observation capabilities to learn the number of critical messages. The results show that the performance of learning framework depends on memory size and observation capability of IoT devices and that the learning framework can realize low delay transmission in a massive IoT. Subsequently, the problem of one-to-one association between resource blocks and IoT devices is studied, when the IoT devices have partial information. The one-to-one association is formulated as Kolkata Paise Restaurant (KPR) game in which an IoT device tries to choose a resource block with highest gain, while avoiding duplicate selection. Moreover, a Nash equilibrium (NE) of IoT KPR game is shown to coincide with socially optimal solution. A proposed learning framework for IoT KPR game is shown to significantly increase the number of resource blocks used to successful transmit compared to a baseline. The KPR game is then extended to consider age of information (AoI), which is a metric to quantify the freshness of information in the perspective of destination. Moreover, to capture heterogeneity in an IoT, non-linear AoI is introduced. To minimize AoI, centralized and distributed approaches for the resource allocation are proposed to enable the sharing of limited communication resources, while delivering messages to the destination in a timely manner. Moreover, the proposed distributed resource allocation scheme is shown to converge to an NE and to significantly lower the average AoI compared to a baseline. Finally, the problem of dynamically partitioning the transmit power levels in non-orthogonal multiple access is studied when there are heterogeneous messages. In particular, an optimization problem is formulated to determine the number of power levels for different message types, and an estimation framework is proposed to enable the network base station to adjust power level partitioning to satisfy the performance requirements. The proposed framework is shown to effectively increase the transmission success probability compared to a baseline. Furthermore, an optimization problem is formulated to increase sum-rate and reliability by adjusting target received powers. Under different fading channels, the optimal target received powers are analyzed, and a tradeoff between reliability and sum-rate is shown. In conclusion, the theoretical and performance analysis of the frameworks proposed in this dissertation will prove essential for implementing an appropriate distributed resource allocation mechanisms for dynamic, heterogeneous IoT environments.Doctor of Philosophy
The Internet of Things (IoT), which is a network of smart devices such as smart phones, wearable devices, smart appliances, and environment sensors, will transform many aspects of our society with numerous innovative IoT applications. Those IoT applications include interactive education, remote healthcare, smart grids, home automation, intelligent transportation, industrial monitoring, and smart agriculture. With the increasing complexity and scale of an IoT, it becomes more difficult to quickly manage the IoT devices through a cloud, and a centralized management approach may not be viable for certain IoT scenarios. Therefore, distributed solutions are needed for enabling IoT devices to fulfill their services and maintain seamless connectivity. Here, IoT device management refers to the fact that the system needs to decide which devices access the network and using which resources (e.g., frequencies). For distributed management of an IoT, the unique challenge is to allocate scarce communication resources to many IoT devices appropriately. With distributed resource management, diverse IoT devices can share the limited communication resources in a self-organizing manner. Distributed resource management overcomes the limitations of centralized resource management by satisfying strict service requirements in a massive, complex IoT. Despite the advantages and the opportunities of distributed resource management, it is necessary to address the challenges related to an IoT, such as analyzing intricate interaction of heterogeneous devices, designing viable frameworks for constrained devices, and quickly adapting to a dynamic IoT. Furthermore, distributed resource management must enable IoT devices to communicate with high reliability and low delay. In this regard, this dissertation investigates these critical IoT challenges and introduces novel distributed resource management frameworks for an IoT. In particular, the proposed frameworks are tailored to realistic IoT scenarios and consider different performance metrics. To this end, mathematical frameworks and effective algorithms are developed by significantly extending tools from wireless communication, game theory, and machine learning. The results show that the proposed distributed wireless resource management frameworks can optimize key performance metrics and meet strict communication requirements while coping with device heterogeneity, massive scale, dynamic environment, and scarce wireless resources in an IoT.
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Haas, Michael. "Management of innovation in network industries : mobile internet in Japan and Europe /". Wiesbaden : Dt. Univ.-Verl, 2006. http://www.gbv.de/dms/zbw/509011543.pdf.
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Chevul, Stefan. "On Application-Perceived Quality of Service in Wireless Networks". Licentiate thesis, Karlskrona : Department of Telecommunication Systems, School of Engineering, Blekinge Institute of Technology, 2006. http://www.bth.se/fou/Forskinfo.nsf/allfirst2/542371ed20d9e149c1257242005c071a?OpenDocument.
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Taaghol, Pouya. "Multiple access protocols for mixed services wireless packet communications". Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/844476/.
Testo completoAbstract (sommario):
Packet communications have increasingly become popular since the launch of the first ever packet-switched network, the ARPANET. Evolution of such networks resulted in creation of the Internet, the global packet-switched network. Amongst the well-known advantages of packet-switching are service transparency, cost-effectiveness, and high system capacity. A natural pathway will incorporate tetherless mobility features to packet services. The key component to realisation of wireless packet communication is the multiple access technology (the subject of this thesis), capable of optimum sharing of scarce radio resources amongst a diverse set of packetized information sources. Based on core features of packet multiple access protocols, a classification is presented by which most proposed protocols could be mapped into. For mixed services, two equivalent offered loads, namely ''access load" and "traffic load", are derived. The former can be used for design, optimisation, and stabilisation of the access mechanism, whilst the latter is to evaluate the overall system performance. The proposed normalised offered loads are found accurate and instrumental in predicting and designing packet access protocols for mixed services. "Statistical upper-bounds" for packet access protocols are derived (both for random access and general access mechanisms), based on which an "efficiency factor" is defined to evaluate and compare merits of protocols against each other. Conventionally, analysis of resource-sharing systems with mixed services (such as multiple access protocols) involve multidimensional Markov chains which become quite intractable for more than two service types. In order to avoid multidimensional Markov analysis, an analytical method called "Aggregate Source Modelling" is proposed by means of which various service types are aggregated into a representative service type. The proposed method is deployed to analyse various queueing and multiple access scenarios. Finally, a series of multiple access protocols are presented for adapting real-time and non-real-time packet services to existing cellular and satellite systems. For evaluation purposes, the proposed statistical models of packet services (such as FTP, E- mail, WWW, packet voice, and so forth) are used throughout the thesis. These models have components of various statistical distributions, namely, Poisson (Exponential), lognormal, Pareto, Cauchy, Gaussian, Geometric, and Hyper-Exponential. Extensive discrete-time simulation models have been developed for evaluation purposes.
