This study focuses on the Internet of Things (IoT) gateway; a common middleware solution that bridges the gap between physical sensors and devices to internet applications. There is a shown interest in understanding the characteristics of different types of gateway architectures both from the research field and the industry, particularly the IT-consulting firm Attentec in Linköping, Sweden. A study has also been made on the open source C library libuv, used in the common web runtime engine NodeJS. The library has been used to study how asynchronous I/O operations can be used to improve the IoT gateway performance. A set of three general architectural approaches are identified. Common internal and external properties are identified based on state-of-the-art gateway implementations found in the industry. All of these properties are taken into account when a general gateway implementation is developed that is proposed to mimic any architectural level implementation of the gateway. A set of performance tests are conducted on the implementation to observe how different configurations of the gateway affect throughput and response time of data transmitted from simulated devices. The results show that the properties of the gateway do affect throughput and response time significantly and that libuv overall helps implement one of the best performing gateway configurations.

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.

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.

Nos recherches se situent à l'intersection des sphères académiques et industrielles et des organismes de standardisation pour permettre la mise en place d'un Internet des objets (IoT) sécurisé et efficace.Nous étudions des solutions de sécurisation en parcourant les standards de manière ascendante.En premier lieu, nous constatons que l'accélération matérielle des algorithmes de cryptographie est nécessaire pour les équipements formant l'IoT car il permet une reduction de deux ordres de grandeur des durées de calcul.Le surcoût des opérations cryptographiques n'est cependant qu'un des facteurs qui gouverne la performance globale dans le contexte des systèmes en réseau.Nous montrons à travers l'implementation d'applications pratiques que les dispositifs de sécurité de la couche 2 n'augmentent que de quelques pourcents la dépense énergétique totale.Ceci est acceptable, même pour les systèmes les plus contraints, comme ceux utilisant la recuperation d'énergie ambiante.La sécurité de la couche 2 contraint de faire confiance à chacun des noeuds du chemin de communication comprenant potentiellement des éléments malveillants, nous devons donc protéger le flux de données par un mécanisme de bout en bout.Nous étudions le protocole DTLS, standard de l'IETF pour la sécurité de l'IoT.Nous contribuons aux discussions sur l'intérêt de DTLS dans les environnements contraints, à la fois dans les organismes de standardisation et de recherche.Nous évaluons DTLS de manière étendue avec différents réseaux à cycle d'activité ou duty cycle au travers d'expérimentations, d'émulations et d'analyses.De manière surprenante, nos résultats démontrent la très faible performance de DTLS dans ces réseaux où l'efficacité énergétique est primordiale.Comme un client et un serveur DTLS échangent beaucoup de paquets de signalisation, la connection DTLS prends entre quelques secondes et quelques dizaines de secondes, ceci pour plusieurs des protocoles étudiés.DTLS a été conçu pour les communications de bout en bout dans l'Internet classique, contrairement au nouveau protocol CoAP qui lui est destiné à des machines contraintes en facilitant le traffic asynchrone, les communications de groupe et le besoin de stockage intermédiaire.Donc, en plus du problème de performance, l'architecture de sécurité basée sur DTLS n'est pas capable de répondre aux contraintes de ces dispositifs et CoAP devient inutilisable.Nous proposons une architecture qui s'appuie