This thesis deals with the security of wireless sensor networks, mainly of the industrial standard ZigBee. The aim of the work is to familiarize with the 802.15.4 standard and the ZigBee technology, especially with present methods of security in this field. I have also analysed the requirements for the security of this technology. Further aim of this work is the introduction of the ZigBee kit and description of the Microchip's ZigBee stack. Analysis of the stack is connected with practical test of security functions in the ZigBee laboratory.

This thesis describes the work process two (WP2) of a project led by the traffic administration in Stockholm to achieve the passengers' thermal comfort in traffic buses.  The purpose of this thesis is to design and implement a measurement system comprised in eight measurement position in a bus. Each position is able to transmit data using a wireless communication protocol, with a central unit collecting all the transmitted data taking into consideration the accuracy of the measurements and filtering out the incorrect data. In order to accomplish this, a literature study is conducted investigating different measurement methods for different parameters, different communication protocols were analysed as well to determine an appropriate communication protocol suitable for climate measurement in a bus environment with passengers present on board.  The output of the HVAC system is also required to help the traffic administration demonstrate the results of adjusting the temperature in the bus to reach the thermal comfort and how it led to saving energy. The system incorporates ZigBee , ESP32 microcontroller in the sender positions and a Raspberry pi operating as a central unit to collect data and store it in a file system providing an accurate data that will help the traffic administration achieve their goals. Unfortunately, there were some diffculties accessing CAN system data to provide the output of the HVAC system. / Detta examensarbete beskriver arbetsprocess två i ett projekt som leds av trafikförvaltningen i Stockholm för att uppnå termiska komfort för passagerare i busstrafik.  Syftet med detta examensarbete är att utforma och implementera ett mätsystem bestående av åtta positioner i en buss. Varje position kan överföra data med hjälp av ett trådlöst kommunikationsprotokoll, en central enhet samlar in all data med hänsyn till mätningens noggrannhet och filtrering av felaktig data. För att uppnå detta utfördes en litteraturstudie för att undersöka mätningsmetoder för de olika parametrar. Olika kommunikationsprotokoll undersöktes för att bestämma en lämplig kommunikationsprotkoll för ett mätsystem som mäter klimat i bussar med passagerare ombord. Uteffekten av HVAC-systemet krävs också för att hjälpa trafikförvaltningen att bestämma fördelarna med att justera temperaturen i bussen för att nå den termiska komforten och hur den ledde till att spara energi. Systemet inkorporerar kommunikaitonsprotokollet ZigBee, ESP32-mikrokontroller i avsändarpositionerna och en Raspberry pi som fungerade som en central enhet för att samla in data och lagra det i ett filsystem med korrekta data som hjälper trafikförvaltningen att uppnå sina mål. Svårigheter uppstod med att få tillgång till CAN-system data för uteffekten av HVAC-systemet.

Zigbee network is a popular choice for deploying low power personal area network (LoWPAN). The application areas vary but the most popular are industrial area monitoring and home automation. But Zigbee has been identified to have weak security and is not applicable for industrial implementation. This paper is collaboration with Ericsson to investigate Zigbee network security and implementation. This paper will cover security solutions for Zigbee and touch on how to configure Zigbee network such that it can operate for a long period of time without battery changes. The security solutions will demonstrate how public-key respective symmetric key algorithm can be used for enhancing Zigbee security such that it provide authentication and authorization of joining devices while maintaining confidentiality and integrity of the network communication. Security solutions will also take regards to the power consumption of each proposed solution. For the network configuration part of the thesis, it will present node lifetime for different network configuration, i.e. how polling period between each message will affect the total cur- rent consumption of a node and how the joining procedure, depending on the security solution will affect the total node lifetime. Achieving longer node lifetime is desired because it is assumed that the network will be deployed in remote and unfavorable areas. The result of this paper compares different solutions for enhancing the security. Further, it concludes that Zigbee security with authentication and authorization of joining devices is reached through secret-splitting key establishment - which is the best solution. This is possible while maintaining low power consumption in the network. / Zigbee nätverk är ett populärt val vid uppsättning av ett nätverk med låg strömförbrukning. Zigbees användningsområde är olika men den är väldigt populär inom industriell områdesövervakning och hemautomation. Däremot har Zigbees säkerhet varit en nackdel, då det har framkommit att den inte möter kraven för industriell användning. Arbetet kom till genom ett samarbete med Ericsson och KTH för att undersöka Zigbee nätverks implementation och säkerhet. Arbetet bearbetar olika säkerhetslösningar för Zigbee nätverk och hur den kan implementeras för att uppnå långtidsanvändning utan batteribyte. Säkerhetslösningar bygger på public-key samt symmetric key kryptografi algoritmer för att förbättra och öka Zigbees säkerhet genom autentisering och tillåtelse av noder som ansluter sig till nätverket. Nätverkets konfiguration för långtidsanvändning redovisas genom att jämföra olika polling tidsintervaller mellan meddelanden. Långtidsanvändning utan batteribyte är viktigt för att nätverket kommer implementeras i ett avlägset område som är svåråtkomlig. Arbetet redovisar och jämföra olika lösningar för att öka säkerheten för Zigbee nätverk. Den optimala lösningen för att uppnå autentisering samt tillåtelse av noder som ansluter sig uppnås med nyckel skapande genom secret-splitting metoden. Metoden följer NIST rekommendationer och anses vara säker, därav uppfyller den kraven för industriell implementation. Nätverkets säkerhet ökar samt bibehåller ett nätverk med låg strömförbrukning.

