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Desenvolvimento de uma rede de sensores sem fio para processamento de sinais acústicos marinhos. / Development of a wireless sensor network for marine acoustic signals processing.Durante, Gabriel 21 September 2018 (has links)
O crescente interesse pela caracterização de parâmetros acústicos marinhos esbarra nos poucos dispositivos eletrônicos que permitem capturar, armazenar, processar e difundir dados. Os equipamentos atuais que possibilitam obter dados referentes à vida marinha e permitem estudar as influências humanas sobre ela possuem alto custo e funcionam de forma isolada, ou seja, normalmente não há comunicação com outros dispositivos, o que dificulta a monitorização de eventos em tempo real. Sendo assim, neste trabalho são revisadas as características necessárias para estabelecer uma rede de sensores sem fio (RSSF) de alta confiabilidade, utilizando-se o conceito de Internet das Coisas (IoT). São comparados os protocolos MQTT-SN e CoAP com ferramentas de simulação e implementada uma rede de sensoriamento acústico aquático constituída de três nós sensores autônomos e um gateway usando o protocolo 6LowPAN. Também é implementada a tradução para o protocolo IPV4 no gateway, de modo que o funcionamento da rede de sensores pode ser monitorada num servidor remoto na Internet em tempo real. O desempenho da rede é avaliado com relação à autonomia energética, capacidade de memória, alcance e confiabilidade na entrega dos dados. As unidades autônomas desenvolvidas podem operar ininterruptamente, com uso de baterias, por aproximadamente 125 horas com memória de gravação de 48GB e alcance de 100m aproximadamente. Por fim, é implementado o pré-processamento dos dados sonoros visando a detecção de eventos acústicos aquáticos. / The increasing interest in the characterization of marine acoustic parameters needs electronic devices that allow capture, store, process, and diffuse data. Current equipment that provides data about the marine life and allow the study of human influences on it have high cost and work isolated, that is, without communication with other devices, which makes it difficult to monitor events in real time. Therefore, this work revises the necessary features to establish a high reliability wireless sensor network (WSN) by applying the concept of Internet of Things (IoT). The protocols MQTT-SN and CoAP are compared with simulation tools and a network is implemented to sense acoustic signals, composed by three autonomous sensor nodes and a gateway using the protocol 6LowPAN. The translation for the IPV4 protocol in the gateway is also implemented, so the operation of the sensor network can be monitored by a remote server on the Internet in real time. The performance of the network is evaluated in relation to power autonomy, memory capacity, reach and reliability. The autonomous sensor nodes can operate uninterrupted, with use of batteries, for approximately 125 hours with 48GB storage for recording and approximately 100m range. Finally, data pre-processing is implemented in order to detect aquatic acoustic events.
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Desenvolvimento de uma rede de sensores sem fio para processamento de sinais acústicos marinhos. / Development of a wireless sensor network for marine acoustic signals processing.Gabriel Durante 21 September 2018 (has links)
O crescente interesse pela caracterização de parâmetros acústicos marinhos esbarra nos poucos dispositivos eletrônicos que permitem capturar, armazenar, processar e difundir dados. Os equipamentos atuais que possibilitam obter dados referentes à vida marinha e permitem estudar as influências humanas sobre ela possuem alto custo e funcionam de forma isolada, ou seja, normalmente não há comunicação com outros dispositivos, o que dificulta a monitorização de eventos em tempo real. Sendo assim, neste trabalho são revisadas as características necessárias para estabelecer uma rede de sensores sem fio (RSSF) de alta confiabilidade, utilizando-se o conceito de Internet das Coisas (IoT). São comparados os protocolos MQTT-SN e CoAP com ferramentas de simulação e implementada uma rede de sensoriamento acústico aquático constituída de três nós sensores autônomos e um gateway usando o protocolo 6LowPAN. Também é implementada a tradução para o protocolo IPV4 no gateway, de modo que o funcionamento da rede de sensores pode ser monitorada num servidor remoto na Internet em tempo real. O desempenho da rede é avaliado com relação à autonomia energética, capacidade de memória, alcance e confiabilidade na entrega dos dados. As unidades autônomas desenvolvidas podem operar ininterruptamente, com uso de baterias, por aproximadamente 125 horas com memória de gravação de 48GB e alcance de 100m aproximadamente. Por fim, é implementado o pré-processamento dos dados sonoros visando a detecção de eventos acústicos aquáticos. / The increasing interest in the characterization of marine acoustic parameters needs electronic devices that allow capture, store, process, and diffuse data. Current equipment that provides data about the marine life and allow the study of human influences on it have high cost and work isolated, that is, without communication with other devices, which makes it difficult to monitor events in real time. Therefore, this work revises the necessary features to establish a high reliability wireless sensor network (WSN) by applying the concept of Internet of Things (IoT). The protocols MQTT-SN and CoAP are compared with simulation tools and a network is implemented to sense acoustic signals, composed by three autonomous sensor nodes and a gateway using the protocol 6LowPAN. The translation for the IPV4 protocol in the gateway is also implemented, so the operation of the sensor network can be monitored by a remote server on the Internet in real time. The performance of the network is evaluated in relation to power autonomy, memory capacity, reach and reliability. The autonomous sensor nodes can operate uninterrupted, with use of batteries, for approximately 125 hours with 48GB storage for recording and approximately 100m range. Finally, data pre-processing is implemented in order to detect aquatic acoustic events.