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Hansson, Niclas, Alexander Lantz e Ludvig Fischerström. "A Security Analysis of Wireless Smart Home Technologies". Thesis, Linköpings universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113256.
Testo completoAbstract (sommario):
The use of electronics connected to local networks and the Internet is growingall the time. Nowadays you can control your electronics in your house even when away from home, which opens up for potential security threats. The purpose of this report is to point out the potential risks with connecting home electronics to the Internet and to shed light on what security mechanisms that are needed in these kinds of systems. This report contains a theoretical part in which relevant material has been summarized. This material includes the smart home solution Tellstick Net and the wireless technologies ZigBee and Z-Wave, which are commonly used in home automation. The Tellstick Net system was mapped out and a risk analysis with attack trees was performed. After the analysis of the system, the implementation of two potential security threats were attempted. The two attempted attacks were replay attack and cross-site request forgery. The replay attack was unsuccessful due to the way the system communicates and keeps connections alive. However, the cross-site request forgery was discovered to be successful in some cases. It depended on if the browser of the target supported cross-origin resource sharing, as that property protects against cross-site request forgery. Finally, the report discusses what impact the found security deficiencies have, what they entail and how they reflect on the need for security in smart technologies for the home.
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Allen, Jared L. "Performance analysis of 802.61a". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FAllen.pdf.
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Silva, José Miguel Costa. "Content distribution in OTT wireless networks". Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22733.
Testo completoAbstract (sommario):
Mestrado em Engenharia Electrónica e de TelecomunicaçõesIn developed countries, the Internet is increasingly considered an essential and integral part of people's lives. The need to be \online", share and access content are frequent routines in people's daily lives, making the Internet one of the most complex systems in operation. Most traditional communications (telephone, radio and television) are being remodelled or rede ned by the Internet, giving rise to new services such as Voice over Internet Protocol (VoIP) and Internet Protocol Television (IPTV). Books, newspapers and other types of printed publications are also adapting to the web technology or have been redesigned for blogs and feeds. Massi cation of the Internet and the constant increase in bandwidth o ered to the consumers have created excellent conditions for services such as OTT. OTT Services refer to the delivery of audio, video and other data over the Internet without the control of network operators. Although the OTT delivery presents an attractive solution (and pro table, looking at the fast growing services such as YouTube, Skype and Net ix, for example), it su ers from some limitations. It is necessary to maintain high levels of Quality-of-Experience (QoE) to continue to attract customers. In order to do this, a content distribution network is fundamental to adapt to the speed with which the contents are required and quickly discarded and that can accommodate all the tra c. This dissertation focuses on the distribution of OTT contents in wireless networks, in order to address the lack of research work in this area. A solution is proposed that can be integrated by the network equipment so that it is able to predict what kind of content consumers connected (or nearby) may request and put it in memory before being requested, improving consumers' perception of the service. Given the lack of information in the literature on management and control of proxy caches for embedded systems, the rst step was to test and evaluate two di erent cache algorithms: Nginx and Squid. The results show that there is a trade-o between cache performance and speed in processing the requests, with Nginx delivering better performance but worse response times. It was also found that cache size does not always determine a signi cant improvement in results. Sometimes keeping just the most popular content cached is enough. Afterwards, two algorithms for predicting prefetching contents in mobility scenarios were proposed and tested, given the characteristics of the wireless networks, where it was possible to observe very signi cant performance improvements, demonstrating that there is a possibility for an investment in this area, although this implies an increase in the processing capacity and power consumption of the network equipment.
Nos países desenvolvidos, cada vez mais a Internet é considerada um bem essencial. A necessidade de estar \online", partilhar e aceder a conteúdos são rotinas frequentes no dia-a-dia das pessoas, tornando assim a Internet num dos sistemas mais complexos em operação. A maioria das comunicações tradicionais (telefone, radio e televisão) estão a ser remodeladas ou redefinidas pela Internet, dando origem a novos serviços, como o protocolo de Internet por voz (VoIP) e o protocolo de Internet de televisão (IPTV). Livros, jornais e outro tipo de publicações impressas estão também a adaptar-se á tecnologia web ou têm sido reformuladas para blogs e feeds. A massificação da Internet e o aumento constante das larguras de banda oferecidas aos consumidores criaram condiçoes excelentes para serviços multimedia do tipo Over-The-Top (OTT). Serviços OTT referem se á entrega de áudio, vídeo e outros via Internet sem usar o controlo dos operadores de rede. Apesar da entrega OTT apresentar uma proposta atractiva (e lucrativa, olhando para o rápido crescimento de servicos como o YouTube, Skype e Net ix, por exemplo) esta sofre de algumas limitações. É necessario manter n veis elevados de Qualidade-de-Experi^encia (QoE) para continuar a atrair clientes. Para isso é fundamental uma rede de distribuição de conteúdos capaz de se adaptar á rapidez com que os conteúdos são requeridos e rapidamente descartados e que consiga albergar todo o tráfego. Esta dissertação foca-se na distribuição de conteúdos OTT nas redes sem fios, por forma a endereçar a falta de trabalhos de investigação nesta área. É proposta uma solução que visa poder ser integrada pelos equipamentos de rede para, desta forma, estes serem capazes de prever que tipo de conteúdo os consumidores conectados (ou nas proximidades) possam vir a solicitar e coloca-lo em memoria antes de ser pedido, melhorando a percepção com que os consumidores recebem o mesmo. Dada a falta de informação na literatura sobre gestão e controlo de proxy caches para sistemas embutidos, o primeiro passo foi testar e avaliar dois algoritmos de cache diferentes: Nginx e Squid. Os resultados mostram que existe um compromisso entre o desempenho de cache e velocidade no processamento dos pedidos, apresentando o Nginx um melhor desempenho mas piores tempos nas respostas aos pedidos. Foi também verificado que o tamanho da cache nem sempre determina um melhoramento significativo nos resultados. Ás vezes, manter apenas o conteúdo mais popular em cache é suficiente. De seguida, foram propostos e testados dois algoritmos de previsão de conteúdos (prefetching ) em cenários de mobilidade, dada as características das redes sem fios, onde foi possível observar melhorias de desempenho muito significativas, demonstrando que existe a possibilidade de ser viável um investimento nesta área, embora isto implique um aumento na capacidade de processamento/ consumo de energia dos equipamentos de rede.
