179 research outputs found
Handling Inherent Delays in Virtual IoT Gateways
15th International Conference on Distributed Computing in Sensor Systems (DCOSS)Massive deployment of diverse ultra-low power wireless devices in different application areas has given rise to a plethora of heterogeneous architectures and communication protocols. It is challenging to provide convergent access to these miscellaneous collections of communicating devices. In this paper, we propose VGATE, an edge-based virtualized IoT gateway for bringing these devices together in a single framework using SDRs as technology agnostic radioheads. SDR platforms, however, suffer from large unpredictable delays. We design a GNU Radio-based IEEE 802.15.4 experimental setup using LimeSDR, where the data path is time-stamped at various points of interest to get a comprehensive understanding of the characteristics of the delays. Our analysis shows that GNU Radio processing and LimeSDR buffering delays are the major delays. We decrease the LimeSDR buffering delay by decreasing the USB transfer size but show that this comes at the cost of increased processing overhead. We modify the USB transfer packet size to investigate which USB transfer size provides the best balance between buffering delay and processing overhead across two different host computers. Our experiments show that for the best measured configuration the mean and jitter of latency decreases by 37% and 40% respectively for the host computer with higher processing resources. We also show that the throughput is not affected by these modifications.This work has been partially funded by the H2020 collaborative
Europe/Taiwan research project 5G-CORAL (grant num.
761586)
Performance Evaluation of Cognitive Radio Spectrum Sensing Techniques through a Rayleigh Fading Channel
In recent years, there has been a steep rise in the demand for bandwidth due to a sharp increase in the number of devices connected to the wireless network. Coupled with the expected commercialization of 5G services and massive adoption of IoT, the upsurge in the number of devices connected to the wireless network will continue to grow exponentially into billions of devices. To accommodate the associated demand for wireless spectrum as we step into this new era of wireless connectivity, traditional methods of spectrum utilization based on fixed and static allocation are no longer adequate. New innovative forms that support dynamic assignment of spectrum space on as-per-need basis are now paramount. Cognitive radio has emerged as one of the most promising techniques that allow flexible usage of the scarce spectrum resource. Cognitive radio allows unlicensed users to opportunistically access spectrum bands assigned to primary users when these spectrum bands are idle. As such, cognitive radio reduces the gap between spectrum scarcity and spectrum underutilization. The most critical function of cognitive radio is spectrum sensing, which establishes the occupation status of a spectrum band, paving the way for a cognitive radio to initiate transmission if the band is idle. The most common and widely used methods for spectrum sensing are energy detection, matched filter detection, cyclostationary feature detection and cooperative based spectrum sensing. This dissertation investigates the performance of these spectrum-sensing techniques through a Rayleigh fading channel. In a wireless environment, a Rayleigh fading channel models the propagation of a wireless signal where there is no dominant line of sight between the transmitter and receiver. Understanding the performance of spectrum sensing techniques in a real world simulation environment is important for both industry and academia, as this allows for the optimal design of cognitive radio systems capable of efficiently executing their function. MATLAB software provides an experimental platform for the fusion of various Rayleigh fading channel parameters that mimic real world wireless channel characteristics. In this project, a MATLAB environment test bed is used to simulate the performance for each spectrum sensing technique across a range of signal-to-noise values, through a Rayleigh fading channel with a given set of parameters for channel delay, channel gain and Doppler shift. Simulation results are presented as plots for probability of detection versus signal-tonoise ratio, receiver operating characteristics (ROC) curves and complementary ROC curves. A detailed performance analysis for each spectrum sensing technique then follows, with comparisons done to determine the technique that offers the best relative performance
Deploying RIOT operating system on a reconfigurable Internet of Things end-device
Dissertação de mestrado integrado em Engenharia Eletrónica Industrial e ComputadoresThe Internet of Everything (IoE) is enabling the connection of an infinity of
physical objects to the Internet, and has the potential to connect every single
existing object in the world. This empowers a market with endless opportunities
where the big players are forecasting, by 2020, more than 50 billion connected
devices, representing an 8 trillion USD market.