Orientador: Marcelo Augusto Assunção Sanches / Resumo: O presente trabalho teve como objetivo o desenvolvimento de um dispositivo de estimulação vibro-tátil para reabilitação de pacientes com Doença de Parkinson (DP), que é uma doença progressiva e neurodegenerativa. A utilização de dispositivos que proporcionam estímulos externos, denominados pistas externas, podem melhorar os sintomas motores em pacientes com DP, principalmente os relacionados à marcha. Mesmo com evidências sobre a melhora na marcha, ainda não há um consenso sobre qual o melhor tipo de pista e, principalmente, a melhor configuração para a utilização, como posicionamento do dispositivo no paciente, frequência do estímulo, instante de ativação, dentre outros. Desta forma, neste trabalho foi desenvolvido um estimulador vibro-tátil com algumas flexibilidades, permitindo assim que o dispositivo não seja utilizado apenas no tratamento da DP, mas também em trabalhos de investigação sobre a forma mais eficaz de aplicação de pistas vibro-táteis. O dispositivo é composto por módulos independentes, um módulo de controle remoto e módulos de estimulação. Os módulos de estimulação podem ser fixados em diferentes partes do corpo e oferecem frequência variável. O dispositivo permite que o profissional da saúde tenha o controle do momento de aplicação e de retirada do estímulo, apenas utilizando um módulo de controle wireless. Os resultados obtidos evidenciaram que o acionamento do dispositivo pode ser realizado a uma distância de até 100 m, sem perder comunicação. A faixa de f... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of the present work was to develop a vibro-tactile stimulation device for the rehabilitation of patients with Parkinson's Disease (PD), which is a progressive and neurodegenerative disease. The use of devices that provide external clues, called external cueing, may improve motor symptoms in patients with PD, especially those related to gait. Even with evidence of improvement in gait, there is still no consensus as to the best type of cueing and specially the best configuration for use, such as device positioning in the patient, stimulus frequency, activation time, among others. Thus, in this work a vibro-tactile stimulator with some flexibilities was developed, allowing the device not to be used only in the treatment of PD, but also in research on the most effective way of applying vibro-tactile cueing. The device consists of independent modules, a remote control module and stimulation modules. These can be attached to different parts of the body and offer varying frequency. The device allows the health professional to have control of the moment of application and withdrawal of the stimulus, only using a wireless control module. The obtained results showed that the activation of the device can be carried out from a distance of up to 100m, without losing communication. The frequency range that can be used in this device is 170 Hz to 310 Hz. Initially there are two modules of stimulation, however it can be expanded to several modules, because the communication protocol ... (Complete abstract click electronic access below) / Mestre

