While WiFi-based indoor localization is attractive, the need for a significant degree of pre-deployment effort is a key challenge. In this paper, indoor localization with no pre-deployment effort in an indoor space, such as an office building corridor, with WiFi coverage but no apriori knowledge of the placement of the access points(APs) is implemented for mobile devices. WiFi Received Signal Strength(RSS) in the considered environment is used to build radio maps using WiFi fingerprinting approach. Two architectures are developed based on this localization algorithm. The first one involves a client-server approach where the localization algorithm runs on the server whereas the second one is a standalone architecture and the algorithm runs on the SD card of the mobile device.

Denna rapport innefattar en genomgång av den nya 802.11ax (WIFI6)-standarden med djupdykning och förklaringar på de nya funktionerna BSS Coloring, Target Wake Time och OFDMA med flera. Frågeställningen som presenteras är om det är en bra investering av små företag och hem-användareatt uppgradera sin utrustning till WIFI 6 kompatibel sådan.Efter genomgång av protokollet och de nya funktionerna så rekommenderas inte detta medmotiveringen att tekniken är för ny och antal enheter som mobil och laptops med standarden är iskrivande stund inte så många och de som finns kan kosta mycket att köpa och byta ut.Det görs även en undersökning av Medlefors Folkhögskola och där så upptäcks att kanalplaneringenär bristfällig och att det finns accesspunkter från två tillverkare som sänder samtidigt i lokalerna. Därför ges det ett förslag på uppgradering av samtliga enheter till WIFI 6-kompatibel sådan. Utrustningen som föreslås är av märket Ubiquiti och samtliga enheter föreslås att bytas ut.Slutligen diskuteras summeringen med att ytterligare tester på större nätverk måste göras för attfullt ut se att det som låter så bra i teorin också ska fungera vid skarp implementation på stora arenorfullsatt med folk, vilket framtiden får utvisa.

This master's thesis deals with security of wireless network standard 802.11. There are described security mechanisms as hide SSID, MAC address filtering, WEP, WPA, WPA2 protocols. There are described also the most often kinds of attacks (Denial of Service, disclosure WEP key, Man-in-the-Middle). The work contains investigation of used security mechanisms in wireless networks in parts of Brno. There were used NetStumbler and inSSIDer applications for this measurement. The last part of work contains measurement of security mechanisms (WEP, WPA, WPA2) effect to transfer rate from the point of view of the end user. The measurement was realized with Iperf application.

Objective of this thesis is to point out to almost everywhere present flaw in realization of second level network security access to WiFi networks with using traffic tunneling over DNS protocol. Realization has been accomplished by existing utilities OzymanDNS, DNS2TCP, NSTX, Iodine, Heyoka. Measurements were done on realistic traffic on the network. The effort was to show outline of these implementations. Transfer speeds in some implementations can be marked as applicable thanks to high speeds, which are on the same level as broadband internet. Functionality was tested on WiFi network, where was also compromised PPTP VPN tunnel, its function was to provide security of the communication on wireless network due to absence of first level security mechanisms such as WPA, WPA 2 and so on, with the help of Asleap, which comes out of Cisco LEAP attack. At the end of the work are suggested possible countermeasures for securing network by the topology change of the network infrastructure or by implementing IDS.

Buffer sizing is an important network configuration parameter that impacts the quality of data traffic. Falling memory cost and the fallacy that ‘more is better’ lead to over provisioning network devices with large buffers. Over-buffering or the so called ‘bufferbloat’ phenomenon creates excessive end-to-end delay in today’s networks. On the other hand, under-buffering results in frequent packet loss and subsequent under-utilization of network resources. The buffer sizing problem has been studied extensively for wired networks. However, there is little work addressing the unique challenges of wireless environment. In this dissertation, we discuss buffer sizing challenges in wireless networks, classify the state-of-the-art solutions, and propose two novel buffer sizing schemes. The first scheme targets buffer sizing in wireless multi-hop networks where the radio spectral resource is shared among a set of con- tending nodes. Hence, it sizes the buffer collectively and distributes it over a set of interfering devices. The second buffer sizing scheme is designed to cope up with recent Wi-Fi enhancements. It adapts the buffer size based on measured link characteristics and network load. Also, it enforces limits on the buffer size to maximize frame aggregation benefits. Both mechanisms are evaluated using simulation as well as testbed implementation over half-duplex and full-duplex wireless networks. Experimental evaluation shows that our proposal reduces latency by an order of magnitude.