The IoE is a broad concept that comprises several technological areas and will
certainly, include more in the future. Some of those already existing fields are the
Internet of Energy related with the connectivity of electrical power grids, Internet
of Medical Things (IoMT), for instance, enables patient monitoring, Internet of
Industrial Things (IoIT), which is dedicated to industrial plants, and the Internet
of Things (IoT) that focus on the connection of everyday objects (e.g. home
appliances, wearables, transports, buildings, etc.) to the Internet.
The diversity of scenarios where IoT can be deployed, and consequently the
different constraints associated to each device, leads to a heterogeneous network
composed by several communication technologies and protocols co-existing on the
same physical space. Therefore, the key requirements of an IoT network are
the connectivity and the interoperability between devices. Such requirement is
achieved by the adoption of standard protocols and a well-defined lightweight network
stack. Due to the adoption of a standard network stack, the data processed
and transmitted between devices tends to increase. Because most of the devices
connected are resource constrained, i.e., low memory, low processing capabilities,
available energy, the communication can severally decrease the device’s performance.
Hereupon, to tackle such issues without sacrificing other important requirements,
this dissertation aims to deploy an operating system (OS) for IoT, the
RIOT-OS, while providing a study on how network-related tasks can benefit from
hardware accelerators (deployed on reconfigurable technology), specially designed
to process and filter packets received by an IoT device.O conceito Internet of Everything (IoE) permite a conexão de uma infinidade
de objetos à Internet e tem o potencial de conectar todos os objetos existentes no
mundo. Favorecendo assim o aparecimento de novos mercados e infinitas possibilidades,
em que os grandes intervenientes destes mercados preveem até 2020 a
conexão de mais de 50 mil milhões de dispositivos, representando um mercado de
8 mil milhões de dólares.
IoE é um amplo conceito que inclui várias áreas tecnológicas e irá certamente
incluir mais no futuro. Algumas das áreas já existentes são: a Internet of Energy
relacionada com a conexão de redes de transporte e distribuição de energia à
Internet; Internet of Medical Things (IoMT), que possibilita a monotorização de
pacientes; Internet of Industrial Things (IoIT), dedicada a instalações industriais
e a Internet of Things (IoT), que foca na conexão de objetos do dia-a-dia (e.g.
eletrodomésticos, wearables, transportes, edifícios, etc.) à Internet.
A diversidade de cenários à qual IoT pode ser aplicado, e consequentemente,
as diferentes restrições aplicadas a cada dispositivo, levam à criação de uma rede
heterogénea composto por diversas tecnologias de comunicação e protocolos a coexistir
no mesmo espaço físico. Desta forma, os requisitos chave aplicados às redes
IoT são a conectividade e interoperabilidade entre dispositivos. Estes requisitos
são atingidos com a adoção de protocolos standard e pilhas de comunicação bem
definidas. Com a adoção de pilhas de comunicação standard, a informação processada
e transmitida entre dispostos tende a aumentar. Visto que a maioria dos
dispositivos conectados possuem escaços recursos, i.e., memória reduzida, baixa
capacidade de processamento, pouca energia disponível, o aumento da capacidade
de comunicação pode degradar o desempenho destes dispositivos.
