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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.
191

Experimental Comparison of Radio Duty Cycling Protocols for Wireless Sensor Networks

Uwase, Marie-Paule 30 October 2018 (has links) (PDF)
Wireless sensor networks are often battery powered and therefore their power consumption is of critical importance. Power requirements can be reduced by switching off radios when they are not needed and by using multi-hop communications to reduce the length of the radio links. Multi-hop communications however require message routing through the network. The Routing Protocol for lossy networks (RPL) has been designed by the Internet Engineering Task Force (IETF) for seamless integration of wireless sensor networks in the Internet. For switching on and off radios, radio duty cycling (RDC) protocols have been added to the traditional medium access control (MAC) protocols. Despite the fact they belong to different layers in the communications stack, it is intuitively clear that the choice of a specific RDC protocol for saving energy can influence the performances of RPL. Exploring experimentally this influence was the initial goal of this research. A 25 nodes wireless sensor network using Zolertia Z1 motes and the Contiki software was used for this investigation. Performance measurements without RDC protocol and with the three different RDC protocols readily available in Contiki were organized and the results of the experiments were compared. Unfortunately, with all three RDC protocols, serious malfunctions obscured the experimental results. Those malfunctions did not show up in absence of a RDC protocol and they could not be reproduced by our simulation studies. To tackle this issue, the behavior of the RDC protocols was scrutinized by means of experimental set-ups that eliminated as much as possible all non RDC related issues. Many, quite varied, malfunctions were discovered which all could have caused the observed RPL issues. Further research and better experimental set-ups made clear that all the discovered RDC malfunctions could be attributed to two real-world facts that were not considered by the implementers of the Contiki RDC protocols. The first cause is the small frequency difference between hardware real time clocks in stand-alone motes. The second is that the threshold built in the receiver to detect radio activity is much higher than the minimum level of signal that the same receiver can decode. Work-arounds have been designed for the observed malfunctions and they have been tested by means of a systematic comparison of the performance of the three modified RDC protocols. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished
192

An Approach to QoS-based Task Distribution in Edge Computing Networks for IoT Applications

January 2018 (has links)
abstract: Internet of Things (IoT) is emerging as part of the infrastructures for advancing a large variety of applications involving connections of many intelligent devices, leading to smart communities. Due to the severe limitation of the computing resources of IoT devices, it is common to offload tasks of various applications requiring substantial computing resources to computing systems with sufficient computing resources, such as servers, cloud systems, and/or data centers for processing. However, this offloading method suffers from both high latency and network congestion in the IoT infrastructures. Recently edge computing has emerged to reduce the negative impacts of tasks offloading to remote computing systems. As edge computing is in close proximity to IoT devices, it can reduce the latency of task offloading and reduce network congestion. Yet, edge computing has its drawbacks, such as the limited computing resources of some edge computing devices and the unbalanced loads among these devices. In order to effectively explore the potential of edge computing to support IoT applications, it is necessary to have efficient task management and load balancing in edge computing networks. In this dissertation research, an approach is presented to periodically distributing tasks within the edge computing network while satisfying the quality-of-service (QoS) requirements of tasks. The QoS requirements include task completion deadline and security requirement. The approach aims to maximize the number of tasks that can be accommodated in the edge computing network, with consideration of tasks’ priorities. The goal is achieved through the joint optimization of the computing resource allocation and network bandwidth provisioning. Evaluation results show the improvement of the approach in increasing the number of tasks that can be accommodated in the edge computing network and the efficiency in resource utilization. / Dissertation/Thesis / Doctoral Dissertation Computer Engineering 2018
193

VIPLE Extensions in Robotic Simulation, Quadrotor Control Platform, and Machine Learning for Multirotor Activity Recognition