à la fois sur une approche centrée sur le contenu et sur la notion classique de connection.L'échange des clefs est fait à travers des canaux sécurisés établis par DTLS, mais la notion d'états entre les entités de communication est supprimée grâce au concept d'objets sécurisés.Le mécanisme proposé resiste aux attaques par rejeu en regroupant les capacités de controle d'accès avec les en-tetes de communication CoAP.OSCAR, notre architecture à objets sécurisés, supporte intrinsèquement les communications de groupe et le stockage intermédiaire, sans perturber le fonctionnement à cycle d'activité de la radio des équipements contraintes.Les idées d'OSCAR sont discutés par les groupes de standardisation de l'Internet en vue d'être intégrées dans les standards à venir. / Our research explores the intersection of academic, industrial and standardization spheres to enable secure and energy-efficient Internet of Things. We study standards-based security solutions bottom-up and first observe that hardware accelerated cryptography is a necessity for Internet of Things devices, as it leads to reductions in computational time, as much as two orders of magnitude. Overhead of the cryptographic primitives is, however, only one of the factors that influences the overall performance in the networking context. To understand the energy - security tradeoffs, we evaluate the effect of link-layer security features on the performance of Wireless Sensors Networks. We show that for practical applications and implementations, link-layer security features introduce a negligible degradation on the order of a couple of percent, that is often acceptable even for the most energy-constrained systems, such as those based on harvesting.Because link-layer security puts trust on each node on the communication path consisted of multiple, potentially compromised devices, we protect the information flows by end-to-end security mechanisms. We therefore consider Datagram Transport Layer Security (DTLS) protocol, the IETF standard for end-to-end security in the Internet of Things and contribute to the debate in both the standardization and research communities on the applicability of DTLS to constrained environments. We provide a thorough performance evaluation of DTLS in different duty-cycled networks through real-world experimentation, emulation and analysis. Our results demonstrate surprisingly poor performance of DTLS in networks where energy efficiency is paramount. Because a DTLS client and a server exchange many signaling packets, the DTLS handshake takes between a handful of seconds and several tens of seconds, with similar results for different duty cycling protocols.But apart from its performance issues, DTLS was designed for point-to-point communication dominant in the traditional Internet. The novel Constrained Ap- plication Protocol (CoAP) was tailored for constrained devices by facilitating asynchronous application traffic, group communication and absolute need for caching. The security architecture based on DTLS is, however, not able to keep up and advanced features of CoAP simply become futile when used in conjunction with DTLS. We propose an architecture that leverages the security concepts both from content-centric and traditional connection-oriented approaches. We rely on secure channels established by means of DTLS for key exchange, but we get rid of the notion of “state” among communicating entities by leveraging the concept of object security. We provide a mechanism to protect from replay attacks by coupling the capability-based access control with network communication and CoAP header. OSCAR, our object-based security architecture, intrinsically supports caching and multicast, and does not affect the radio duty-cycling operation of constrained devices. Ideas from OSCAR have already found their way towards the Internet standards and are heavily discussed as potential solutions for standardization.