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AlMaharmeh, Bassam T. "QoS-enabled integration of wireless sensor networks and the internet". Thesis, Monterey, Calif. : Naval Postgraduate School, 2005. http://bosun.nps.edu/uhtbin/hyperion-image.exe/05Sep%5FAlMaharmeh.pdf.
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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, September 2005.Thesis Advisor(s): Su, Weilian. "September 2005." Description based on title screen as viewed on November 7, 2007. Includes bibliographical references (p. 91-93). Also available in print.
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Cushnie, John. "QoS charging for Internet access networks : the wireless QoS gateway". Thesis, Lancaster University, 2003. http://eprints.lancs.ac.uk/12300/.
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Sun, Ziran. "Service differentiation : enhancing Internet application performance over optical wireless links". Thesis, University of Warwick, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404856.
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de, Villiers Gary. "Development of an internet gateway for a wireless sensor network". Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/2204.
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Thesis (MTech(Electrical Engineering))--Cape Peninsula University of Technology, 2012.Wireless Sensor Networks (WSNs) are being employed frequently to gather data from an ever-increasing variety of environments and phenomena. \iVSNs offers users in the industrial and academic community a low power, unobtrusive, adaptable and wireless alternative to traditional sensing equipment. This study focuses on the development of a configurable, low power and cost-effective gateway that will link a WSN to the Internet. In addition, the gateway provides onsite storage for the data collected by the WSN which may be uploaded at a scheduled time to a computer at a specified Internet address through a GSM or Ethernet link. Furthermore, the gateway provides a suitable platform capable of executing a variety of multitasking operating systems such as Windows Embedded CE or Linux. This multi-platform support permits the gateway the flexibility, through custom user applications, to adapt its functionality to the requirements of a WSN elm I the environments into which these networks may be deployed. This study has been successful in the design and development of a low-cost gateway solution, allel has produced a functional prototype system,
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Celosia, Guillaume. "Privacy challenges in wireless communications of the Internet of Things". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI069.
Testo completoAbstract (sommario):
Également connue sous le nom d'Internet des Objets (IdO), la prolifération des objets connectés offre des opportunités sans précédent aux consommateurs. Des moniteurs d'activité physique aux assistants médicaux, en passant par les appareils électroménagers pour maisons intelligentes, les objets IdO évoluent dans une pléthore de domaines d'application. Cependant, les avantages qu'ils peuvent apporter à notre société augmentent conjointement avec leurs implications en matière de vie privée. Communiquant continuellement de précieuses informations par le biais de liaisons non filaires telles que le Bluetooth et le Wi-Fi, ces appareils connectés accompagnent leurs propriétaires dans leurs activités. La plupart du temps émises sur des canaux ouverts, et parfois en l'absence de chiffrement, ces informations sont alors facilement accessibles pour tout attaquant passif à portée. Dans cette thèse, nous explorons deux problèmes de vie privée majeurs résultant de l'expansion de l'IdO et de ses communications sans fil : le traçage physique et l'inférence d'informations utilisateurs. Sur la base de deux grands ensembles de données composés de signaux radio issus de périphériques Bluetooth/BLE, nous mettons d'abord en échec les fonctionnalités anti-traçage existantes avant de détailler plusieurs applications invasives pour la vie privée. En s'appuyant sur des attaques passives et actives, nous démontrons également que les messages diffusés contiennent des informations en clair allant des caractéristiques techniques des appareils aux données personnelles des utilisateurs telles que des adresses e-mail et numéros de téléphone. Dans un second temps, nous concevons des contre-mesures pratiques pour résoudre les problèmes de vie privée identifiés. Dans ce sens, nous fournissons des recommandations aux fabricants, et proposons une approche afin de vérifier l'absence de failles dans l'implémentation de leurs protocoles. Enfin, dans le but d'illustrer davantage les menaces de vie privée enquêtées, nous implémentons deux démonstrateurs. Par conséquent, Venom introduit un système de traçage physique visuel et expérimental, tandis qu'Himiko propose une interface humaine permettant d'inférer des informations sur les appareils IdO et leurs propriétairesAlso known as the Internet of Things (IoT), the proliferation of connected objects offers unprecedented opportunities to consumers. From fitness trackers to medical assistants, through smarthome appliances, the IoT objects are evolving in a plethora of application fields. However, the benefits that they can bring to our society increase along with their privacy implications. Continuously communicating valuable information via wireless links such as Bluetooth and Wi-Fi, those connected devices support their owners within their activities. Most of the time emitted on open channels, and sometimes in the absence of encryption, those information are then easily accessible to any passive attacker in range. In this thesis, we explore two major privacy concerns resulting from the expansion of the IoT and its wireless communications: physical tracking and inference of users information. Based on two large datasets composed of radio signals from Bluetooth/BLE devices, we first defeat existing anti-tracking features prior to detail several privacy invasive applications. Relying on passive and active attacks, we also demonstrate that broadcasted messages contain cleartext information ranging from the devices technical characteristics to personal data of the users such as e-mail addresses and phone numbers. In a second time, we design practical countermeasures to address the identified privacy issues. In this direction, we provide recommendations to manufacturers, and propose an approach to verify the absence of flaws in the implementation of their protocols. Finally, to further illustrate the investigated privacy threats, we implement two demonstrators. As a result, Venom introduces a visual and experimental physical tracking system, while Himiko proposes a human interface allowing to infer information on IoT devices and their owners
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Lu, Yong. "THE DIFFUSION OF WIRELESS INTERNET TECHNOLOGY AMONG UNIVERSITY FACULTY MEMBERS". Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1140660624.