Freedom is human’s natural instinct, which was limited by Ethernet and Fixed Telephony Era. With the emergence of new technologies like wireless fidelity (WiFi) and voice over IP (VoIP) humans once again have freedom of movement; which at the very same time provides enough reasons to change the market dynamics of communication industry. The buzz of Voice over WiFi (VoWiFi) in recent years indicates that VoWiFi is shaping up as the next big challenge to traditional telephony, not only due to cost, but also due to range of services and amount of freedom it can offer. However, at the very same time these technologies have evolved to threaten the well-established telephony markets. Enterprise solutions for VoWiFi require enhanced security mechanism and seamless handovers. To address security related issues Wi-Fi Alliance in conjunction with IEEE introduced an enhanced and interoperable security scheme called WiFi Protected Access (WPA). Real time services are sensitive to latency, hence requiring bounded delay time throughout an ongoing session. Handovers in WiFi networks can take fairly long time which real time services cannot tolerate. The problem is further elevated when WiFi networks are secured by using WPA Enterprise. In this thesis we will examine the complete handoff process in WiFi networks. The impact of handovers on VoIP traffic will also be observed. Following the detailed analysis some suggestions will be presented concerning how to reduce this handoff latency. / Friheten som ligger i människans natur begränsades av Ethernet och den fasta telefonin. Med uppkomsten av nya teknologier så som Wireless Fidelity (WiFi) och Voice over IP (VoIP) återfår människan den en gång förlorade friheten. Samtidigt kommer telekommunikationsindustrin att kunna ändras till sin struktur genom WiFi och VoIP. Integreringen av Voice over IP och WiFi , även mer känd som Voice over WiFi, (VoWiFi) har under senare år indikerat att det är en potentiell utmanare till traditionell telefoni inte bara ur ett kostnadsperspektiv utan också för att denna teknologi medför ökade möjligheter när det gäller nya tjänster. Dock återstår en del arbete för VoWiFi för att kunna rubba den fasta telefonin. Företagslösningar av denna teknologi kräver att säkerhetsaspekterna ses över dessutom måste seamless handover fungera på ett tillfredställande sätt. För att se över säkerhetsaspekterna har Wi-Fi Alliance i samarbete med IEEE introducerat säkehetsmekanismen WiFi Protected Access (WPA). Realtidstjänster är känsliga mot fördröjningar. Handover i ett WiFi nätverk kan ta relativt lång tid vilket är oacceptabelt för realtidstjänster. Problemet blir än mer påtagligt när WiFi-nätet är säkrat med hjälp av WPA. I denna exjobbsrapport kommer handoff processen för WiFi nätverk att behandlas. Effekten av handover för VoIP trafik kommer också att beskrivas. Resultat och analyser kommer att föreslås för hur man kan reducera handoff-fördröjningar.

IEEE 802.11 (WiFi) only has two modes of trust--complete trust or complete untrust. The lack of nuance leaves no room for sensors that a user does not fully trust, but wants to connect to their network, such as a WiFi sensor. Solutions exist, but they require advanced knowledge of network administration. We solve this problem by introducing a new way of modulating data in the latency of the network, called Latency Shift Keying. We use specific characteristics of the WiFi protocol to carefully control the latency of just one device on the network. We build a transmitter, receiver, and modulation scheme that is designed to encode data in the latency of a network. We develop an application, Wicket, that solves the WiFi trust issue using Latency Shift Keying to create a new security association between an untrusted WiFi sensor and a wired device on the trusted network. We evaluate its performance and show that it works in many network conditions and environments.

Inter-Vehicular Communication is an optimistic technology to enhance road safety. The wireless medium often used to exchange vital information. Wi-Fi is also used to share the information, but it required an access point hardware to communicate. Wi-Fi Direct enabled the device exchange information without a hardware access point. Over the last decades, the usage of wireless technology has been increased and transformed the way electronic devices interact and communicate. Wi-Fi Direct technology provides peer-to-peer communication. So, Wi-Fi is highly applicable for car-to-car communication because of its High data rate, range, standard usage. Within the framework of this thesis concept of prototyping car-to-car communication by using Wi-Fi Direct service in smartphones. Focus here to optimize resource utilization and to provide basic functionality within the programming mode.