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Lightweight Security Solutions for the Internet of ThingsRaza, Shahid January 2013 (has links)
The future Internet will be an IPv6 network interconnecting traditional computers and a large number of smart object or networks such as Wireless Sensor Networks (WSNs). This Internet of Things (IoT) will be the foundation of many services and our daily life will depend on its availability and reliable operations. Therefore, among many other issues, the challenge of implementing secure communication in the IoT must be addressed. The traditional Internet has established and tested ways of securing networks. The IoT is a hybrid network of the Internet and resource-constrained networks, and it is therefore reasonable to explore the options of using security mechanisms standardized for the Internet in the IoT. The IoT requires multi-facet security solutions where the communication is secured with confidentiality, integrity, and authentication services; the network is protected against intrusions and disruptions; and the data inside a sensor node is stored in an encrypted form. Using standardized mechanisms, communication in the IoT can be secured at different layers: at the link layer with IEEE 802.15.4 security, at the network layer with IP security (IPsec), and at the transport layer with Datagram Transport Layer Security (DTLS). Even when the IoT is secured with encryption and authentication, sensor nodes are exposed to wireless attacks both from inside the WSN and from the Internet. Hence an Intrusion Detection System (IDS) and firewalls are needed. Since the nodes inside WSNs can be captured and cloned, protection of stored data is also important. This thesis has three main contributions. (i) It enables secure communication in the IoT using lightweight compressed yet standard compliant IPsec, DTLS, and IEEE 802.15.4 link layer security; and it discusses the pros and cons of each of these solutions. The proposed security solutions are implemented and evaluated in an IoT setup on real hardware. (ii) This thesis also presents the design, implementation, and evaluation of a novel IDS for the IoT. (iii) Last but not least, it also provides mechanisms to protect data inside constrained nodes. The experimental evaluation of the different solutions shows that the resource-constrained devices in the IoT can be secured with IPsec, DTLS, and 802.15.4 security; can be efficiently protected against intrusions; and the proposed combined secure storage and communication mechanisms can significantly reduce the security-related operations and energy consumption.
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Securing Communication in IP-Connected Industrial Wireless Sensor NetworksRaza, Shahid January 2011 (has links)
With the advent of wireless sensor networks (WSN) and success of wirelesscommunication in the local and personal area networks such asWi-Fi and Bluetoothmore serious efforts to apply standard wireless communication in sensitiveindustrial networks were initiated. This effort resulted in the standardizationof WirelessHART. Other standardization efforts include ISA 100.11a andZigBee. Keeping in mind the nature of wireless communication and sensitivityof industrial environments security of these network gets greater importance. In this thesis we work on security issues in industrial WSN in general andIP-connected WSN in particular. Currently WirelessHART is the only approvedstandard for secure wireless communication in industrial WSNs. Westart our work with the analysis of security mechanisms in WirelessHART.We propose solutions for the security shortcomings in WirelessHART, and designand implement the missing security components. Particularly, we specify,design, implement, and evaluate the first open security manager for WirelessHARTnetworks. With the standardization of IP in WSNs (6LoWPAN) and birth of Internetof Things the need for IP communication in industrial WSN is getting importance.The recently proposed ISA 100.11a standard is IP-based since its inception.Also standardization efforts are in progress to apply IP in WirelessHARTand Zigbee. Recently, WSNs and traditional IP networks are more tightly integratedusing IPv6 and 6LoWPAN. We realize the importance of having aninteroperable standardized secure IP communication in industrial WSNs. IPSecurity (IPsec) is a mandatory security solution in IPv6. We propose to useIPsec for 6LoWPAN enabled industrial WSNs. However, it is not meaningfulto use IPsec in its current form in resource constrained WSNs. In additionto providing security solutions for WirelessHART, in this thesis we also specify,design, implement, and extensively evaluate lightweight IPsec that enablesend-to-end secure communication between a node in a 6LoWPAN and a device in the traditional Internet. Our results show that lightweight IPsec is a sensibleand practical solution for securing WSN.