Testo completo
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Gao, Qiang. "Connection tree based mobility management for wireless internet access networks /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3022208.
Testo completo
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Ramezani, Parisa. "Extending Wireless Powered Communication Networks for Future Internet of Things". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/16850.
Testo completoAbstract (sommario):
Energy limitation has always been a major concern for long-term operation of wireless networks. With today's exponential growth of wireless technologies and the rapid movement towards the so-called Internet of Things (IoT), the need for a reliable energy supply is more tangible than ever. Recently, energy harvesting has gained considerable attention in research communities as a sustainable solution for prolonging the lifetime of wireless networks. Beside conventional energy harvesting sources such as solar, wind, vibration, etc. harvesting energy from radio frequency (RF) signals has drawn significant research interest in recent years as a promising way to overcome the energy bottleneck. Lately, the integration of RF energy transfer with wireless communication networks has led to the emergence of an interesting research area, namely, wireless powered communication network (WPCN), where network users are powered by a hybrid access point (HAP) which transfers wireless energy to the users in addition to serving the functionalities of a conventional access point. The primary aim of this thesis is to extend the baseline model of WPCN to a dual-hop WPCN (DH-WPCN) in which a number of energy-limited relays are in charge of assisting the information exchange between energy-stable users and the HAP. Unlike most of the existing research in this area which has merely focused on designing methods and protocols for uplink communication, we study both uplink and downlink information transmission in the DH-WPCN. We investigate sum-throughput maximization problems in both directions and propose algorithms for optimizing the values of the related parameters. We also tackle the doubly near-far problem which occurs due to unequal distance of the relays from the HAP by proposing a fairness enhancement algorithm which guarantees throughput fairness among all users.
30
Olsson, Alexander. "Meshnetwork of wireless IoT sensors". Thesis, Umeå universitet, Institutionen för fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-122908.
Testo completoAbstract (sommario):
The Internet of things is a scenario where devices such as lighting, household appliances, sensors etc. are connected and communicate with each other via Internet. This puts a demand for a good infrastructure around these devices. One way to handle this is to use radio as a means of communication and let the devices forward each other's traffic in what is known as a mesh network. This thesis explores different radio standards that can be used to create a mesh network for sensors. Two different approaches to mesh networking using Bluetooth Low Energy was implemented and evaluated. One approach works by letting all devices broadcast every message they receive, a rather brute force approach. The other approach worked by letting the network find routes between all the nodes in the network and then establishes a connection between the nodes that want to communicate via intermediate nodes. It was found that the rebroadcast approach in idle mode used 3.36 mAh while the connection approach used 0.47 mAh for the same configuration. Another test was performed where the percentage of successfully delivered messages was measured. For the rebroadcast approach it was 75 % and for connection it was 58 %. Tweaking the connection network to not be able to adapt to changes increased the throughput to 77 %. During the testing numerous ways for improving performance were thought of but not implemented. The need for synchronizing the devices clocks and establishing protocol for when to send and receive became apparent when working with the rebroadcast network. In the connection network there were problems with that the routing maintenance led to unavailable units and reduced performance.Sakernas internet, Internet of Things är ett scenario där elektriska apparater så som belysning, hushållsmaskiner, sensorer mm är anslutna och kommunicerar med varandra via internet. Men så många anslutna enheter ställer stora krav på infrastrukturen kring enheterna. Ett sätt att lösa problemen kring infrastruktur är att låta enheterna kommunicera via radio och låta dem vidarebefordra varandras datatrafik i en typ av nätverkstopologi som kallas för meshnätverk. Det här examensarbetet utforskar möjliga radiostandarder som kan användas för att skapa ett meshnätverk för just sensorer. Två typer av meshnätverk implementerades med Bluetooth Low Energy och deras styrkor och svagheter utvärderades. En av dessa gick ut på att enheterna i nätverket sände ut meddelanden som alla kunde ta och sedan att de som lyckades ta emot i sin tur sände meddelandena vidare. Det är en enkel metod som är lätt att implementera.Den andra metoden gick ut på att nätverket tog reda på sin konfiguration och vilken rutt som ska tas via andra enheter för att nå den man vill. När enheterna sen vill kommunicera så upprättar de en anslutning via enheterna längs rutten. Två saker som jämfördes mellan metoderna var strömförbrukning och andel lyckade sändningar. För samma nätverk så drog återsändnings nätverket 3.36 mA och anslutningsnätverket 0.47 mA. Antalet lyckade sändningar testades i ett annat scenario och där kom 75 % av meddelanden i återsändningsnätverket fram och motsvarande siffra för anslutningsnätverket var 58\%. Vidare testades det att stänga av utbytet av rutt information och sökningar efter nya enheter i anslutningsnätverket och då kom 77 % av meddelanden fram. I återsändningsnätverket insåg man att det fanns ett behov av att synkronisera klockorna i enheterna och etablera ett protokoll för hur när man ska sända och ta emot.I anslutningsnätverket så uppstod problem med att enheterna blev otillgängliga när de synkroniserade sin konfiguration vilket ledde till försämrad prestanda.
31
Tian, Jun. "A speed adaptive mobile Internet protocol over wireless local area network". [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012700.
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Meeran, Mohammad Tariq. "An analysis of voice over Internet Protocol in wireless mesh networks". Thesis, University of the Western Cape, 2012. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_8735_1370594169.
Testo completoAbstract (sommario):
This thesis presents an analysis of the impact of node mobility on the quality of service for voice over Internet Protocol in wireless mesh networks. Voice traffic was simulated on such a mesh
network to analyze the following performance metrics: delay, jitter, packet loss and throughput. Wireless mesh networks present interesting characteristics such as multi-hop routing, node mobility, and variable coverage that can impact on quality of service. A reasonable deployment scenario for a small organizational network, for either urban or rural deployment, is considered with three wireless mesh network scenarios, each with 26 mesh nodes. In the first scenario, all mesh nodes are stationary. In the second scenario, 10 nodes are mobile and 16 nodes are stationary.
