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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.
301

A Secure Computing Platform for Building Automation Using Microkernel-based Operating Systems

Wang, Xiaolong 09 November 2018 (has links)
Building Automation System (BAS) is a complex distributed control system that is widely deployed in commercial, residential, industrial buildings for monitoring and controlling mechanical/electrical equipment. Through increasing industrial and technological advances, the control components of BAS are becoming increasingly interconnected. Along with potential benefits, integration also introduces new attack vectors, which tremendous increases safety and security risks in the control system. Historically, BAS lacks security design and relies on physical isolation and "security through obscurity". These methods are unacceptable with the "smart building" technologies. The industry needs to reevaluate the safety and security of the current building automation system, and design a comprehensive solution to provide integrity, reliability, and confidentiality on both system and network levels. This dissertation focuses on the system level in the effort to provide a reliable computing foundation for the devices and controllers. Leveraged on the preferred security features such as, robust modular design, small privilege code, and formal verifiability of microkernel architecture, this work describes a security enhanced operating system with built-in mandatory access control and a proxy-based communication framework for building automation controllers. This solution ensures policy-enforced communication and isolation between critical applications and non-critical applications in a potentially hostile cyber environment.
302

IT i bilen : En fallstudie av ubikvitär datorisering

Gyllhamn, Noel, Jonsson, Klas January 2012 (has links)
This paper aims to study the possibilities and challenges the car industry has to face with applying information technology in cars. The goal is to describe and analyse all the existing technology in the cars out on the market today as well as future possible technologies in cars. By interviewing people who has been working or are working with information technology in cars, we aim to clarify the obstacles and opportunities in the process of implementing informatics in cars. With this knowledge we want to learn more about Ubiquitous computing and how humans interact with Ubiquitous computers today and will be interacting in the future. Technology has a rapid development pace and we find it interesting to examine how the car industry can keep up with the rapid development pace of technology.
303

Förening av trådlösa mesh-nätverk och PLC-miljö för industriella behov / Composition of wireless mesh networks and PLC for industrial needs

Polya, Alexander, Lindén, Anders January 2015 (has links)
In conjunction with the possibility of inexpensive wireless communication, many products of tomorrow are developed with the support for wireless communication. The technology enables the possibilty of wireless communication to small plattforms at a realistic price. The cheap connectivity allows for great creativity and gives the developers imagination a wide discretion in the development of new products. This thesis aims to evaluate how the serial communication protocol Modbus RTU - RS232, performs and behaves when transported through meshed networks (Atmel lightweight mesh will be used in this thesis). The work was commissioned by M2M Solutions in J¨onk¨oping. The report will answer the following questions1. How does Modbus RTU behaves when transported through a meshed network. 2. How does Modbus RTU preform when transported through Atmel Lightweight Mesh.The authors have chosen to conduct action research to answer established questions. A test system consisting of both hardware and software was designed and created. With this system, several different tests were conducted and the results were observed and subjected to reflection. The different tests varied the distance, the network’s composition and location of the network infrastructure. Through observation of the test system and evaluation of the recorded data conclusions concering Modbus RTU’s performance and behavior during transport in Atmel lightweigh mesh has been drawn. The test system has been designed with the help of clients and previously made research. Modbus behaves nominally during transportation through Atmel lightweight mesh. Before the network is fully established, an inability to transport data has beend observed. The performance is evaluated by the time it takes to send data, the time is greatly affected by the following factors; Network composition and changes in signal strength (that creates changes in transport routes). For each additional node that traffic is transported through an increase of 5-10ms in the responstime was noted. The network’s ability to change the transport route is also expected to increase performance. The wireless communication provides a longer range than during transportation by standard conventional cable.Considering the results, the authors believe that Modbus RTU has the potential for use in transportation through wireless, meshed networks. One possible scenario is when several Modbus RTU masters are beeing used and data needs to be transported over large distances.
304

Information Centric Data Collection and Dissemination Fabric for Smart Infrastructures

Nigam, Aakash 09 December 2013 (has links)
Evolving smart infrastructures requires both content distribution as well as event notification and processing support. Content Centric Networking (CCN), built around named data, is a clean slate network architecture for supporting future applications. Due to its focus on content distribution, CCN does not inherently support Publish-Subscribe event notification, a fundamental building block in computer mediated systems and a critical requirement for smart infrastructure applications. While semantics of content distribution and event notification require different support systems from the underlying network infrastructure, content distribution and event notification can still be united by leveraging similarities in the routing infrastructure. Our Extended-CCN architecture(X-CCN) realizes this to provide lightweight content based pub-sub service at the network layer, which is used to provide advanced publish/subscribe services at higher layers. Light weight content based pub-sub and CCN communication at network layer along with advanced publish/subscribe together are presented as data fabric for the smart infrastructures applications.
305