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No. of bitstreams: 1 Dissertação - Atacílio Costa Cunha.pdf: 8225097 bytes, checksum: dff40e1008c70b9b5cc749b2a69d8958 (MD5) Previous issue date: 2014-05-09 / Não Informada / WiFi Location systems are increasingly present in our days because of the great ease that the devices can provide to users, such as mobility, independence of factors that limit and cause discomfort usability as cables, for example, and also be more convenient for the user to use something easy to handle. Apart from these points, it is known that the WiFi devices are increasingly developed, providing more opportunities for use in the routine of users. WiFi Location Systems perform device or people discovery in a given environment based on power signal measurements obtained by exchanging packets between devices that compose such systems. This paper proposes a Location WiFi method using multiple routers with directional antennas in the location environment. Routers with directional antennas are used in this study due to its ability to limit signal coverage for a given area, unlike systems with omnidirectional antennas. The impact that a packet sent by a device with unknown position generates in directional antennas installed at the location system can provide different RSSI values. Through the system offline stage where the training part is done, a database is created with all RSSI values obtained from each packet received by directional routers and positions from where the packages were sent. This database is used as knowledge for the classification algorithm so that it can estimate from where a package was sent, only based on RSSI values obtained at each directional router. Two classification algorithms were compared in this proposal to analyze the performance characteristics of each one in any location enviroment. They are the algorithms kNN and Naive Bayes, both widely used in the literature. During the the training part of the localization system composed by directional routers, it was also analyzed how to organize the routers to get results with greater location accuracy. Thus, it was possible to analyze the organization of the routers in the location environments, being together and pointing in different directions, and separated and focused to the center of the localization environment. ix Another important point of this proposal is the application of the localization system based on two types of location: Precise Location and Contextual Location. The precise location allows to estimate the exact position of a device in the axes x and y of a particular environment where it is installed. And the contextual location allows to estimate the position of a particular device based on the analysis of the context of the environment where it is inserted. All data collected during the experiments were analyzed and tested, and show that the system proposed in this paper can be used as a WiFi positioning system for indoor environments as an alternative to the system commonly found in the location literature, composed of omnidirectional routers. According to the structure of the location where the system was inserted and the organization of directional routers, it was possible to obtain very similar results compared to the location system composed by omnidirectional routers. This can be seen from the results obtained in a small location environment composed by the ICOMP laboratories where the system with directional routers and data classification from the kNN algorithm, has achieved 84.26% of accuracy in positioning compared with 83.93% achieved with directional routers together using the same classification algorithm. Another interesting point seen in the results of this work is that the use of Naive Bayes algorithm tends to be better when the system uses directional routers rather than omni-directional one. This happens because this algorithm can analyze as the direction of each antenna impacts the characteristics of signal reception in a given environment. This can be seen for example in the results obtained on a larger localization environment composed of ICOMP teachers rooms where the positioning system with scattered directional antennas got 80.16% accuracy in positioning estimation compared with the system composed by omnidirectional antennas that got 71.68%. Thus, we shall show that the tracking systems can be composed of directional routers as an alternative to the WiFi location conventional system. / Os sistemas de Localização WiFi estão cada vez mais presentes no nosso dia-a-dia devido à grande facilidade que os dispositivos utilizados nesta tecnologia podem proporcionar para os usuários, como mobilidade, independência de fatores que limitam e causam desconforto na usabilidade como cabos, por exemplo, e também por ser mais conveniente para o usuário utilizar algo de fácil manuseio. Além destes pontos, sabese que os dispositivos WiFi estão cada vez mais desenvolvidos, proporcionando mais possibilidades de uso no cotidiano dos usuários. Sistemas de Localização WiFi realizam a localização de dispositivos ou pessoas em um determinado ambiente com base em medições de potência de sinal, obtidas através da troca de pacotes entre os dispositivos que compõem tais sistemas. Neste trabalho é proposto um método de Localização WiFi utilizando múltiplos roteadores com antenas direcionais no ambiente de localização. Os roteadores com antenas direcionais são utilizados neste trabalho devido a sua capacidade de limitar a cobertura sinal para uma determinada área, diferente dos sistemas com antenas omnidirecionais. O impacto que um pacote enviado por um dispositivo com posição desconhecida gera nas antenas direcionais do sistema é capaz de proporcionar valores de RSSI diferentes. Através da fase offline do sistema onde é realizado a parte de treinamento, um banco de dados é criado com todos os valores de RSSI obtidos a partir de cada pacote recebido pelos roteadores direcionais e as posições de onde os pacotes foram enviados. Essa base de dados é utilizada como conhecimento para que o algoritmo de classificação possa estimar de onde um pacote foi enviado, somente com base nos valores de RSSI obtidos em cada roteador direcional. Foram comparados dois algoritmos de classifição nesta proposta como forma de analisar as características de comportamento de cada um deles nos ambientes de localização. São eles os algoritmos kNN e Naive Bayes, ambos bastante utilizados na literatura. Durante a experimentação do sistema de localização composto pelos roteadores direcionais, foi analisado também como organizar os roteadores para ser obter resultavii dos com maior precisão de localização. Desta forma, foi possível analisar nos ambientes de localização a organização dos roteadores unidos apontando para direções diferentes, e separados focados para o centro do ambiente de localização. Outro ponto importante desta proposta é a aplicação do sistema de localização com base em dois tipos de localização: Localização Precisa e Localização Contextual. A Localização Precisa permite estimar a posição exata de um dispositivo nos eixos x e y de um determinado ambiente onde ele está instalado. Já a Localização Contextual, permite estimar posição de um determinado dispositivo com base na análise do contexto do ambiente onde ele está inserido. Todos os dados obtidos durante os experimentos foram analisados e testados, e demonstram que o sistema proposto neste trabalho pode ser utilizado como sistema de localização WiFi para ambientes internos como alternativa do sistema comumente de localização encontrado na literatura, composto por roteadores omnidirecionais. Conforme a estrutura do ambiente de localização onde o sistema estava inserido e a organização dos roteadores direcionais foi possível obter resultados bem semelhantes ao do sistema de localização convecional composto por roteadores omnidirecionais. Isto pode ser visto nos resultados obtidos em um ambiente pequeno de localização composto pelos laboratórios do IComp onde, com roteadores direcionais e classifição de dados a partir do algoritmo kNN, foi possível obter 84,26% de precisão na localização comparada com 83,93% conseguida com roteadores direcionais juntos utilizando o mesmo algoritmo de classifição. Outro ponto interessante visto nos resultados deste trabalho é a utilização do algoritmo Naive Bayes tende a ser melhor para o sistema quando o mesmo utiliza roteadores direcionais ao invés de omnidirecionais, já que este algoritmo consegue analisar como o direcionamento de cada antena impacta nas características de recepção de sinal em um determinado ambiente. Isto pode ser visto por exemplo nos resultados obtidos em um ambiente maior de localização composto pelas salas de professores do IComp onde o sistema de localização com antenas direcionais espalhadas obteve 80,16% de precisão na estimativa de localização comparado com o sistema composto por antenas omnidirecionais que obteve 71,68%. Com isto, pretende-se mostrar que os sistemas de localização podem ser compostos por roteadores direcionais como alternativa para o sistema convecional de localização WiFi.