Finally, in the third scenario, all mesh nodes are mobile. The mesh nodes are simulated to move at a walking speed of 1.3m per second. The results show that node mobility can increase packet
loss, delay, and jitter. However, the results also show that wireless mesh networks can provide acceptable quality of service, providing that there is little or no background traffic generated by other
applications. In particular, the results demonstrate that jitter across all scenarios remains within humanacceptable tolerances. It is therefore recommended that voice over Internet Protocol implementations on wireless mesh networks with background traffic be supported by quality of service standards
otherwise they can lead to service delivery failures. On the other hand, voice-only
esh networks, even with mobile nodes, offer an attractive alternative voice over Internet Protocol platform.
33
Henton, Glen C. Swick Justin R. "Extending the tactical wireless internet in support of USMC Distributed Operations". Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://bosun.nps.edu/uhtbin/hyperion.exe/06Sep%5FHenton.pdf.
Testo completoAbstract (sommario):
Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, September 2006.Thesis Advisor(s): Carl Oros, Rex Buddenberg. "September 2006." Includes bibliographical references (p. 83-86). Also available in print.
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Kaynar, Kerem. "Developing A Zigbee Wireless Network And Controlling It Through The Internet". Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610583/index.pdf.
Testo completoAbstract (sommario):
The aim of this thesis is to develop a network, whose nodes communicate with the ZigBee wireless network protocol, and control this network with a PC through the Internet. One of the nodes of this network is designed to be master node. The other
nodes are slave nodes. The master node can be connected to an Ethernet connected to the Internet. A PC can communicate with the master node via a specific web application over the Internet. The communication between a web server, in which the specific web application is loaded, and the master node is performed using a specific application protocol working over TCP/IP and defined in this thesis. The master node controls the slave nodes of the wireless network formed according to the commands given by the user of a PC over the Internet. The master node contains an implementation of the ZigBee stack along with a suitable application software to communicate with the slave nodes. The master node also contains an implementation of the TCP/IP stack along with a suitable application software to communicate with a web server in which the specific web application is loaded. The slave nodes contain an implementation of the ZigBee stack along with a suitable application software to communicate with the master node. For each type of node, appropriate hardware which is compliant with the software contained by that type of node is used. Each type of node uses microcontroller-based hardware.
35
Aitken, D. G. "Error control coding for mixed wireless and internet packet erasure channels". Thesis, University of Surrey, 2008. http://epubs.surrey.ac.uk/804436/.
Testo completoAbstract (sommario):
Recent years have seen dramatic growth in Internet usage and an increasing convergence between Internet and wireless communications. There has also been renewed interest in iteratively decoded low-density parity-check (LDPC) codes due to their capacity approaching performance on AWGN channels.
36
Ewald-Arostegui, Nimbe Leonor. "Transport Control Protocol Optimisation over Wireless Internet: a Cross-Layer Approach". Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487513.
Testo completoAbstract (sommario):
This thesis presents an analytical model of a cross-layer communication system to enable improvement in the Transport Control Protocol (rCP) over mixed wired and wireless Internet. The focus is on the quantitative performance evaluation of the interactions between TCP and a hybrid Automatic Repeat reQuest protocol (HARQ) in the link layer (LL) with a finite buffer size. TCP evolution is described and a review of the different approaches to im/ r prove its performance is given. A survey of the most relevant TCP analytical proposals is also provided. The operation of a HARQ scheme comprising Forward Error CorreCtion (FEC) convolutional codes and a Selective Repeat (SR) ARQ protocol is analytically charac~erised by a Discrete Time Markov Chain (DTMC). Corruption losses occur in a radio channel and are modelled by a two-state DTMC whilst congestive losses are due to an LL finite buffer size. HARQ performance parameters are computed through the twO-moment approximation of an M/G/K/l analysis. The accuracy and correctness of the HARQ model is assessed as well as its adequacy for multimedia applications. All analytical results are validated through the well known network simulator, ns-2. It is shown that performance improvemen~ is achieved by dynamically selecting optimal HARQ parameters. It is also illustrated that HARQ can provide the required 'QoS as well as reliable transfer to multimedia applications only under certain power' and traffic conditions given that the impact of congestive losses is greater as the transmission quality improves. An existing mathematical representation of TCP Reno is extended in order to model TCP NewReno given its better performance over noisy channels, Continuous Time Markov Chains (CTMC) are used to this end. The NewReno model accuracy is also validated. .A cross-layer TCP-HARQ communication system is developed with these two analytical models. Top down e>.:plicit notification from TCP to HARQ takes place. The advertised TCP state variables are passed to the LL entity which is able to predict NewReno performance and select the optimal HARQ ,. values. These predictions are computed through fixed-point approximations. The joint TCP-HARQ analytical model is validated and its correctness is demonstrated as well as its capacity to provide a significant TCP performance improvement through the selection of HARQ optimal parameters. It is also demonstrated that smaller LL buffer sizes than the typical size provide similar TCP throughput whilst higher buffer capacities do not represent significant performanc'e improvement. LL buffer capacity reduction mainly depends on the quality of the transmission over the radio channel.
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Petäjäjärvi, J. (Juha). "Low-power wireless communications in the Internet of Things:solutions and evaluations". Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526219196.
