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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Scalable IoT Network Testbed with Hybrid Device Emulation

Zhao, Zhengan 19 August 2022 (has links)
In recent years, the Internet of Things (IoT) has been proliferating in various fields, such as health care, smart city, and connected autonomous vehicles. Accompanying the popularity of IoT are security attacks that exploit the vulnerabilities of many IoT devices. To build IoT anomaly detection systems, we need to collect and label a large amount data from diverse IoT scenarios, which is a time-consuming and prohibitive task if without the support of an IoT testbed. This thesis fills this urgent need by developing a scalable, flexible, safe, and secure IoT testbed. To make the testbed scalable, we need to reduce the hardware cost and make its architecture easily extendable. For this, we build a hybrid testbed consisting of real IoT devices, such as motion sensors and smart cameras, and emulated devices with Raspberry Pi. The emulated devices can replace real IoT devices with the same operational behaviour as real IoT devices but at a much lower price. Flexibility means the testbed can easily simulate different application scenarios. To make the testbed flexible, we build a dedicated data management module to facilitate the complex tasks in generating diverse traffic patterns, reproducing security attacks, collecting, visualizing, and analyzing network traffic. Testbed safety means the testbed will not cause any adverse impact to the Internet, and testbed security means protecting it from outside attacks. For safety, we carefully analyze the source code and the behaviour of launched attacks and configure a traffic filter to strictly contain the attack traffic within the testbed. For security, we scan and analyze the security of all IoT devices within the testbed to ensure no exposed vulnerability in the used devices. / Graduate
2

On Cyber-Physical Security of Smart Grid: Data Integrity Attacks and Experiment Platform

Tan, Song 07 May 2016 (has links)
A Smart Grid is a digitally enabled electric power grid that integrates the computation and communication technologies from cyber world with the sensors and actuators from physical world. Due to the system complexity, typically the high cohesion of communication and power system, the Smart Grid innovation introduces new and fundamentally different security vulnerabilities and risks. In this work, two important research aspects about cyber-physical security of Smart Grid are addressed: (i) The construction, impact and countermeasure of data integrity attacks; and (ii) The design and implementation of general cyber-physical security experiment platform. For data integrity attacks: based on the system model of state estimation process in Smart Grid, firstly, a data integrity attack model is formulated, such that the attackers can generate financial benefits from the real-time electrical market operations. Then, to reduce the required knowledge about the targeted power system when launching attacks, an online attack approach is proposed, such that the attacker is able to construct the desired attacks without the network information of power system. Furthermore, a network information attacking strategy is proposed, in which the most vulnerable meters can be directly identified and the desired measurement perturbations can be achieved by strategically manipulating the network information. Besides the attacking strategies, corresponding countermeasures based on the sparsity of attack vectors and robust state estimator are provided respectively. For the experiment platform: ScorePlus, a software-hardware hybrid and federated experiment environment for Smart Grid is presented. ScorePlus incorporates both software emulator and hardware testbed, such that they all follow the same architecture, and the same Smart Grid application program can be tested on either of them without any modification; ScorePlus provides a federated environment such that multiple software emulators and hardware testbeds at different locations are able to connect and form a unified Smart Grid system; ScorePlus software is encapsulated as a resource plugin in OpenStack cloud computing platform, such that it supports massive deployments with large scale test cases in cloud infrastructure.
3