Šio darbo objektas – išmaniųjų telefonų pastovaus ryšio išlaikymas tarp WiFi adapterių. Dabartiniu momentu yra sukurta daug prieigos taškų paieškos sistemų, tačiau šios sistemos „nemoka“ automatiškai susirasti bei prisijungti prie tinkamiausio prieigos taško. Taip pat egzistuojančios sistemos ieškodamos prieigos taškų išeikvoja daug išmaniojo telefono energetinių resursų. Darbe įvardijami pagrindiniai egzistuojančių sistemų trūkumai ir analizuojamos tobulinimo galimybės panaudojant miglotąją logiką. Pirmojoje darbo dalyje aprašoma tyrimo sritis, objektas bei remiantis literatūros analize atskleidžiamas, per esamas bevielio interneto prieigos taškų paieškos sistemų problemas, temos aktualumas. Antroji dalis apima komponentų projektavimą bei programavimą. Projektavimui naudojama UML, Visio ir FuzzyTech įrankiai. Šioje dalyje yra pavaizduotos komponentų klasių, įvykių bei sekų diagramos, pateikta duomenų bazės schema bei miglotųjų įverčių diagramos. Šioje darbo dalyje yra sukuriama ir pati bevielio interneto prieigos taškų valdymo sistema „HandyWi“. Trečioje darbo dalyje pateikti naujai sukurtos „HandyWi“ sistemos kokybinių tyrimo duomenų palyginimo rezultatai. Pagrysta sukurtos sistemos reikšmė informacinių technologijų srityje. Paskutinėje darbo dalyje pateikta apibendrinta informacija apie sukurtą bevielio interneto prieigos taškų paieškos sistemos funkcionalumą ir išskirtinumą bei tolimesnes jos plėtojimo galimybes. Darbą iliustruoja 41 paveikslas, 9 lentelės ir terminų... [toliau žr. visą tekstą] / The object of this work is to keep stable communication between smart phone and wireless adapter. There are many created access points discovery systems at the moment, but those systems “don’t know” how to discovery and connect to suitable access point. Also existing systems have lost a lot of smart phone battery energy during discovering access points. The main existing systems issues and issues solving abilities by using fuzzy logic are presented at this work. The subject of research, object and subject relevance were detectable through literature analysis and through existing access point discovery systems issues are presented in the first part. The subject of research and object are presented in the first part of this work. Also, subject relevance is presented pursuant to literature analyze of wireless internet access point discovery system. Object components design and programming process are presented in the second part. UML, Visio and Fuzzytech programs are used for designing components. Events, sequence and class diagrams are viewed in this part, also this part contain database schema and fuzzy sets diagrams. The main wireless internet discovery system is created in this part. The system is called “HandyWi”. The “HandyWi” system is comparison with existing system and quality data results are stored in the third part. The conclusions of the work, automatic access point discovery system functionality, oneness and further development abilities are presented in last... [to full text]