Testo completoAbstract (sommario):
Abstract The Internet of Things (IoT) is already providing solutions to various tasks related to monitoring the environment and controlling devices over wired and wireless networks. It is estimated by several well-known research facilities that the number of IoT devices will be in the order of tens of billions by 2020. This inevitably brings challenges and costs in deployment, management, and maintenance of networks. The focus of this thesis is to provide solutions that mainly help in the deployment and maintenance of various wireless IoT networks. Different applications have different requirements for a wireless link coverage. It is important to utilize suitable radio technology for a particular application in order, e.g., to maximize the lifetime of a device. A wireless body area network (WBAN) typically consists of devices that are within couple of meters from each other. The WBAN is suitable for, e.g., measuring muscle activity and transferring data to a storage for processing. The wireless link can use air as a medium, or alternatively, an induced electric field to a body can be used. In this thesis, it is shown that a location of the electrodes in the body have impact to the attenuation. Home automation IoT applications are typically implemented with mid-range wireless technologies, known as wireless personal area networks (WPAN). In order to minimize and get rid of battery change operations, a wake-up receiver could be utilized in order to improve the device’s energy efficiency. The concept is introduced and performance of the current state-of-the-art works are presented. In addition, a control loop enabling a passive device to have control over an energy source is proposed. Applications that have low bandwidth requirements can be implemented with low-power wide area networks (LPWAN). One technology – LoRaWAN – is evaluated, and it is recommended as based on the results to use it in non-critical applicationsTiivistelmä Esineiden internet (Internet of Things, IoT) mahdollistaa jo laajan kirjon erilaisia ratkaisuja ympäristön monitorointiin ja laitteiden hallintaan hyödyntäen sekä langattomia että langallisia verkkoja. Usea hyvin tunnettu tutkimusorganisaatio on arvioinut, että vuonna 2020 IoT laitteiden määrä tulee olemaan kymmenissä miljardeissa. Se luo väistämättä haasteita laitteiden sijoittamisessa, hallinnassa ja kunnossapidossa. Tämä väitöskirja keskittyy tarjoamaan ratkaisuja, jotka voivat helpottaa langattomien IoT laitteiden sijoittamisessa ja kunnossapidossa. IoT sovellusten laaja kirjo vaatii erilaisia langattomia radioteknologioita, jotta sovellukset voitaisiin toteuttaa, muun muassa, mahdollisimman energiatehokkaasti. Langattomassa kehoverkossa (wireless body area network, WBAN) käytetään usein hyvin lyhyitä langattomia linkkejä. WBAN on soveltuva esimerkiksi lihasten aktiivisuus mittauksessa ja mittaustiedon siirtämisessä talteen varastointia ja prosessointia varten. Linkki voidaan toteuttaa käyttäen ilmaa rajapintana, tai vaihtoehtoisesti, kehoa. Tässä työssä on näytetty, että käytettäessä kehoa siirtotienä, elektrodien sijainnilla on merkitystä signaalin vaimennuksen kannalta. Kotiautomaatio IoT sovellukset ovat tyypillisesti toteutettu käyttäen langatonta likiverkkoa, jossa linkin pituus sisätiloissa on alle 30 metriä. Jotta päästäisiin eroon pariston vaihto-operaatiosta tai ainakin vähennettyä niiden määrää, herätevastaanotinta käyttämällä olisi mahdollista parantaa laitteiden energiatehokkuutta. Herätevastaanotin konsepti ja tämänhetkistä huipputasoa edustavien vastaanottimien suorituskyky ovat esitetty. Lisäksi, on ehdotettu menetelmä joka takaa energian saannin passiiviselle IoT laitteelle. IoT sovellukset jotka tyytyvät vähäiseen kaistanleveyteen voidaan toteuttaa matalatehoisella laajan alueen verkolla (low-power wide area network, LPWAN). Yhden LPWAN teknologian, nimeltään LoRaWAN, suorituskykyä on evaluoitu. Tulosten perusteella suositus on hyödyntää kyseistä teknologiaa ei-kriittisissä sovelluksissa
38
Zulu, Docas Dudu. "Packet aggregation for voice over internet protocol on wireless mesh networks". Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4403.
Testo completoAbstract (sommario):
>Magister Scientiae - MScThis thesis validates that packet aggregation is a viable technique to increase call capacity for Voice over Internet Protocol over wireless mesh networks. Wireless mesh networks are attractive ways to provide voice services to rural communities. Due to the ad-hoc routing nature of mesh networks, packet loss and delay can reduce voice quality. Even on non-mesh networks, voice quality is reduced by high overhead, associated with the transmission of multiple small packets. Packet aggregation techniques are proven to increase VoIP performance and thus can be deployed in wireless mesh networks. Kernel level packet aggregation was initially implemented and tested on a small mesh network of PCs running Linux, and standard baseline vs. aggregation tests were conducted with a realistic voice traffic profile in hop-to-hop mode. Modifications of the kernel were then transferred to either end of a nine node 'mesh potato' network and those tests were conducted with only the end nodes modified to perform aggregation duties. Packet aggregation increased call capacity expectedly, while quality of service was maintained in both instances, and hop-to-hop aggregation outperformed the end-to-end configuration 4:1. However, implementing hop-to-hop in a scalable fashion is prohibitive, due to the extensive kernel level debugging that must be done to achieve the call capacity increase. Therefore, end-to-end call capacity increase is an acceptable compromise for eventual scalable deployment of voice over wireless mesh networks.
39
Swick, Justin R. "Extending the tactical wireless internet in support of USMC Distributed Operations". Thesis, Monterey, California. Naval Postgraduate School, 2006. http://hdl.handle.net/10945/2523.
Testo completoAbstract (sommario):
"This thesis will research, examine, and propose a Tactical Wireless Network infrastructure Concept of Operations in Support of Distributed Operations. Research and analysis will include the capabilities and performance characteristics of the 802.16 equipment currently implemented as part of the Marine Corps Tactical Command and Control Architecture in support of Operation Iraqi Freedom. Current Distributed Operations doctrinal capabilities will be compared to a proposed Concept of Operations that incorporates the most current state of the art wireless technologies to maximize both capability and interoperability. The method for evaluation will incorporate COTS products and Marine Corps tactical communications devices installed and operated in both a laboratory setting as well as a tactical field environment. Key performance metrics captured include equipment throughput capacity, communications bandwidth, range and distance limitations, power consumption, communications security, and transmission security. Additional metrics evaluated include level of equipment operational complexity and degree of interoperability with current USMC command and control architecture."-- p. i.
40
Valverde, Lionel J., e Romelo B. Nafarrette. "Secure wireless handoff". Thesis, Monterey, California. Naval Postgraduate School, 2003. http://hdl.handle.net/10945/943.