Orientador: José Alfredo Covolan Ulson / Banca: Rogério Andrade Flauzino / Banca: Mario Eduardo Bordon / Resumo: O sistema de distribuiçã de energia elétrica no Brasil é constituído, na grande maioria, de alimentadores aéreos na classe 15 kV sujeitos a muitos tipos de defeitos. Embora existam muitos trabalhos propondo técnicas para a identificação e a localização das faltas, a maioria deles foi desenvolvida objetivando as redes de transmissão pouco ramificadas. Em se tratando de redes muito ramificadas e extensas, características princiapais de redes de distribuição elétrica, esses métodos não apresentam alta confiabilidade e segurança em termos de detecção, dificultando a localização das faltas. Este trabalho tem como objetivo descrever o desenvolvimento de um sistema de medição de baixo custo voltado para a monitoração de alimentadores aéreosm de distribuição de energia elétrica, que possibilite a identificação e a localização de faltas bem como a avaliação da qualidade da energia elétrica fornecida. Para tal, uma rede de sensores sem fio no padrão IEEE 802.15.4 é utilizada para adquirir os dados de tensão e corrente de cada frase e, a partir do processamento dessas informações, possibilitar a identificação de um ramal sob falta e a determinação do seu tipo. Com a instação de mediadores em pontos onde a rede de distribuição se ramifica, o ramal sob falta pode ser localizado, reduzindo assim o tempo de desligamento e os custos de manutenção / Abstract: The system of eletrecity distribution in Brazil is made mostly of air handlers in the class 15 kV, subject to many kinds of defects. Although there are many papers proposing techniques for the identification and location of faults, most of them were developed aiming at the broadcast networks little branched. In terms of networks very extensive and branched, like in distribution networks, these methods have low reliability and safety in terms of detection, makind the location of faults difficult. This paper aims to describe the development of a measurment system focused on low-cost monitoring of overhead distribution feeders of electricity, allowing for the identification and location of faults and the quality of power supplied. For this purpose, a network of wireless sensors on the IEEE 208.15.4 is used for data acquisition of each phase voltage and current and from the processing of such information is possible to determine a faulted extension and identification of its type. With the installation of meters at points where the distribution networks branches, the faulted extension can be located, thereby reducing the shutdown time and maintenance costs / Mestre

The surge of mobile devices, such as smartphones, and tables, demands additional capacity. On the other hand, Internet-of-Things (IoT) and smart grid, which connects numerous sensors, devices, and machines require ubiquitous connectivity and data security. Additionally, some use cases, such as automated manufacturing process, automated transportation, and smart grid, require latency as low as 1 ms, and reliability as high as 99.99\%. To enhance throughput and support massive connectivity, sharing of the unlicensed spectrum (3.5 GHz, 5GHz, and mmWave) is a potential solution. On the other hand, to address the latency, drastic changes in the network architecture is required. The fifth generation (5G) cellular networks will embrace the spectrum sharing and network architecture modifications to address the throughput enhancement, massive connectivity, and low latency. To utilize the unlicensed spectrum, we propose a fixed duty cycle based coexistence of LTE and WiFi, in which the duty cycle of LTE transmission can be adjusted based on the amount of data. In the second approach, a multi-arm bandit learning based coexistence of LTE and WiFi has been developed. The duty cycle of transmission and downlink power are adapted through the exploration and exploitation. This approach improves the aggregated capacity by 33\%, along with cell edge and energy efficiency enhancement. We also investigate the performance of LTE and ZigBee coexistence using smart grid as a scenario. In case of low latency, we summarize the existing works into three domains in the context of 5G networks: core, radio and caching networks. Along with this, fundamental constraints for achieving low latency are identified followed by a general overview of exemplary 5G networks. Besides that, a loop-free, low latency and local-decision based routing protocol is derived in the context of smart grid. This approach ensures low latency and reliable data communication for stationary devices. To address data security in wireless communication, we introduce a geo-location based data encryption, along with node authentication by k-nearest neighbor algorithm. In the second approach, node authentication by the support vector machine, along with public-private key management, is proposed. Both approaches ensure data security without increasing the packet overhead compared to the existing approaches.

<p>This thesis work started with an extensive literature study in several areas, ZigBee, instruments and measuring methods. The knowledge was implemented in use with the ZigBee modules from the two manufacturers ITN and Chipcon along with ZigBee Software Stack. Measuring methods were developed and software in ZigBee software Stack was developed to use in the ZigBee modules for the measurements. Developing measurement methods and performing measurements was an iterative process for the different measurements. The aim was to characterize the ZigBee modules in the most important areas during the extent of this master thesis work.</p>

This thesis work started with an extensive literature study in several areas, ZigBee, instruments and measuring methods. The knowledge was implemented in use with the ZigBee modules from the two manufacturers ITN and Chipcon along with ZigBee Software Stack. Measuring methods were developed and software in ZigBee software Stack was developed to use in the ZigBee modules for the measurements. Developing measurement methods and performing measurements was an iterative process for the different measurements. The aim was to characterize the ZigBee modules in the most important areas during the extent of this master thesis work.