Monitoring use cases in the FIBRE-BR testbed

Dourado, Raphael Augusto de Sousa 24 July 2014 (has links)
Many researchers believe that the Internet is “ossified”, that is, its design is preventing the network to evolve in aspects such as security, mobility, and content distribution. However, it is difficult to test new ideas in a production environment like the Internet due to its stability requirements. As an alternative, part of the network research community is focused on building large-scale infrastructures called testbeds, where they can build their “own” network and test their ideas in a more realistic environment, similar to the Internet itself. This work discusses the challenges of a key function in a testbed: monitoring. To do this, we reviewed the state-of-the-art in monitoring systems for testbeds and then identified, described, and implemented a set of monitoring use cases in the FIBRE testbed. By implementing these use cases, we validate our proposals and lay a framework reusable in other similar environments. / Submitted by Luiz Felipe Barbosa (luiz.fbabreu2@ufpe.br) on 2015-03-10T17:26:38Z No. of bitstreams: 2 DISSERTAÇÃO Raphael Augusto de Sousa Dourado.pdf: 6341527 bytes, checksum: c6ee052e4d2ce1085459d2bca175af0e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-11T17:36:24Z (GMT). No. of bitstreams: 2 DISSERTAÇÃO Raphael Augusto de Sousa Dourado.pdf: 6341527 bytes, checksum: c6ee052e4d2ce1085459d2bca175af0e (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2014-07-24 / Muitos pesquisadores acreditam que a Internet está “ossificada”, ou seja, sua própria estrutura a impede de evoluir em aspectos como segurança, mobilidade e distribuição de conteúdo. No entanto, há uma dificuldade em testar novas ideias em ambiente de produção como a Internet devido aos requisitos de estabilidade dos mesmos. Este impasse levou parte da comunidade de pesquisa em Redes de Computadores a construir infraestruturas em larga escala chamadas testbeds, onde pesquisadores podem montar sua “própria” rede privada e então testar suas ideias em um ambiente similar à Internet. Este trabalho discute os desafios de uma das principais tarefas de um testbed: monitoração. Para tal, foi realizado um levantamento do estado da arte em sistemas de monitoração para testbeds e, a partir deste estudo, foi identificado, descrito e implementado um conjunto de casos de uso de monitoração no contexto do testbed FIBRE. A implementação destes casos de uso validou as propostas deste trabalho, as quais podem também ser aplicadas a outros ambientes similares.
4

Microcontroller Based Multiple-Input Multiple-Output Transmitter

Kanday, Balaji Madapuci 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper describes how a microcontroller based system can be used to generate the signals needed in a multiple-input multiple-output (MIMO) system transmitter. The limited computational speed of the microcontroller, along with other tasks which the controller may need to handle, places limits on the throughput of the system, and the complexity of the MIMO signal design. However this can be a low cost design, and the microcontroller can be used to perform other operations in the system, which may make it attractive in some applications.
5

Experimental Challenges in Wireless Sensor Networks — Environment, Mobility, and Interference

Rensfelt, Olof January 2012 (has links)
Wireless sensor networks are used to collect sensor data in different applications such as environmental monitoring, smart building control, and health care applications. Wireless sensor nodes used are typically small, low-cost, and battery powered. The nodes are often hard to access after deployment, for example when they are in remote  locations. Another property of wireless sensor networks is that their operation is dependent on the environment they operate in, both due to the specific sensor readings but also due to the effects on communication by factors such as fading and radio interference. This makes it important to evaluate a wireless sensor network in its intendent target environment before final deployment. To enable experiments with wireless sensor networks in their target environment, we have designed and implemented a testbed called Sensei-UU. It is designed to allow WSN experiments to be repeated in different locations, thus exposing effects caused by the environment. To allow this, the testbed is designed to be easily moved between experimental sites. One type of WSN applications Sensei-UU is aimed to evaluate is protocols where nodes are mobile. Mobile testbed nodes are low-cost robots which follow a tape track on the floor. The localization accuracy of the robot approach is evaluated and is accurate enough to expose a protocol to fading phenoma in a repeatable manner. Sensei-UU has helped us develop a lightweight interference classification approach, SoNIC, which runs on standard motes. The approach only use information from a standard cc2420 chipset available when packets are received. We believe that the classification accuracy is good enough to motivate specific transmission techniques avoiding interference. / WISENET
6

An open virtual testbed for industrial control system security research

Reaves, Bradley Galloway 06 August 2011 (has links)
ICS security has been a topic of scrutiny and research for several years, and many security issues are well known. However, research efforts are impeded by a lack of an open virtual industrial control system testbed for security research. This thesis describes a virtual testbed framework using Python to create discrete testbed components (including virtual devices and process simulators). This testbed is designed such that the testbeds are interoperable with real ICS devices and that the virtual testbeds can provide comparable ICS network behavior to a laboratory testbed. Two testbeds based on laboratory testbeds have been developed and have been shown to be interoperable with real industrial control systemequipment and vulnerable to attacks in the samemanner as a real system. Additionally, these testbeds have been quantitatively shown to produce traffic close to laboratory systems (within 90% similarity on most metrics).
7

Development and Applications of the Modular Automotive Technology Testbed (MATT) to Evaluate Hybrid Electric Powertrain Components and Energy Management Strategies