January 2018 (has links)
abstract: Machine learning tutorials often employ an application and runtime specific solution for a given problem in which users are expected to have a broad understanding of data analysis and software programming. This thesis focuses on designing and implementing a new, hands-on approach to teaching machine learning by streamlining the process of generating Inertial Movement Unit (IMU) data from multirotor flight sessions, training a linear classifier, and applying said classifier to solve Multi-rotor Activity Recognition (MAR) problems in an online lab setting. MAR labs leverage cloud computing and data storage technologies to host a versatile environment capable of logging, orchestrating, and visualizing the solution for an MAR problem through a user interface. MAR labs extends Arizona State University’s Visual IoT/Robotics Programming Language Environment (VIPLE) as a control platform for multi-rotors used in data collection. VIPLE is a platform developed for teaching computational thinking, visual programming, Internet of Things (IoT) and robotics application development. As a part of this education platform, this work also develops a 3D simulator capable of simulating the programmable behaviors of a robot within a maze environment and builds a physical quadrotor for use in MAR lab experiments. / Dissertation/Thesis / Masters Thesis Computer Science 2018
194

A Flexible FPGA-Assisted Framework for Remote Attestation of Internet Connected Embedded Devices

Patten, Jared Russell 01 March 2018 (has links)
Embedded devices permeate our every day lives. They exist in our vehicles, traffic lights, medical equipment, and infrastructure controls. In many cases, improper functionality of these devices can present a physical danger to their users, data or financial loss, etc. Improper functionality can be a result of software or hardware bugs, but now more than ever, is often the result of malicious compromise and tampering, or as it is known colloquially "hacking". We are beginning to witness a proliferation of cyber-crime, and as more devices are built with internet connectivity (in the so called "Internet of Things"), security should be of the utmost concern. Embedded devices have begun to seamlessly merge with our daily existence. Therefore the need for security grows as it more directly affects the safety of our data, property, and even physical health. This thesis presents an FPGA-assisted framework for remote attestation, a security service that allows a remote device to prove to a verifying entity that it can be trusted. In other words, it presents a protocol by which a device (be it an insulin pump, vehicle, etc.) can prove to a user (or other entity) that it can be trusted - i.e. that it has not been "hacked". This is accomplished through executable code integrity verification and run-time monitoring. In essence, the protocol verifies that a device is running authorized and untampered software and makes it known to a verifier in a trusted fashion. We implement the protocol on a physical device to demonstrate its feasibility and to examine its performance impact.
195

Arquitectura tecnológica basada en internet of things para monitorear las jornadas de pesca artesanal / Technological architecture based on internet of things to monitor the journeys of artisanal fishing

Ambrosio Mallqui, Jaime Jesus, Preguntegui Martinez, Leysa Jimena 27 September 2019 (has links)
En el Perú, la actividad pesquera artesanal es realizada por personas, grupos o pequeñas empresas y es definida como aquella que se realiza con o sin el empleo de embarcaciones. En caso de emplearlas, sus capacidades de bodega pueden llegar hasta 32,6 m3 de volumen y hasta 15 m de eslora con predominancia al trabajo manual durante la faena de pesca (IMARPE, 2017). Esta actividad, se caracteriza por no contar con tecnología o contar con tecnología precaria debido a la reducida cantidad de capital y energía. Por otro lado, cuentan con pequeñas embarcaciones de pesca, faenas de pesca cortas, áreas de pesca cercanas a la costa y su producción es para el consumo local. (Universidad del Pacífico, 2015). En el último censo realizado por PRODUCE e INEI se tenía cerca de 44.161 pescadores artesanales (IMARPE, 2017). Esta actividad, se ha convertido en un sector importante porque contribuye a la economía (IMARPE, 2017), especialmente en zonas costeras y a nivel nacional por su contribución a los índices de empleos (Universidad del Pacífico, 2015), contribuyendo a la reducción de la pobreza y a la seguridad alimenticia del país (FAO, 2016). Por tal motivo, el propósito del proyecto es implementar una arquitectura tecnológica basada en Internet of Things para monitorear las jornadas de pesca artesanal por medio de sensores y controladores. La motivación del presente trabajo radica en dos puntos importantes: Primero, brindar una infraestructura tecnológica a los pescadores artesanales. Segundo, monitorear las actividades de los pescadores artesanales. / In Peru, the artisanal fishing activity is carried out by individuals, groups, relatives or small businesses and is carried out with or without the use of boats. In case of using them, the capacity of boat can reach up to 32.6 m3 of volume and up to 15 m of length with predominance to manual work during the fishing operation (IMARPE, 2017). This activity is characterized by not having technology or having precarious technology due to the reduced amount of capital and energy. On the other hand, they have small fishing boats, short fishing operations, fishing areas near the shore and their production is for local consumption. (Universidad del Pacífico, 2015). In the last census conducted by PRODUCE and INEI there were about 44,161 artisanal fishermen (IMARPE, 2017). This activity has become an important sector because it contributes to the economy (IMARPE, 2017), especially in coastal areas and at the national level for its contribution to the indexes of employment (Universidad del Pacífico, 2015), contributing to the reduction of poverty and food security of the country (FAO, 2016). For this reason, the purpose of the project is to implement a technological architecture based on Internet of Things to monitor the journeys of artisanal fishing through sensors and controllers. The motivation of this work lies in two important points: First, to provide a technological infrastructure to artisanal fishermen. Second, to monitor the activities of artisanal fishermen. / Tesis
196