Posto isto, para lidar com estes problemas e sem sacrificar outros requisitos importantes,
esta dissertação pretende fazer o porting de um sistema operativo IoT,
o RIOT, para uma solução reconfigurável, o CUTE mote. O principal objetivo
consiste na realização de um estudo sobre os benefícios que as tarefas relacionadas
com as camadas de rede podem ter ao serem executadas em hardware via aceleradores
dedicados. Estes aceleradores são especialmente projetados para processar
e filtrar pacotes de dados provenientes de uma interface radio em redes IoT periféricas
Mission-Critical Communications from LMR to 5G: a Technology Assessment approach for Smart City scenarios
Radiocommunication networks are one of the main support tools of agencies that carry out
actions in Public Protection & Disaster Relief (PPDR), and it is necessary to update these
communications technologies from narrowband to broadband and integrated to information
technologies to have an effective action before society. Understanding that this problem
includes, besides the technical aspects, issues related to the social context to which these
systems are inserted, this study aims to construct scenarios, using several sources of
information, that helps the managers of the PPDR agencies in the technological decisionmaking
process of the Digital Transformation of Mission-Critical Communication considering
Smart City scenarios, guided by the methods and approaches of Technological Assessment
(TA).As redes de radiocomunicações são uma das principais ferramentas de apoio dos órgãos que
realizam ações de Proteção Pública e Socorro em desastres, sendo necessário atualizar essas
tecnologias de comunicação de banda estreita para banda larga, e integra- las às tecnologias
de informação, para se ter uma atuação efetiva perante a sociedade . Entendendo que esse
problema inclui, além dos aspectos técnicos, questões relacionadas ao contexto social ao qual
esses sistemas estão inseridos, este estudo tem por objetivo a construção de cenários,
utilizando diversas fontes de informação que auxiliem os gestores destas agências na tomada
de decisão tecnológica que envolve a transformação digital da Comunicação de Missão Crítica
considerando cenários de Cidades Inteligentes, guiado pelos métodos e abordagens de
Avaliação Tecnológica (TA)
A Game Theoretic Approach for Privacy Preserving Model in IoT-Based Transportation
International audienceInternet of Things (IoT) applications using sensors and actuators raise new privacy related threats such as drivers and vehicles tracking and profiling. These threats can be addressed by developing adaptive and context-aware privacy protection solutions to face the environmental constraints (memory, energy, communication channel, etc.), which cause a number of limitations of applying cryptographic schemes. This paper proposes a privacy preserving solution in ITS context relying on a game theory model between two actors (data holder and data requester) using an incentive motivation against a privacy concession, or leading an active attack. We describe the game elements (actors, roles, states, strategies, and transitions), and find an equilibrium point reaching a compromise between privacy concessions and incentive motivation. Finally, we present numerical results to analyze and evaluate the game theory-based theoretical formulation
Becoming a keystone: How incumbents can leverage technological change to create ecosystems
The proliferation of digital technology and automation in the 21st century has created a need to\ua0revisit established theories on value creation. Exponential advances in Internet of Things (IoT)\ua0technologies are dismantling firm- and industry-specific value creation processes. The firms\ua0developing digital technology-based products and services typically participate in broad\ua0networks, which allows them to integrate distinct systems and technologies to produce a focal\ua0value proposition. The purpose of this thesis is to explore how incumbents can leverage\ua0technological change to create an innovation ecosystem.\ua0The concept of an innovation ecosystem is a powerful analogy to explain value co-creation in\ua0a network. In general, ecosystems are broad cooperative networks, in which the actors coalesce\ua0organically and co-evolve through the construction of a value proposition. Although several\ua0scholars have studied value co-creation in an ecosystem, few have explored the process of\ua0ecosystem emergence. Also, extant research on ecosystem primarily investigates orchestration\ua0capabilities from the perspective of technology firms or new entrants that emerge within an\ua0ecosystem. Few empirical studies investigate how incumbent firms can co-create value and\ua0develop capabilities to orchestrate an ecosystem as a keystone actor.In this context, this thesis investigates a manufacturing firm’s efforts to develop a new\ua0technology. The research was designed as an ethnographic in-depth case study of Volvo Car\ua0Group, an incumbent in the automotive industry. The thesis employs a qualitative abductive\ua0research approach to explore the collaborations related to the development of AD technology,\ua0a discontinuous technological change for incumbent automotive firms. Based on a four-year\ua0longitudinal case study and findings from four papers, the thesis makes important contributions\ua0to scholarly understanding of ecosystem emergence in traditional industries.This thesis makes three main contributions to literature on innovation ecosystems: (1) it\ua0describes ‘layered modularity’ as a design mechanism that facilitates joint value creation\ua0leading to the emergence of an innovation ecosystem, (2) it shows how developing physical\ua0products (such as devices or hardware platforms) and digital systems (such as IoT technologies\ua0or software) in distinct layers allows intertwining of divergent innovation activities anddevelopment methods, (3) it distinguishes between three distinct activities – cooperation,\ua0coordination and competition – that incumbents firms need to manage in order to become a\ua0keystone actor and orchestrate the ecosystem. The findings presented in this thesis have\ua0important implications for manufacturing firms looking to leverage a DTC to create new\ua0ecosystems
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