Background Wearable technology, which is a part of the Internet of Things (IoT), appears to be an upcoming trend with increasing importance within the business world. Nevertheless, no clear business model for companies working with wearables had been defined yet taking the influences wearables have on businesses and especially their value proposition into consideration. Purpose The purpose of this thesis is to offer input to the lack of existing literature within business models and wearables technology. The aim is to unfold a general business model that can be used within wearable companies/IoT businesses and show the influence these technologies have on them. Methodology In order to conduct an empirical research a multiple case study has been conducted, based on semi-structured interviews with eight companies, which core business consists out of wearable technology. The frameworks on business models by Gassmann et al (2014) and Osterwalder and Pigneur (2010) serve as the basis for this study and its analysis, which is based on a grounded theory approach. Results It appears that a great amount of similarities can be found through the cross-case analysis between the cases. This makes the construction of a new business model possible. The unfolded model gives also a new contribution to the theory of Hui (2014) regarding a new area of value creation and value capture within IoT businesses.

Um dos principais desafios de pesquisa na UbiComp consiste em fornecer mecanismos para a ciência de contexto que promovam o desenvolvimento de aplicações que reajam de acordo com a dinâmica do ambiente de interesse do usuário. Para manter o conhecimento a respeito desse ambiente, a área da UbiComp pressupõe a utilização de informações produzidas e disponibilizadas em diferentes localizações, o tempo todo. Nesse sentido, os recentes avanços na área da Internet das Coisas (IoT) têm proporcionado uma crescente disponibilidade de sensores conectados em rede, os quais são potenciais produtores de informações contextuais do ambiente para aplicações ubíquas. Com essa motivação, nessa tese é apresentado o COIOT, um middleware para Internet das Coisas concebido com o objetivo de gerenciar a coleta e o processamento das informações contextuais do ambiente físico, bem como a atuação remota sobre o mesmo. O COIOT foi idealizado considerando os trabalhos previamente desenvolvidos pelo grupo de pesquisa GPPD (Grupo de Processamento Paralelo e Distribuído) da UFRGS, particularmente o middleware EXEHDA (Execution Environment for Highly Distributed Applications). Na concepção do COIOT foi adotada uma abordagem distribuída de processamento de contexto que contempla tanto as premissas da IoT quanto as demandas das aplicações da UbiComp. A arquitetura proposta também contempla o gerenciamento de eventos distribuídos através de regras e triggers para tratar as mudanças de estados dos contextos de interesse. Além disso, a arquitetura proposta gerencia outros aspectos importantes nos cenários da IoT, como o tratamento da interoperabilidade, da heterogeneidade, apoio ao controle da escalabilidade e descoberta de recursos. As principais contribuições desta tese são: (i) a concepção de uma arquitetura para IoT capaz de realizar de forma distribuída tanto a coleta e processamento das informações contextuais, como a atuação remota no meio a fim de atender as aplicações da UbiComp e, (ii) a proposição de um modelo de processamento de eventos distribuídos adequado aos cenários da IoT. Para avaliar a arquitetura do COIOT foram realizados dois estudos de caso na área da agricultura. O primeiro estudo de caso foi desenvolvido em ambiente de produção a partir de demandas de pesquisadores da área da agricultura, particularmente da análise de sementes. Já o segundo estudo de caso teve como cenário de testes ambientes da viticultura de precisão. / One of the main research challenges in UbiComp is to provide mechanisms for context-aware to promote the development of applications that react according to the dynamics of user interest environment. To keep the knowledge of this environment, the area of UbiComp presupposes the use of information produced and made available in different locations, all the time. In this sense, the recent advances in the field of Internet of Things (IoT) have provided an increasing availability of sensors and actuators networked. These sensors are potential producers of contextual information. With this motivation, this thesis is presented the CoIoT, a middleware for Internet of Things (IoT) designed in order to manage the collect and processing of contextual information of the physical environment as well as remote actuation on it. The CoIoT was designed considering the work previously developed by the research group GPPD (Parallel Processing Group and distributed) of UFRGS, particularly middleware EXEHDA (Execution Environment for Highly Distributed Applications). In designing the CoIoT it was adopted a distributed approach of context processing that includes both the principles of IoT as the demands of the applications of UbiComp. The proposed architecture also includes rules based and triggers mechanisms to deal with events that characterize the changes of states of the contexts of interest. In addition, the proposed architecture manages other important aspects of IoT scenarios such as the treatment of interoperability, heterogeneity, support the control of scalability and resource discovery. Until now, the central contributions of this thesis include: (i) the design of an architecture for IoT able to perform distributed way both the collect and processing of contextual information, such as remote actuation in the environment in order to meet UbiComp applications and, (ii) the proposition of a distributed event processing model appropriate to the IoT scenarios. In order to evaluate the CoIoT architecture, two case studies were carried out in the area of agriculture. The first case study was developed in a production environment based on the demands of agricultural researchers, particularly seed analysis. On the other hand, the second case study was based on precision testing of viticulture environments.