Cloud Services for Building the Modern Internet of Things : An Examination of IoT Cloud Service Providers

Sääf, Alexander January 2019 (has links)
As the IoT has grown in popularity, modern Cloud Providers have begun offering IoT-specific features. These features could provide IoT developers with a lot of aid, but they are new and relatively unexplored. This study aims to explore these IoT-specific features in order to build a better foundation for developers looking to leverage them to improve their IoT systems or development process. To do this, a literature study combined with a case study was carried out. The literature study gives insight into the current research around IoT and IoT cloud providers, for example with common issues and possible applications. The case study provides a reference of how a simple proof-of-concept system can be developed using two of the available providers: AWS IoT and Azure IoT.
197

Système avancé de cryptographie pour l'internet des objets ultra-basse consommation / An innovative lightweight cryptography system for Internet-of-Things ULP applications

Bui, Duy-Hieu 17 January 2019 (has links)
L'Internet des objets (IoT : Internet-of-Things) a été favorisé par les progrès accélérés dans les technologies de communication, les technologies de calcul, les technologies de capteurs, l'intelligence artificielle, l'informatique en nuage et les technologies des semi-conducteurs. En générale, l'IoT utilise l'informatique en nuage pour traitant les données, l'infrastructure de communication (y compris l’Internet) et des nœuds de capteurs pour collecter des données, de les envoyer de l'infrastructure du réseau à l’Internet, et de recevoir des commandes pour réagir à l'environnement. Au cours de ses opérations, l'IoT peut collecter, transmettre et traiter des données secrètes ou privées, ce qui pose des problèmes de sécurité. La mise en œuvre des mécanismes de sécurité pour l'IoT est un défi, car les organisations de l’IoT incluent des millions de périphériques intégrés à plusieurs couches, chaque couche ayant des capacités de calcul et des exigences de sécurité différentes. En outre, les nœuds de capteurs dans l'IoT sont conçus pour être des périphériques limités par une batterie, avec un budget de puissance, des calculs et une empreinte mémoires limités pour réduire les coûts d’implémentation. L'implémentation de mécanismes de sécurité sur ces appareils rencontre même plus de défis. Ce travail est donc motivé pour se concentrer sur l’implémentation du cryptage des données afin de protéger les nœuds et les systèmes de capteurs IoT en tenant compte du coût matériel, du débit et de la consommation d’énergie. Pour commencer, un crypto-accélérateur de chiffrement de bloc ultra-basse consommation avec des paramètres configurables est proposé et implémenté dans la technologie FDSOI ST 28 nm dans une puce de test, qui est appelée SNACk, avec deux modules de cryptographie : AES et PRESENT. L’AES est un algorithme de cryptage de données largement utilisé pour l’Internet et utilisé actuellement pour les nouvelles propositions IoT, tandis que le PRESENT est un algorithme plus léger offrant un niveau de sécurité réduit mais nécessitant une zone matérielle beaucoup plus réduite et une consommation très bas. Le module AES est une architecture de chemin de données 32 bits contenant plusieurs stratégies d'optimisation prenant en charge plusieurs niveaux de sécurité, allant des clés 128 bits aux clés 256 bits. Le module PRESENT contient une architecture à base arrondie de 64 bits pour optimiser son débit. Les résultats mesurés pendant cette thèse indiquent que ce crypto-accélérateur peut fournir un débit moyen (environ 20 Mbits/s au 10 MHz) tout en consommant moins de 20 µW dans des conditions normales et une sous-pJ d’énergie par bit. Cependant, la limitation du crypto-accélérateur réside dans le fait que les données doivent être lues dans le crypto-accélérateur et réécrites en mémoire, ce