Enabling Ultra Large-Scale Radio Identification Systems

ALI, KASHIF 31 August 2011 (has links)
Radio Frequency IDentification (RFID) is growing prominence as an automated identification technology able to turn everyday objects into an ad-hoc network of mobile nodes; which can track, trigger events and perform actions. Energy scavenging and backscattering techniques are the foundation of low-cost identification solutions for RFIDs. The performance of these two techniques, being wireless, significantly depends on the underlying communication architecture and affect the overall operation of RFID systems. Current RFID systems are based on a centralized master-slave architecture hindering the overall performance, scalability and usability. Several proposals have aimed at improving performance at the physical, medium access, and application layers. Although such proposals achieve significant performance gains in terms of reading range and reading rates, they require significant changes in both software and hardware architectures while bounded by inherited performance bottlenecks, i.e., master-slave architecture. Performance constraints need to be addressed in order to further facilitate RFID adoption; especially for ultra large scale applications such as Internet of Things. A natural approach is re-thinking the distributed communication architecture of RFID systems; wherein control and data tasks are decoupled from a central authority and dispersed amongst spatially distributed low-power wireless devices. The distributed architecture, by adjusting the tag's reflectivity coefficient creates micro interrogation zones which are interrogated in parallel. We investigate this promising direction in order to significantly increase the reading rates and reading range of RFID tags, and also to enhance overall system scalability. We address the problems of energy-efficient tag singulations, optimal power control schemes and load aware reader placement algorithms for RFID systems. We modify the conventional set cover approximation algorithm to determine the minimal number of RFID readers with minimal overlapping and balanced number of tags amongst them. We show, via extensive simulation analysis, that our approach has the potential to increase the performance of RFID technology and hence, to enable RFID systems for ultra large scale applications. / Thesis (Ph.D, Computing) -- Queen's University, 2011-08-30 23:41:02.937
306

Information Centric Data Collection and Dissemination Fabric for Smart Infrastructures

Nigam, Aakash 09 December 2013 (has links)
Evolving smart infrastructures requires both content distribution as well as event notification and processing support. Content Centric Networking (CCN), built around named data, is a clean slate network architecture for supporting future applications. Due to its focus on content distribution, CCN does not inherently support Publish-Subscribe event notification, a fundamental building block in computer mediated systems and a critical requirement for smart infrastructure applications. While semantics of content distribution and event notification require different support systems from the underlying network infrastructure, content distribution and event notification can still be united by leveraging similarities in the routing infrastructure. Our Extended-CCN architecture(X-CCN) realizes this to provide lightweight content based pub-sub service at the network layer, which is used to provide advanced publish/subscribe services at higher layers. Light weight content based pub-sub and CCN communication at network layer along with advanced publish/subscribe together are presented as data fabric for the smart infrastructures applications.
307

Lightweight Security Solutions for the Internet of Things

Raza, 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.
308

Integration of Internet of Things technologies in warehouses : A multiple case study on how the Internet of Things technologies can efficiently be used in the warehousing processes

Bieringer, Alexandra, Müller, Linda January 2018 (has links)
No description available.
309

Programming Support for a Delay-Tolerant Web of Things / Support de programmation pour un Web des objets tolérant les délais