IoT is a rapidly growing area with products in the consumer, commercial and industrial market. Collecting data with multiple small and often battery-powered devices sets new challenges for both security and communication. There has been a distinct lack of a IoT specific communication protocols. The industry has had to use bulky interfaces not suitable for resource-constrained devices. MQTT is a standardised communication protocol made for the IoT industry. MQTT does however not have built-in security and it is up to the developers to implement a suitable security countermeasure. To evaluate how different security countermeasures impact MQTT in complexity, current consumption and security the following research questions are answered. How do you derive a measurement from the SEF that can be compared with a current consumption measurement? Which level of security, according to the SEF, will RSA, AES and TLS provide to MQTT when publishing a message to a broker? What level of complexity is added to MQTT when using chosen security countermeasure? Which of the analysed security countermeasure upholds an adequate security level while also having a low current consumption? To answer the above research questions an experiment approach has been used. Implementations of TLS, RSA and AES have been evaluated to measure how they affect the security level and current consumption of an MQTT publication, compared to no security countermeasures at all.Both RSA and AES had the same security level, but the current consumption for RSA was four times higher. The experiment showed that the security level is significantly higher for TLS, while it also has the highest current consumption. The security countermeasure evaluated differs greatly. TLS provides complete protections, while RSA and AES lacks authentication and does not ensure integrity and non-repudiation.Even if the current consumption for TLS is higher, the security it provides make it unreasonable to recommend any of the other security countermeasure implementations.

Internet of Things (IoT) means that physical objects will be able to interact and communicate via embedded systems. This will lead to a distributed network of devices that can communicate with both humans and each other. One application area is in improving supply chain management. The goal in supply chains is to move a product or a service from the producer to the customer as efficient as possible. Implementation of IoT will have many benefits but it also raises security issues that can affect integrity, security and privacy for both individuals and companies. In 2009, Satoshi Nakamoto created bitcoin and more importantly, blockchain. Blockchain is a ledger of facts, data is not stored in only one network with a common processor, but it is distributed among all the clients on the network. This technology may be a solution to some problems that IoT are facing. This paper looks into up to date research of blockchain and IoT with the purpose to study blockchain as a potential solution to secure IoT data management within supply chains. Both blockchain and IoT are relatively new research areas with little existing research, which support our use of a qualitative inductive method. Semi-structured interviews, which will be further explained in the methodology section, have been conducted with people working within the fields of blockchain, IoT and supply chain. The result indicates that blockchain can be used to secure data management within any given supply chain that uses IoT technology, but blockchain should be seen as a tool, and not as a complete solution. Many of the security issues within IoT are related to the devices and blockchain will not be able to provide a solution to these problems. Blockchain can however be used for handling information, securing identities, traceability of goods, transactions being made without human interaction, automated storage management and time stamped actions to name some examples. There are still barriers to make these benefits work in reality but there is a lot of research currently on-going, trying to make it happen.