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Multichannel Communication in Contiki's Low-power IPv6 StackAl Nahas, Beshr January 2013 (has links)
Vast majority of wireless appliances used in household, industry and medical field share the ISM frequency band. These devices need to coexist and thus are challenged to tolerate their mutual interference. One way of dealing with this is by using frequency hopping; where the device changes its radio channel periodically. Consequently, communications will not suffer from the same interference each time; instead, it should be fairer and more stable. This thesis investigates the aforementioned problem in the field of low power wireless sensor networks and Internet of Things where Contiki OS is used. We introduce a low-power pseudo-random frequency-hopping MAC protocol which is specifically characterized as a duty cycled asynchronous sender-initiated LPL style protocol. We illustrate two flavors of the protocol; one that does not use any dedicated channel and another which allows dedicated broadcast channels that can implement frequency-hopping as well. We implement the protocol in C for real hardware and extensively test and evaluate it in a simulated environment which runs Contiki. It proved to work with Contiki's IPv6 stack running RPL (the standardized routing protocol for low power and lossy wireless networks). We compare the performance of the implemented protocol to the singlechannel ContikiMAC with varying levels of interference. Results show a reduction down to 56% less radio-on time (1.50% vs. 3.4%) and 85% less latency (306 ms vs. 2050 ms) in the presence of noise, while keeping a good basecost in noise-free environments with 1.29% radio duty cycle when using 9 channels with no dedicated broadcast channels (vs. 0.80% for single channel) and 252 ms average latency(vs. 235 ms). Moreover, the results show that the multichannel protocol performance metrics converge to almost the same values regardless of the noise level. Therefore, it is recommended as a good alternative to single channel ContikiMAC in realworld deployments where noise presence is anticipated.
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Protokol IPv6 v bezdrátových senzorových sítích / IPv6 for Wireless Sensor NetworksPolak, Martin January 2011 (has links)
This thesis deals with the issues 6LoWPAN protokolu and implementation of IPv6 on the specied platform. Introduction thesis deals with the explanation of wireless sensor networks. Next it was descibed 6LoWPAN protocol, which maps IPv6 on standard IEEE 802.15.4. The thesis further concentrates to exploration of possible operation systems, that are designed for sensor networks and then followed by comparison of their characteristics and advantages. The fth chapter is focused on he implementation of the operating system to the sensor node Iris, introduction Iris and with the structure of the operating system Contiki OS. At the end of thesis is description of the implementation of this system in the sensor node Iris.
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Sběr dat z webových serverů v prostředí bezdrátové senzorové sítě / Web-based data collection in Wireless Sensor NetworksVelký, Petr January 2011 (has links)
This thesis deals with the feasibility collecting data from web servers running on the nodes in sensor networks. It focuses on sensor network based on IEEE 802.15.4 and 6LoWPAN. The work itself is divided to the node side and server side.REST web services on the node‘s Web server provides sensor data. These data are collected with Java application running on the sensor network server. This servers stores collected data in a database.
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Vizualizace polohy senzorových jednotek / Location visualization of sensor unitsHulanský, Jozef January 2014 (has links)
This master thesis deals with wireless sensor network with protocol IPv6. In the begining there are explained the priciples of communication in wireless sensor network, and based on this teories are configured a wireles network with predefined development kit. Furthermore, by using geographic coordinates, positions of the nodes are displayed on a website, what is a part of this thesis. On this website are also presented the measured values from sensors. For saving all informations and measured values about each nodes was used remote MySQL server. Communication between this server and 6LoWPAN network provide Perl script which is runs at periodical intervals. With this method automatization of the whole system are ensured.