Lohse-Busch, Henning 16 October 2009 (has links)
This work describes the design, development and research applications of a Modular Automotive Technology Testbed (MATT). MATT is built to evaluate technology components in a hybrid vehicle system environment. MATT can also be utilized to evaluate energy management and torque split control strategies and to produce physical measured component losses and emissions to monitor emissions behavior. In the automotive world, new technology components are first developed on a test bench and then they are integrated into a prototype vehicle for transient evaluation from the vehicle system perspective. This process is expensive and the prototype vehicles are typically inflexible in hardware and software configuration. MATT provides flexibility in component testing through its component module approach. The flexible combination of modules provides a vehicle environment to test and evaluate new technology components. MATT also has an open control system where any energy management and torque split strategy can be implemented. Therefore, the control's impact on energy consumption and emissions can be measured. MATT can also emulate different types and sizes of vehicles. MATT is a novel, unique, flexible and powerful automotive research tool that provides hardware-based data for specific research topics. Currently, several powertrain modules are available for use on MATT: a gasoline engine module, a hydrogen engine module, a virtual scalable energy storage and virtual scalable motor module, a manual transmission module and an automatic transmission module. The virtual battery and motor module uses some component Hardware-In-the-Loop (HIL) principles by utilizing a physical motor powered from the electric grid in conjunction with a real time simulation of a battery and a motor model. This module enables MATT to emulate a wide variety of vehicles, ranging from a conventional vehicle to a full performance electric vehicle with a battery pack that has virtually unlimited capacity. A select set of PHEV research studies are described in this dissertation. One of these studies had an outcome that influenced the PHEV standard test protocol development by SAE. Another study investigated the impact of the control strategy on emissions of PHEVs. Emissions mitigation routines were integrated in the control strategies, reducing the measured emissions to SULEV limits on a full charge test. A special component evaluation study featured in this dissertation is the transient performance characterization of a supercharged hydrogen internal combustion engine on MATT. Four constant air-fuel ratio combustions are evaluated in a conventional vehicle operation on standard drive cycles. Then, a variable air fuel ratio combustion strategy is developed and the test results show a significant fuel economy gain compared to other combustion strategies, while NOx emissions levels are kept low. / Ph. D.
8

Assessment of Cyber Vulnerabilities and Countermeasures for GPS-Time Synchronized Measurements in Smart Grids

Khan, Imtiaj 02 July 2024 (has links)
We aim at expanding the horizon of existing research on cyberattacks against the time-syncrhonized devices such as PMUs and PDCs, along with corresponding countermeasures. We develop a PMU-PDC cybersecurity testbed at Virginia Tech Power and Energy Center (PEC) lab. The testbed is able to simulate real-world GPS-spoofing attack (GSA) and false data injection attack (FDIA) scenarios. Moreover, the testbed can incorporates cyberattack detection algorithm in pseudo real-time. After that, we propose three stealthy attack scenarios that exploit the vulnerabilities of time-synchronization for both PMU and PDC. The next part of this dissertation is the enhancement of Hankel-matrix based bad data detection model. The existing general Hankel-matrix based bad data detection model provide satisfactory performance. However, it fails in differentiating GPS-spoofing attack from FDIA. We propose an enhanced phase angle Hankel-matrix model that can conclusively identify GPS-spoofing attack. Furthermore, we reduce the computational burden for Hankel-matrix based bad data and cyberattack detection models. Finally, we verify the effectiveness of our enhanced Hankel-matrix model for proposed stealthy attack scenarios. / Doctor of Philosophy / Modern power systems incorporate numerous smart metering devices and communication channels to provide better resiliency against hazardous situations. One such metering device is Phasor Measurement Device (PMU), what provides GPS time-synchronized measurements to the system operator. The time-synchronized measurements are critical in ensuring the cyber and physical security of grids. However, like other smart devices, PMUs are susceptible to conventional cyberattacks. In addition to conventional cyberattacks, PMUs are also vulnerable to attacks against its time-synchronization. In this work, we dig deep into the realm of cyberattacks against time-synchronization of PMUs. We propose novel stealthy attacks against PMU time synchronization. Furthermore, we enhance existing attack detection model to conclusively identify such stealthy attacks and implemented the model in cybersecurity testbed that we developed at Virginia Tech.
9

Estratégias de beaconing para comunicação em redes veiculares / Beaconing strategies for communication in vehicular networks