Algumas palavras e definições comumente utilizadas quando se está falando de Software-Defined Networking, como programabilidade, flexibilidade, ou gerenciamento centralizado, parecem muito apropriadas ao contexto de um outro paradigma de rede: Internet of Things. Em redes domésticas já não é incomum a existência de dispositivos projetados para segurança, climatização, iluminação, monitoramento de saúde e algumas formas de automação que diferem entre si em diversos aspectos, como no modo de operar e de se comunicar. Lidar com este tipo de cenário, que pode diferir bastante daquilo que estamos acostumados na gerência de redes e serviços, fazendo uso dos recursos tradicionais como ferramentas e protocolos bem estabelecidos, pode ser difícil e, em alguns casos, inviável. Com o objetivo de possibilitar o monitoramento remoto de pacientes com doenças crônicas através de dispositivos de healthcare disponíveis no mercado, uma proposta de middleware foi desenvolvida em um projeto de pesquisa para contornar as limitações relacionadas à interoperabilidade, coleta de dados, gerência, segurança e privacidade encontradas nos dispositivos utilizados. O middleware foi projetado com o intuito de executar em access points instalados na casa dos pacientes. Contudo, as limitações de hardware e software do access point utilizado refletem no desenvolvimento, pois restringem o uso de linguagens de programação e recursos que poderiam agilizar e facilitar a implementação dos módulos e dos mecanismos necessários. Os contratempos encontrados no desenvolvimento motivaram a busca por alternativas, o que resultou na refatoração do middleware através de Software-Defined Networking, baseando-se em trabalhos que exploram o uso desse paradigma em redes domésticas. O objetivo deste trabalho é verificar a viabilidade da utilização de Software-Defined Networking no contexto de Internet of Things, mais especificamente, aplicado ao serviço de monitoramento de pacientes da proposta anterior e explorar os possíveis benefícios resultantes. Com a refatoração, a maior parte da carga de serviços da rede e do monitoramento foi distribuída entre servidores remotos dedicados, com isso os desenvolvedores podem ir além das restrições do access point e fazer uso de recursos antes não disponíveis, o que potencializa um processo de desenvolvimento mais ágil e com funcionalidades mais complexas, ampliando as possibilidades do serviço. Adicionalmente, a utilização de Software-Defined Networking proporcionou a entrega de mais de um serviço através de um único access point, escalabilidade e autonomia no gerenciamento das redes e dos dispositivos e na implantação de serviços, fazendo uso de recursos do protocolo OpenFlow, e a cooperação entre dispositivos e serviços a fim de se criar uma representação digital mais ampla do ambiente monitorado. / Some words and definitions usually employed when talking about Software-Defined Networking such as programmability, frexibility, or centralized management sound very appropriate to the context of another network paradigm: Internet of Things. The presence of devices designed for security, air conditioning, lighting, health monitoring and some other automation resources have become common in home networks; those devices may be different in many ways, such as the way they operate and communicate, between others. Dealing with this kind of scenario may differ in many ways from what we are familiar regarding networking and services management; the use of traditional management tools and protocols may be hard or even unfeasible. Aiming to enable the health monitoring of patients with chronical illnesses through using off-the-shelf healthcare devices a middleware proposal was developed in a research project to circumvent interoperability, data collecting, management, security and privacy issues found in employed devices. The middleware was designed to run on access points in the homes of the patients. Although hardware and software limitations of the used access points reflect on the development process, because they restrict the use of programming languages and resources that could be employed to expedite the implementation of necessary modules and features. Development related mishaps have motivated the search for alternatives resulting in the middleware refactoring through Software-Defined Networking, based on previous works where that paradigm is used in home networks. This work aims to verify the feasability of the employment of Software- Defined Networking in the Internet of Things context, and its resulting benefits; specifically in the health monitoring of chronic patients service from the previous proposal. After refactoring most of the network and services load was distributed among remote dedicated servers allowing developers to go beyond the limitations imposed by access points constraints, and to make use of resources not available before enabling agility to the development process; it also enables the development of more complex features expanding services possibilities. Additionally Software-Defined Networking employment provides benefits such as the delivering of more than only one service through the same access point; scalability and autonomy to the network and devices monitoring, as to the service deployment through the use of OpenFlow resources; and devices and services cooperation enabling the built of a wider digital representation of the monitored environment.

Set in the relatively new and fast developing field of investigation known as Internet of Things (IoT), this research starts by looking at the lack of critical and conceptual reflection on the area. With a main research question that challenges the underlying concepts of the IoT, the study develops a performative design framework to critique the field of investigation. The main corpus consists of: 1. speculative inquiry into the ontological dualisms of ‘objects’ and ‘things’ and the emerging social dimension of humans and non-humans; 2. the identification of an ontological-performative model based on the idea of Props; 3. the entanglement of theory and practice to construct a performative design framework, called the Internet of Props, which includes: an enabling platform (Smarter Planet Lab) and a set of design strategies (Transactional Props) to demonstrate and evaluate this model and framework; 4. a combined-evaluation conversational analysis methodology that assesses the performativity of the setting and the Props, through linguistic and socio-behavioural studies. Inspired by the concepts of ontological theatre, the entanglement of humans and non-humans, and the Internet of People; the IoT is imagined and performed in a theory-driven, practice-based investigation of the Internet of Props, which aims to bring new theoretical and practical knowledge for the future of the IoT.