Auzias, Maël 03 October 2017 (has links)
L'internet des Objets (IoT) est habituellement présenté comme l'ensemble d'objets interconnectés à travers un réseau qui est, en pratique, Internet. Or, il existe beaucoup de cas où la connectivité est intermittente à cause des interfaces radio courte-portées et des contraintes d'économie d'énergie. L'architecture de réseautage tolérant les délais (DTN) ainsi que le Bundle Protocole (BP) sont considérés comme des solutions viables pour résoudre ce genre de challenges grâce au mécanisme store-carry-and-forward. Cette thèse vise à fournir des supports de programmation adaptés autant à l'IoT qu'au contexte DTN. Dans ce but, les challenges relevant du DTN et de l'IoT (DT-IoT) sont étudiés et quelques principes de design logiciels sont proposés. Ces principes ont pour but d'optimiser la réactivité et l'efficacité des applications ayant pour cible un contexte DT- IoT. La première contribution est la définition d'un support de programmation orienté ressources, nommé BoaP. Ce support fournit un protocole de requête/réponse grâce à une transposition de CoAP (Contrained Application Protocol). Cette transposition est composée d'ajustements fondamentaux et d'améliorations pour utiliser BP en tant que couche de transport. BoaP a été implémenté et testée dans un petit réseau physique. Une méthode pour évaluer des intergiciels dans des réseaux DTNs est présentée. Un outil implémentant cette méthode a été développé. Il repose sur une plateforme de virtualisation qui simule les contacts réseaux tout en émulant les nœuds du réseau. Cet outil a été utilisé pour exécuter des expériences pour évaluer la validité de BoaP. Enfin, un autre support de programmation est examiné. Celui-ci adopte une approche orientée service et respecte les contraintes REST (Representational State Transfer). Il se repose sur BoaP a été créé avec l'IoT en tête et est adapté à l’environnement DTN. La découverte exploite une interface de publications/souscriptions. Les descripteurs de services contiennent des champs spécifiques pour informer de la disponibilité de leur fournisseurs. / The Internet of Things (IoT) is usually presented as a set of THINGS interconnected through a network that is, in practice, Internet. However, there exist many contexts in which the connectivity is intermittent due to short-range wireless communication means or energy constraints. The Delay Tolerant Networking (DTN) architecture and the Bundle Protocol (BP) are known to overcome this communication challenge as they provide communication means by relying on a store-carry-and- forward mechanism. This thesis aims to provide programming supports adapted to both IoT and DTN contexts. For this, both DTN and IoT (DT-IoT) challenges are studied and several design principles are proposed. These principles aim to optimize reactivity and efficiency of applications targeting the DT-IoT context. The first contribution is the definition of a resource-oriented programming support, named BoaP, to enable a DT-IoT. It provides a protocol based on request/response thanks to a transposition of CoAP (Contrained Application Protocol). This transposition consists of fundamental adjustments and enhancements to use BP as the underlying transport protocol. BoaP has been implemented and tested in a small physical network. A method to evaluate middleware systems in DTNs is presented. A tool implementing this method has been developed. It relies on a virtualization platform that simulates network contacts and emulates network devices. This tool was used to run experimentations that assessed the validity of BoaP. Finally, another programming support is investigated. It follows a service-oriented approach and respects REST (Representational State Transfer) constraints. It is built on top of BoaP with IoT in mind and is adapted to DTN environments. Its discovery/advertisement exploits a publish/subscribe interface. Service descriptors contain specific fields to inform on the availability of the service providers. %Finally, requests are extended with some options to enforce conditions on geographic or time context.
310

In search of the DomoNovus : speculative designs for the computationally-enhanced domestic environment

Didakis, Stavros January 2017 (has links)
The home is a physical place that provides isolation, comfort, access to essential needs on a daily basis, and it has a strong impact on a person’s life. Computational and media technologies (digital and electronic objects, devices, protocols, virtual spaces, telematics, interaction, social media, and cyberspace) become an important and vital part of the home ecology, although they have the ability to transform the domestic experience and the understanding of what a personal space is. For this reason, this work investigates the domestication of computational media technology; how objects, systems, and devices become part of the personal and intimate space of the inhabitants. To better understand the taming process, the home is studied and analysed from a range of perspectives (philosophy, sociology, architecture, art, and technology), and a methodological process is proposed for critically exploring the topic with the development of artworks, designs, and computational systems. The methodology of this research, which consists of five points (Context, Media Layers, Invisible Matter, Diffusion, and Symbiosis), suggests a procedure that is fundamental to the development and critical integration of the computationally enhanced home. Accordingly, the home is observed as an ecological system that contains numerous properties (organic, inorganic, hybrid, virtual, augmented), and is viewed on a range of scales (micro, meso and macro). To identify the “choreographies” that are formed between these properties and scales, case studies have been developed to suggest, provoke, and speculate concepts, ideas, and alternative realities of the home. Part of the speculation proposes the concept of DomoNovus (the “New Home”), where technological ubiquity supports the inhabitants’ awareness, perception, and imagination. DomoNovus intends to challenge our understanding of the domestic environment, and demonstrates a range of possibilities, threats, and limitations in relation to the future of home. This thesis, thus, presents methods, experiments, and speculations that intend to inform and inspire, as well as define creative and imaginative dimensions of the computationally-enhanced home, suggesting directions for the further understanding of the domestic life.

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