qui augmente la consommation d'énergie. Après cela, afin de fournir un haut niveau de sécurité avec une flexibilité et une possibilité de configuration pour s’adapter aux nouvelles normes et pour atténuer les nouvelles attaques, ces travaux portent sur une approche novatrice de mise en œuvre de l’algorithme de cryptographie utilisant la nouvelle SRAM proposée en mémoire. Le calcul en mémoire SRAM peut fournir des solutions reconfigurables pour mettre en œuvre diverses primitives de sécurité en programmant les opérations de la mémoire. Le schéma proposé consiste à effectuer le chiffrement dans la mémoire en utilisant la technologie Calcul en Mémoire (In-Memory-Computing). Ce travail illustre deux mappages possibles de l'AES et du PRESENT à l'aide du calcul en mémoire. / The Internet of Things (IoT) has been fostered by accelerated advancements in communication technologies, computation technologies,sensor technologies, artificial intelligence, cloud computing, and semiconductor technologies. In general, IoT contains cloud computing to do data processing, communication infrastructure including the Internet, and sensor nodes which can collect data, send them through the network infrastructure to the Internet, and receive controls to react to the environment. During its operations, IoT may collect, transmit and process secret data, which raise security problems. Implementing security mechanisms for IoT is challenging because IoT organizations include millions of devices integrated at multiple layers, whereas each layer has different computation capabilities and security requirements. Furthermore, sensor nodes in IoT are intended to be battery-based constrained devices with limited power budget, limited computation, and limited memory footprint to reduce costs. Implementing security mechanisms on these devices even encounters more challenges. This work is therefore motivated to focus on implementing data encryption to protect IoT sensor nodes and systems with the consideration of hardware cost, throughput and power/energy consumption. To begin with, a ultra-low-power block cipher crypto-accelerator with configurable parameters is proposed and implemented in ST 28nm FDSOI technology in SNACk test chip with two cryptography modules: AES and PRESENT. AES is a widely used data encryption algorithm for the Internet and currently used for new IoT proposals, while PRESENT is a lightweight algorithm which comes up with reduced security level but requires with much smaller hardware area and lower consumption. The AES module is a 32-bit datapath architecture containing multiple optimization strategies supporting multiple security levels from 128-bit keys up to 256-bit keys. The PRESENT module contains a 64-bit round-based architecture to maximize its throughput. The measured results indicate that this crypto-accelerator can provide medium throughput (around 20Mbps at 10MHz) while consumes less than 20uW at normal condition and sub-pJ of energy per bit. However, the limitation of crypto-accelerator is that the data has to be read into the crypto-accelerator and write back to memory which increases the power consumption. After that, to provide a high level of security with flexibility and configurability to adapt to new standards and to mitigate to new attacks, this work looks into an innovative approach to implement the cryptography algorithm which uses the new proposed In-Memory-Computing SRAM. In-Memory Computing SRAM can provide reconfigurable solutions to implement various security primitives by programming the memory's operations. The proposed scheme is to carry out the encryption in the memory using the In-Memory-Computing technology. This work demonstrates two possible mapping of AES and PRESENT using In-Memory Computing.
198

Influence d'une architecture de type maître-esclave dans les problématiques de sécurité de l'Internet des objets / Influence of master-slave architecture in the Internet of things

