Dissertations / Theses on the topic 'MQTT protokol'

The aim of this work is to create a unified control and supervision system, SCADA, for controlling the heating and cooling of the company. The system is controlled by UniPi PLC units. Node-RED is used as control software. The user interface is created by an extension "dashboard". For communication between elements using the MQTT protocol. The InfluxDB database is used for data storage. The Grafana tool is used to visualize historical data. The majority of the created system consists of open software. The system is universal, expandable and it is possible to connect it with another system. The system can be used or adapted to similar problems of advanced heating control.

Cílem této práce je vytvořit komunikační sběrnici pro platformu Testos, což umožní nástrojům platformy spolu komunikovat a využívat navzájem svoje služby. V textu jsou prozkoum8na současná řešení a protokoly založené na modelu Publish-Subscribe. Dále také práce specifikuje požadavky na komunikační sběrnici vyhovující potřebám platformy Testos a také navrhuje řešení pro splnění daných požadavků.   V rámci výzkumu byly prozkoumány tři řešení - MQTT, DDS a AMQP. Průzkum každého řešení byl zaměřen na způsob komunikace a hlavní funkční prvky. Jako startovací bod implementace sběrnice byl vybrán protokol MQTT. Tato práce také specifikuje jak tento protokol rozšířit, aby byly splněny požadavky na sběrnici. Mezi stěžejní rozšíření navrhnuté v rámci této práce patří management životního cyklu požadavků rozšiřující způsob doručování zpráv a mechanismus zasílání požadavků standardu MQTT. Protokol byl také rozšířen o možnost shlukování zpráv do BULK paketu za účelem snížení množství potřebných síťových zdrojů. Výsledkem je Testos Bus, který je postavený na upraveném a rozšířeném protokolu MQTT, který zahrunuje implementaci brokeru a klientských knihoven pro Python a C++. Testos Bus naplňuje všechny povinné požadavky platformy, což ověřují automatické testy.

Syftet med denna studie är att undersöka och förstå hur säkerhetsöverträdelser kan förhindrasoch mitigeras i ett MQTT protokoll för att öka den överliggande säkerheten. Jag är särskiltintresserad av tekniker såsom Fuzzing, Fuzzy Logic och Machine Learning..För att undersöka syftet, analyserade och diskuterade jag tidigare implementationer avFuzzing, Fuzzy Logic och Machine Learning, i ett MQTT protokoll. Analysen visade attFuzzing ansågs vara en väldigt effektiv metod för att förhindra säkerhetsöverträdelser samtatt både Fuzzy Logic och Machine Learning var effektiva metoder för mitigering.Sammanfattningsvis, kan säkerhetsnivån i ett MQTT protokoll öka genom implementering avmetoder som används i syfte att förhindra och mitigera säkerhetsöverträdelser. Exempelviskan man först använda Fuzzing för att hitta och korrigera sårbarheter och därigenomförhindra dem. Därefter kan man antingen använda sig av Fuzzy Logic eller MachineLearning för att mitigera plötsliga attacker på MQTT protokollet när den är i produktion.Detta betyder att att utvecklaren kan kombinera metoder för att både förhindra och mitigeraöverträdelser i syfte att öka säkerhetsnivån i ett MQTT protokoll.

Human seeks the maximum profits with least efforts in each and every single life aspect. The development of technology starting with the machine-to-machine concept to reduce human interface with manufacturing processes, hence reducing errors, cost and time. The development enters a new era of connecting those machines and devices to internet, and furthermore make part of data processing and analysis at those machine or devices parts. This concept is what is known nowadays as the Internet of Things (IoT). In this thesis, design for a proposed system is introduced. MQTT messaging protocol used as the data exchange protocol to aggregate the data from WSN that incorporated local and remote sensor. ATmega 328 microcontroller unit, NodeMCU development board, SIM800L GSM module and DHT11 sensor modules where used to implement the nodes while Raspberry Pi 3B was used to implement a gateway that acts as the MQTT broker in order to aggregate the data. The proposed system has been implemented and tested successfully. The power consumption for the remote sensor nodes consumed only 20 mWh and the response time for the data transferred within the system’s network from the remote sensor node to the server is about 7 milliseconds with a total error of 0.11%. The system shows an excellent performance and provide a simple solution to link remote sensors which are out of the gateway’s local network coverage.