Yokoyama, Roberto Sadao 11 July 2014 (has links)
Em sistemas de transporte inteligentes, as redes veiculares têm um papel fundamental. Por meio da comunicação sem fio, veículos irão disseminar conteúdo nessas redes para melhorar a segurança e eficiência no transporte, prover aplicações de entretenimento etc. Beaconing, proposto originalmente para aplicações de segurança, é usado neste estudo como uma das maneiras de disseminação de conteúdo, onde o nó emissor insere uma informação em um quadro de beacon, que é propagado em broadcast. A maioria dos estudos da literatura focam na otimização de desempenho de beaconing e utilizam o método de simulação para validação e avaliação. Esta tese explora estratégias de beaconing com validação e avaliação usando método experimental em ambientes reais para resolver problemas relacionados a aplicações cooperativas de localização e posicionamento de veículos. Para tanto, foi implantado um testbed veicular para realização de testes tradicionais, como o de desempenho sobre os parâmetros de comunicação, mas principalmente de novos protocolos que transmitem informações adicionais nos beacons. Os principais resultados são: i) uma aplicação para inferência da distância entre os veículos por meio do sinal recebido de rádio frequência, ii) localização de pontos de interesse para motoristas e passageiros e por fim, iii) verificação da localização do veículo e disseminação de beacons anonimamente. Desta maneira, este estudo demonstrou, por meio de experimentos em ambientes reais, que estratégias de beacons podem ser aplicadas com sucesso para aplicações que usam cooperação para localização e posicionamento em redes veiculares / Vehicular networks play an important role in intelligent transportation systems. Through wireless communication, vehicles can disseminate information to improve transportation safety and efficiency, and provide entertainment applications. Beaconing, first proposed for safety applications, is used in this study as one of the ways to disseminate information, in which the source node adds information to the beacon frame, which is finally propagated in broadcast. Most studies in the literature focus on beaconing performance and optimization using simulations. This thesis explores beaconing strategies, applying experimental methods to validate and evaluate beaconing in real environments, solving problems related to cooperative location applications and vehicles positioning. A vehicular network testbed was developed to perform traditional tests, such as the performance of the communication parameters and to specifically test novel protocols that transmit additional information in the beacons. The key contributions are: i) an application to infer the distance between vehicles via the radio frequency signal received; ii) location of points of interest for drivers and passengers; and iii) location verification of vehicle and anonymous beacon broadcast. In brief, this study demonstrated, through experiments in real environments, that beacon strategies can be successfully applied to problems of location and positioning in vehicular networks
10

Estratégias de beaconing para comunicação em redes veiculares / Beaconing strategies for communication in vehicular networks

Roberto Sadao Yokoyama 11 July 2014 (has links)
Em sistemas de transporte inteligentes, as redes veiculares têm um papel fundamental. Por meio da comunicação sem fio, veículos irão disseminar conteúdo nessas redes para melhorar a segurança e eficiência no transporte, prover aplicações de entretenimento etc. Beaconing, proposto originalmente para aplicações de segurança, é usado neste estudo como uma das maneiras de disseminação de conteúdo, onde o nó emissor insere uma informação em um quadro de beacon, que é propagado em broadcast. A maioria dos estudos da literatura focam na otimização de desempenho de beaconing e utilizam o método de simulação para validação e avaliação. Esta tese explora estratégias de beaconing com validação e avaliação usando método experimental em ambientes reais para resolver problemas relacionados a aplicações cooperativas de localização e posicionamento de veículos. Para tanto, foi implantado um testbed veicular para realização de testes tradicionais, como o de desempenho sobre os parâmetros de comunicação, mas principalmente de novos protocolos que transmitem informações adicionais nos beacons. Os principais resultados são: i) uma aplicação para inferência da distância entre os veículos por meio do sinal recebido de rádio frequência, ii) localização de pontos de interesse para motoristas e passageiros e por fim, iii) verificação da localização do veículo e disseminação de beacons anonimamente. Desta maneira, este estudo demonstrou, por meio de experimentos em ambientes reais, que estratégias de beacons podem ser aplicadas com sucesso para aplicações que usam cooperação para localização e posicionamento em redes veiculares / Vehicular networks play an important role in intelligent transportation systems. Through wireless communication, vehicles can disseminate information to improve transportation safety and efficiency, and provide entertainment applications. Beaconing, first proposed for safety applications, is used in this study as one of the ways to disseminate information, in which the source node adds information to the beacon frame, which is finally propagated in broadcast. Most studies in the literature focus on beaconing performance and optimization using simulations. This thesis explores beaconing strategies, applying experimental methods to validate and evaluate beaconing in real environments, solving problems related to cooperative location applications and vehicles positioning. A vehicular network testbed was developed to perform traditional tests, such as the performance of the communication parameters and to specifically test novel protocols that transmit additional information in the beacons. The key contributions are: i) an application to infer the distance between vehicles via the radio frequency signal received; ii) location of points of interest for drivers and passengers; and iii) location verification of vehicle and anonymous beacon broadcast. In brief, this study demonstrated, through experiments in real environments, that beacon strategies can be successfully applied to problems of location and positioning in vehicular networks

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