Pittoli, Philippe 21 May 2019 (has links)
L'Internet des objets est un principe selon lequel des clients sur Internet peuvent contacter des objets intelligents de notre quotidien, comme des capteurs de température d'une pièce ou des ampoules connectées. Ces objets sont contraints en mémoire, en capacité de calcul et aussi en capacité de communication (taille des paquets, médium partagé). Le travail effectué se focalise sur des problématiques liées à ces contraintes. Lorsqu'un client souhaite envoyer une commande à un objet, il a le choix de s'y connecter directement (architecture bout-en-bout) ou de se connecter à une passerelle réseau (non contrainte en mémoire et en calculs) qui jouera le rôle d'intermédiaire entre les clients et les objets (architecture maître-esclave). Le travail effectué consiste à comprendre les différences entre ces deux architectures et leur viabilité dans des réseaux de l'Internet des Objets. / The Internet of things is a network design where "things" are connected to the Internet, such as thermometers or lights. These objects are constrained in memory, computational capacity and communication (packet size, shared medium). The thesis is focused on issues around those constraints. A client willing to send a request to an object may either establish a direct connection to the object (end-to-end architecture) or establish a connection to the network gateway, which is not constrained in memory or computation capabilities, and will be used as a broker between clients and objects (master-slave architecture). This purpose of the thesis is to understand and to spotlight the differences between those two kinds of architectures and to determine their viability in an IoT context.
199

MODELING AND SECURITY IN CLOUD AND RELATED ECOSYSTEMS

Unknown Date (has links)
Software systems increasingly interact with each other, forming ecosystems. Cloud is one such ecosystem that has evolved and enabled other technologies like IoT and containers. Such systems are very complex and heterogeneous because their components can have diverse origins, functions, security policies, and communication protocols, which makes it difficult to comprehend, utilize and consequently secure them. Abstract architectural models can be used to handle this complexity and heterogeneity but there is lack of work on precise, implementation/vendor neutral and holistic models which represent ecosystem components and their mutual interactions. We attempted to find similarities in systems and generalize to create abstract models for adding security. We represented the ecosystem as a Reference architecture (RA) and the ecosystem units as patterns. We started with a pattern diagram which showed all the components involved along with their mutual interactions and dependencies. We added components to the already existent Cloud security RA (SRA). Containers, being relatively new virtualization technology, did not have a precise and holistic reference architecture. We have built a partial RA for containers by identifying and modeling components of the ecosystem. Container security issues were identified from the literature as well as analysis of our patterns. We added corresponding security countermeasures to container RA as security patterns to build a container SRA. Finally, using container SRA as an example, we demonstrated an approach for RA validation. We have also built a composite pattern for fog computing that is an intermediate platform between Cloud and IoT devices. We represented an attack, Distributed Denial of Service (DDoS) using IoT devices, in the form of a misuse pattern which explains it from the attacker’s perspective. We found this modelbased approach useful to build RAs in a flexible and incremental way as components can be identified and added as the ecosystems expand. This provided us better insight to analyze security issues across boundaries of individual ecosystems. A unified, precise and holistic view of the system is not just useful for adding or evaluating security, this approach can also be used to ensure compliance, privacy, safety, reliability and/or governance for cloud and related ecosystems. This is the first work we know of where patterns and RAs are used to represent ecosystems and analyze their security. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection
200

Exploring Security, Privacy, and Reliability Strategies to Enable the Adoption of IoT

Kamin, Daud Alyas 01 January 2017 (has links)
The Internet of things (IoT) is a technology that will enable machine-to-machine communication and eventually set the stage for self-driving cars, smart cities, and remote care for patients. However, some barriers that organizations face prevent them from the adoption of IoT. The purpose of this qualitative exploratory case study was to explore strategies that organization information technology (IT) leaders use for security, privacy, and reliability to enable the adoption of IoT devices. The study population included organization IT leaders who had knowledge or perceptions of security, privacy, and reliability strategies to adopt IoT at an organization in the eastern region of the United States. The diffusion of innovations theory, developed by Rogers, was used as the conceptual framework for the study. The data collection process included interviews with organization IT leaders (n = 8) and company documents and procedures (n = 15). Coding from the interviews and member checking were triangulated with company documents to produce major themes. Through methodological triangulation, 4 major themes emerged during my analysis: securing IoT devices is critical for IoT adoption, separating private and confidential data from analytical data, focusing on customer satisfaction goes beyond reliability, and using IoT to retrofit products. The findings from this study may benefit organization IT leaders by enhancing their security, privacy, and reliability practices and better protect their organization's data. Improved data security practices may contribute to social change by reducing risk in security and privacy vulnerabilities while also contributing to new knowledge and insights that may lead to new discoveries such as a cure for a disease.

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