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A Proxy for Distributed Hash Table based Machine-to-Machine NetworksLi, Daoyuan January 2011 (has links)
Wireless sensor networks (WSNs) have been an increasingly interest for both researchers and entrepreneurs. As WSN technologies gradually matured and more and more use is reported, we find that most of current WSNs are still designed only for specific purposes. For example, one WSN may be used to gather information from a field and the collected data is not shared with other parties. We propose a distributed hash table (DHT) based machine-to-machine (M2M) system for connecting different WSNs together in order to fully utilize information collected from currently available WSNs. This thesis specifically looks at how to design and implement a proxy for such a system. We discuss why such a proxy can be useful for DHT-based M2M systems, what the proxy should consist of, and what kind of architecture is suitable. We also look into different communication protocols that can be used in these systems and discuss which ones best suit our purposes. The design of the proxy focuses on network management and service discovery of WSNs, and security considerations as well as caching mechanisms in order to improve performance. A prototype is implemented based on our design and evaluated. We find it feasible to implement such a DHT-based M2M system and a proxy in the system can be necessary and useful. Finally, we draw conclusions and discuss what future work remains to be done.
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Operating systems for resource constraint Internet of Things devices: An evaluationElvstam, Andreas, Nordahl, Daniel January 2016 (has links)
Internet of Things (IoT) är ett område under omfattande utveckling, både vad det gäller hårdvara och mjukvara. När det gäller hårdvaruplattformar för IoT enheter finns det platt-formar som är kraftfulla nog att exekvera ett reguljärt OS som t.ex. Linux. Andra hårdvaru-plattformar är inte tillräckligt kraftfulla för att exekvera reguljära OS och för dessa plattformar finns ett behov av resurseffektiva små IoT OS. Dessa resurssnåla OS behöver kunna hantera många av de funktioner som reguljära OS erbjuder, men på ett betydligt mer effektivt sätt.Det har under de senaste åren släppts en uppsjö av olika IoT OS för resurssnåla enheter och därför är syftet med denna rapport en utvärdering av IoT OS för strömsnåla resurssvaga IoT enheter. Utvärdering genomförs på IoT OS:en Contiki, mbed, RIOT och Zephyr. Målet med utvärderingen är att fastställa viktiga egenskaper för ett IoT OS för strömsnåla resurssvaga IoT enheter, och att belysa svårigheter och erfarenheter relaterade till konstruktionsprocessen av en prototyp för IoT enheter. Utvärderingen genomfördes genom att samla in fyra olika typer av data relaterade till IoT OS:en, och sedan utvärdera denna data med hjälp av en kriteriebaserad utvärderingsmetod.Utvärderingen resulterade i en lista av sex viktiga egenskaper för små resurs snåla IoT operativsystem. Dess resultat belyser även svårigheter och erfarenheter som framkommit under byggprocessen av prototyperna baserade på IoT OS:en.Slutsatsen av denna rapport bidrar med erfarenheter från byggning av prototyper IoT OS för resurssnåla enheter, samt ett utvärderingsresultat för IoT OS:en med hänsyn till de sex viktiga IoT OS egenskaperna. / The Internet of Things (IoT) is a large and rapidly expanding area with regards to both hardware platforms and software. When it comes to hardware platforms for the IoT some are more powerful and able to run a traditional OS like Linux, while other platforms are too constraint to do so. To ease the development within the IoT area an appropriate IoT OS is needed for these constrained hardware platforms, which can handle most of the functionality a traditional OS offer.Therefore, we evaluate IoT OSs targeted for low performance battery powered devices. In this thesis Contiki, mbed, RIOT and Zephyr are evaluated. The aim of this evaluation is to determine important IoT OS characteristics for resource constrained devices, and to highlight difficulties and experiences related to the building process of prototypes for such IoT devices.The evaluation of the IoT OSs were conducted on four types of data with regards to several measurable OS characteristics according to a criteria based evaluation method.The evaluation resulted in a list of six IoT OS characteristics important for wireless, resource constrained and battery powered devices. Furthermore the evaluation highlights potential setbacks during the building process of a prototype system for such devices and it also explains what experiences that can be gained.The conclusion of this thesis contributes with experience related to IoT OS prototype construction and also an evaluation result with respect to the six IoT OS characteristics for constraint battery driven devices.
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