Testo completoAbstract (sommario):
Approved for public release, distribution is unlimitedWith the rapidly growing demand for portable devices such as laptops, handheld computers and Personal Digital Assistants (PDAs) with wireless networking capabilities, the need for reliable wireless data network communication has also increased. Just like in mobile voice communication, users demand uninterrupted, secure wireless data communication as they move from place to place. Mobile IP satisfies some of these demands - it enables mobile devices with fixed IP addresses to be permanently reachable even as their point of attachment to the network changes. This allows for routing of data packets to and from the mobile device irrespective of its location on the network. While uninterrupted data flow can be achieved with Mobile IP, it introduces additional security vulnerabilities, including data privacy, data integrity and authentication. The goal of this thesis is to investigate such vulnerabilities and explore implementations to overcome them.
Civilian, National Science Foundation
41
Kingsley, Chris. "City of narrowing shoulders and big ideas technology and politics in Philadelphia /". Diss., Connect to the thesis, 2005. http://thesis.haverford.edu/142/01/2005KingsleyC.pdf.
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Huang, Raymond. "A comparative study of mobile internet deployment models in New Zealand a thesis submitted to Auckland University of Technology in partial fulfillment of the requirements for the degree of Master of Computer and Information Sciences (MCIS), June 2007". Click here to access this resource online, 2007. http://repositoryaut.lconz.ac.nz/theses/1362/.
Testo completoAbstract (sommario):
Thesis (MCIS - Computer and Information Sciences) -- AUT University, 2007.Primary supervisor: Krassie Petrova. Includes bibliographical references. Also held in print (185 leaves : ill. ; 30 cm.) in City Campus Theses Collection (T 004.6 HUA)
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Silva, Veridiano António Fernandes de Carvalho e. "Soluções wireless/VoIP para redes comunitárias". Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3615.
Testo completoAbstract (sommario):
Mestrado em Engenharia de Computadores e TelemáticaNas últimas décadas, a evolução das novas Tecnologias de Informação e Comunicação (TIC), contribuiu em larga escala para o crescimento da Internet e da utilização massificada das tecnologias de banda larga. Com essa evolução, surgiram novas formas de comunicar recorrendo a tecnologias inovadoras, baseadas no protocolo IP (Internet Protocol). Contudo, surgiram assim os softphones, que são as primeiras aplicações da tecnologia VoIP, que vieram revolucionar a forma de comunicar, com custos substancialmente reduzidos, que causaram um enorme impacto nas pessoas e nas organizações. Com o presente trabalho, pretende-se elaborar um estudo minucioso das tecnologias VoIP, apresentando algumas soluções de implementação de um sistema de comunicações VoIP para uma rede comunitária de banda larga. Por último, será apresentada uma proposta de arquitectura, descrevendo os possíveis cenários de implementação de um fornecedor de comunicações VoIP numa Mesh network de rede comunitária.
In latest decades, the evolution of new Information and Communication Technologies (ICT) has contributed a large scale for the growth of the Internet and use mass of broadband technologies. With these developments, there were new ways to communicate using innovative technologies, based on the protocol IP (Internet Protocol). However, emerged as the softphone, which are the first applications of the technology VoIP, who came to revolutionize the way of communicating, with costs substantially reduced, which caused a huge impact on people and organizations. With this work, it is intended to prepare a detailed study of the technology VoIP, providing some solutions for implementing a communication system to a VoIP network of community broadband. Finally, will be a proposal for architecture, describing the possible scenarios for implementing a VoIP provider of communications network in a mesh network community.
44
KALYONCU, Samet. "Wireless Solutions and Authentication Mechanisms for Contiki Based Internet of Things Networks". Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-27158.
Testo completoAbstract (sommario):
Internet of Things, is a new expression described as the future of the internet, promises a new world surrounded by tiny smart objects interacting with the environment, communicating with each other, and controlled over internet. Investigating which low power wireless solution and authentication mechanism fits best for IoT networks, and applying these technologies on simulator and real hardware is the main task of this project. Bluetooth Low Energy, ANT, 6LoWPAN and ZigBee are investigated low power wireless technologies which might be used to create an IoT network. Yet, BLTE and ANT have narrower application areas compared to the others, therefore ZigBee and 6LoWPAN technologies are investigated in depth and compared as the 2 promising solutions for implementation and integration of Internet of things concept. SPINS, TinySec, TinyECC, SenSec, MiniSec, ContikiSec and AES CCM are the main security frameworks especially designed for wireless sensor networks providing confidentiality, authentication and integrity. These frameworks were described and compared to find out most suitable authentication mechanism for IoT networks. Contiki OS is used as the operating system of nodes during the implementation of network both on simulator Cooja and real hardware. ZigBee and 6LoWPAN were compared considering interoperability, packet overhead, security and availability. As a result 6LoWPAN came forward due to providing high interoperability and slightly less packet overhead features. ZigBee devices require extra hardware to operate with different technologies. Among the discussed security frameworks, ContikiSec and AES CCM were highlighted because of flexibility, providing different levels of security. Resource limited characteristic and diversity of IoT applications make flexibility a very useful feature while implementing a security framework. Experiments committed to implement a working IoT network were not hundred percent successful. 6LoWPAN was successfully implemented but implementation of the security framework was failed due to compatibility issues between the sensor and the router node. Firmware of the sensor node is not designed to provide any kind of security, therefore security features of the router node is also disabled.
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Yang, Chengchen. "CYBER-PHYSICAL SYSTEM: REAL-TIME INTERNET-BASED WIRELESS STRUCTURAL HEALTH MONITORING SYSTEM". OpenSIUC, 2009. https://opensiuc.lib.siu.edu/dissertations/111.
Testo completoAbstract (sommario):
As the demands to monitor the health status of structures increase, researchers around the world have proposed several concepts to solve this issue. This research first examines the existing technologies and then works toward a novel structural health monitoring solution. A comprehensive discussion includes major topics from sensor selection and installation to sensing data display. A cyber-physical system combining embedded system, wireless communication, and the Java platform was developed for structural health monitoring. The focus of this system is to continuously monitor structural response and broadcast the information to users worldwide via the Internet. A wireless sensor node is designed to connect up to eight sensor channels. Various sensors have been tested on the sensor node. A data acquisition and repository system was also developed. The use of the Java language makes this system capable of running in virtually any existing computer platform. Distributed design concept expands its functionalities and capabilities. Its graphical user interface offers users a friendly and ease-of-use environment to monitor real-time and historical data in both graphical and numerical ways. Every component of the system has been validated to verify its functionality. Additionally, the whole system has been implemented on a steel pedestrian bridge to observe its performance.