With the development of powerful computational resources such as Digital Signal Processors and Field Programmable Gate Arrays, It has become possible to utilize many radio functions via software. This is the main concept of an up-and-coming technology of Software Defined Radio. In the Thesis, a number of platforms for implementation of Software Defined Radio has been evaluated. Platform that proved to be most suitable for the project was Ettus’ USRP N210. Using the platform, implementation of 802.15.4 Zigbee’s physical layer was done, where experiments whose outputs can later be used to compare performance with respect to "hardware radios" were performed. / Med utvecklingen av enheter med kraftfulla beräkningsegenskaper som “Digital Signal Processors” och “Field Programmable Gate Arrays” har det blivit möjligt att implementera flera radiofunktioner i mjukvara. Det är huvudkonceptet i den uppåtgående teknologin mjukvaru definierad radio.I det här examensarbetet har ett flertal plattformar för mjukvaru definierad radioutvärderats. Plattformen som visade sig vara mest lämplig för projektet var Ettus USRP N210. En implementation av IEEE 802.15.4 Zigbees fysiska lager har realiserats till plattformen. Experiment, vars utdata senare kan användas för att jämföra prestanda mellan mjukvaru definierad radio och hårdvaru baserad radio, har även utförts. / TESLA - Time-critical and Safe wireLess Automation communication / GAUSS - Guaranteed Automation communication Under Severe disturbanceS

Wireless Sensor Network (WSN) is an emerging multi-hop wireless network technology, and the greenhouse network monitoring system is one of the key applications of WSNs in which various parameters such as temperature, humidity, pressure and power can be monitored. Here, we aim to study the performance of a simulation-based greenhouse monitoring system. To design the greenhouse monitoring system based on WSN, we have used ZigBee-based devices (end devices, routers, coordinators, and actuators. Our proposed greenhouse monitoring network has been designed and simulated using the network simulator OPNET Modeller.The investigation is split into two; first, the aim is to find the optimal Transmit (Tx) power set out at sensor nodes and second, the focus is on studying how increasing the number of sensor nodes in the same greenhouse network will affect the overall network performance. ZigBee-based greenhouses corresponded to 4 network scenarios and are simulated using OPNET Modeller in which 22 different transmit (Tx) power (22 cases) in Scenario 1 is simulated, scenario 2, 3 and 4 estimated to 63, 126, 189 number of sensor nodes respectively. Investigating the performance of the greenhouse monitoring network performance metrics such as network load, throughput, packets sent/received and packets loss are considered to be evaluated under varied transmit (Tx) power and increasing number of sensor nodes. Out of the comprehensive studies concerning simulation results for 22 different transmit (Tx) power cases underlying the greenhouse monitoring network (Scenario1), it is found that packets sent/received and packets loss perform the best with the transmitted (Tx) power falling in a range of 0.9 mWatt to 1.0 mWatt while packet sent/received and packet loss are found to perform moderately with the transmitted (Tx) power values that lie in a range of 0.05 mWatt to 0.8 mWatt. Less than 0.05 mWatt and greater than 0.01 microWatt Tx power experience, the worst performance in terms of particularly packet dropped case. For instance, in the case of the packet dropped (not joined packet, i.e., generated at the application layer but not able to join the network due to lack of Tx power), with a Tx power of 0.01 mWatt, 384 packets dropped with a Tx power of 0.02 and 0.03 mWatt, 366 packets dropped, and with a Tx power of 0.04 and 0.05, 336 packet dropped.While increasing the number of sensor nodes, as in scenario 2, 3 and 4, dealing with sensor nodes 63, 126 and 189 correspondingly, the MAC load, MAC throughput, packet sent/received in scenario 2 are found to perform better than that of scenario 3 and scenario 4, while packet loss in scenarios 2, 3 and 4 appeared to be 15%, 12% and 83% correspondingly.