46
Nawaz, Omer. "Secure Identification in Social Wireless Networks". Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4042.
Testo completoAbstract (sommario):
The applications based on social networking have brought revolution towards social life and are continuously gaining popularity among the Internet users. Due to the advanced computational resources offered by the innovative hardware and nominal subscriber charges of network operators, most of the online social networks are transforming into the mobile domain by offering exciting applications and games exclusively designed for users on the go. Moreover, the mobile devices are considered more personal as compared to their desktop rivals, so there is a tendency among the mobile users to store sensitive data like contacts, passwords, bank account details, updated calendar entries with key dates and personal notes on their devices. The Project Social Wireless Network Secure Identification (SWIN) is carried out at Swedish Institute of Computer Science (SICS) to explore the practicality of providing the secure mobile social networking portal with advanced security features to tackle potential security threats by extending the existing methods with more innovative security technologies. In addition to the extensive background study and the determination of marketable use-cases with their corresponding security requirements, this thesis proposes a secure identification design to satisfy the security dimensions for both online and offline peers. We have implemented an initial prototype using PHP Socket and OpenSSL library to simulate the secure identification procedure based on the proposed design. The design is in compliance with 3GPP’s Generic Authentication Architecture (GAA) and our implementation has demonstrated the flexibility of the solution to be applied independently for the applications requiring secure identification. Finally, the thesis provides strong foundation for the advanced implementation on mobile platform in future.
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Hui, Chui Ying. "Broadcast algorithms and caching strategies for mobile transaction processing". HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/781.
Testo completo
48
Huang-Fu, Chien-Chun, e 皇甫建君. "iSOHO:A Wireless Internet Service". Thesis, 1997. http://ndltd.ncl.edu.tw/handle/27748486008868142227.
Testo completoAbstract (sommario):
碩士國立交通大學
資訊工程系
89
Short Message Service (SMS) has become one of the most popular wireless services. Recently, most modern digital mobile phone systems offer SMS as a profitable added-value service. In this paper, we introduce iSOHO wireless service platform based on iSMS Gateway architecture. With this platform, many Internet applications can be run through SMS. For example, users can control their home appliances and access information and services from Internet by using SMS anytime and anywhere.
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Abd-Alhameed, Raed A., Jonathan Rodriguez, B. A. L. Gwandu, Peter S. Excell, Mohammad J. Ngala e Abubakar S. Hussaini. "Green Wireless Internet Technology". 2014. http://hdl.handle.net/10454/8534.
Testo completoAbstract (sommario):
YesIET Editorial: In the future communications will be pervasive in nature, allowing users access at the “touch of button” to attain any service, at any time, on any device. The future device design process requires both a reconfigurable RF front end and back end with high tuning speed, energy efficiency, excellent linearity and intelligence to maximise the “greenness” of the network. But energy efficiency and excellent linearity are the main topics that are driving the designs of future transceivers, including their efforts to minimise network contributions to climate changes such as the effect of CO2 emissions: the minimisation of these is a requirement for information and communication technology (ICT) as much as for other technologies. Recently, information and communication technologies were shown to account for 3% of global power consumption and 2% of global CO2 emissions, and hence far from insignificant. The approach towards energy conservation and CO2 reduction in future communications will require a gret deal of effort which should be targeted both at the design of energy efficient, low-complexity physical, MAC and network layers, while maintaining the required Quality of Service (QoS). There is also a need, in infrastructures, networks and user terminals, to take a more holistic approach to improving or achieving green communications, from radio operation, through functionality, up to implementation. The increasing demand for data and voice services is not the only cause for concern since energy management and conservation are now at the forefront of the political agenda. The vision of Europe 2020 is to become a smart, sustainable and inclusive economy, and as part of these priorities the EU have set forth the 20:20:20 targets, whereby greenhouse gas emissions and energy consumption should be reduced by 20% while energy from renewables should be increased by 20%.
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Cheng, Chieh-Wen, e 鄭傑文. "Mobility Support in Wireless Internet". Thesis, 1999. http://ndltd.ncl.edu.tw/handle/22236186756169085629.
Testo completoAbstract (sommario):
博士國立清華大學
資訊工程學系
87
Wireless networks are usually composed of a wired backbone and one or more hops connecting mobile hosts to the wired part. Our research deals with the mobility management scheme for Mobile Wireless InterNet (MWIN). MWIN is a wireless service network wherein its core network consisting of Internet routers and its access network can be built from any Internet-capable radio network. In our research, we inspect two mobility issues of MWIN. At first, we address the handoff problems in the wireless part of MWIN. Next, we discuss the mobility support in the backbone networks which interconnect the wireless access networks. Currently, two major standards are available for MWIN, i.e., the Mobile IP and wireless LAN. Mobile IP solves address mobility problem with the Internet protocol while wireless LAN provides a wireless Internet access in the local area. However, these two schemes solve problems independently at different layers, thereby some additional problems occur, e.g., delayed handoff, packet loss, and inefficient routing. We will identify these new problems and performs analyses on the handoff within MWIN. Then, a new handoff architecture that extends the features of both mobile IP and wireless LAN handoff mechanism is proposed. This new architecture consists of Mobile IP extensions and a modified wireless LAN handoff algorithm. The effect of this enhancement provides a linkage between different layers for preventing packet loss and reducing handoff latency. For the wired backbone network of MWIN, we consider to use the label switching networks to connect the wireless access networks. We address the problems of adding mobility support to label switching networks. Based on the simple and efficient label switching technology, we design a rerouting scheme to redirect the IP flow into shortest path route to mobile nodes. This scheme is compatible with the existing IP and Mobile IP protocols. Using the proposed rerouting scheme, route optimization can be accomplished. Moreover, IP traffic transmitted through label switching networks experience less delay.