Internet of things (IoT) är det överläggande området i denna rapport. IoT är ett väldigt intressant I nuläget och är snabbt växande. IoT kan beskrivas som ett nätverk av kommunicerande enheter som delar information och automatiserar eller försimplar uppgifter och därav ökar effektivitet och säkerhet. Området växer så pass fort att det förväntas vara 24 miljarder anslutna enheter vid år 2050, denna utökning leder i sin tur till ett ökat behov av förståelse för IoT protokollen som hanterar kommunikationen emellan enheterna. Detta för att kunna välja det mest optimala protokollet för ett givet scenario. Detta arbete kommer att välja ett lovande protokoll för undersökning samt evaluering gällande dess prestation berörande fördröjning, dataöverföringshastighet och skalbarhet.  Protokollet som valdes var MQTT (Message Queuing Telemetry Transport). Baserat på dessa evaluerade värden föra en diskussion gällande protokollets lämplighet inom scenariona. Värdena kommer att tas fram via tidmätningar start till slut för kommunikationen samt tid för att skicka en mängd meddelanden, båda i respekt till antalet samtidigt kommunicerande program. Testen körs med en lokal PC som agerar Broker och en Raspberry Pi som kör samtliga programmen i individuella terminaler. Resultaten var att fördröjningen verkar ha en näst intill linjär relation och dataöverföringshastighet ett exponentiellt avtagande beteende i respekt till samtidigt kommunicerande enheter. Dem mätta resultaten analyseras och diskuteras, och kommer till slutsatsen att protokollet är en lämplig kandidat för de flesta scenarion, så som smarta bilar, smarta hem och till viss del industriell användning. Den största nackdelen med protokollet var dess höga standardavvikelse gällande individuella meddelandens fördröjning.<br>Internet of things (IoT) is the base topic of this thesis, and it is a rapidly growing area, it can be described  as a network of communicating devices sharing information and streamlining tasks in addition to increasing efficiency and security. It is expected to be 24 billion connected devices by year 2050 and with this growth comes an increased demand on understanding the IoT protocols to be able to choose a suitable protocol for a given scenario. This thesis will discuss this area and pick one protocol to evaluate specifically regarding latency, throughput, and scalability. The protocol chosen were MQTT (Message Queuing Telemetry Transport). Based on these values then discuss whether the protocol is a suitable candidate for the scenarios. The data to evaluate this will be gathered by measuring the end-to-end time of the protocol in respect to the number of communicating programs, and to measure the time it takes to communicate a number of messages with respect to the number of programs handling the communication. These tests are performed with a local PC acting as the broker and a Raspberry pi running each of the communicating programs on individual terminals. The results were that latency seem to have a close to liner relation, and that throughput seem to have an exponentially decreasing relation with respect to number of clients cooperating. The measured results are analyzed and discussed and concluded that the protocol is a fitting candidate for most scenarios such as smart cars, smart homes and to some extent industry. The biggest flawed concluded was the protocols high standard deviation for individual messages latency. The outcome of the benchmarks measurement showed that increasing the number of nodes would not result in superior performance. It was noted that an optimal number of nodes was found to be between 1 and 20 for all the tests performed. The study showed that no load balancer could be considered a clear winner, instead, different configurations of load balancers performed varyingly well at different tests.

This thesis project has studied a number of protocols that could be used to communicate between a vehicle and a remote server in the context of Scania’s connected services. While there are many factors that are of interest to Scania (such as response time, transmission speed, and amount of data overhead for each message), this thesis will evaluate each protocol in terms of how much data overhead is introduced and how packet loss affects this overhead. The thesis begins by giving an overview of how a number of alternative protocols work and what they offer with regards to Scania’s needs. Next these protocols are compared based on previous studies and each protocol’s specifications to determine which protocol would be the best choice for realizing Scania’s connected services. Finally, a test framework was set up using a virtual environment to simulate different networking conditions. Each of the candidate protocols were deployed in this environment and setup to send sample data. The behaviour of each protocol during these tests served as the basis for the analysis of all of these protocols. The thesis draws the conclusion that to reduce the data transmission overhead between vehicles and Scania’s servers the most suitable protocol is the UDP based MQTT SN.<br>I den här rapporten har jag undersökt ett antal protokoll som kan användas för att kommunicera mellan server och lastbil och därmed användas för Scanias Connected Services. Då det är många faktorer som är intressanta när det kommer till kommunikation mellan lastbil och server för Scania som till exempel responstid, överföringshastighet och mängden extra data vid överföring så har jag valt att begränsa mig till att utvärdera protokollen utifrån hur mycket extra data de använder vid överföring och hur detta påverkas av paketförlust. Rapporten börjar med att ge en överblick över vilka tänkbara protokoll som kan användas och vad de kan erbjuda gällande Scanias behov. Efter det så jämförs protokollen baserat på tidigare studier och protokollens specifikationer för att avgöra vilket protokoll som är bäst lämpat att användas i Scanias Connected Services. Sists så skapas ett virtuellt ramverk för att simulera olike nätverksförhållanden. Här testas varje protokoll och får sända olike datamängder för att sedan få sin prestanda utvärderad baserat på hur mycket extra data som sändes. Dessa resultat ligger sedan till grund för den analys och slutsats angående vilket protokoll som är bäst lämpat att användas av Scania. Rapporten drar slutsatsen att baserat på den information som finns tillgänglig och de resultat som ficks av testerna så skulle den UDP baserade MQTT-SN vara bäst lämpad för att minimera mängden extra data som skickas.

This study compares the scalability of two popular communication protocols within IoT, MQTT and WebSocket. The scalability comparison of the protocols is performed using a publish-subscribe pattern. EMQX is used to run the MQTT message broker, and Socket.IO is used for theWebSocket message broker. Five metrics are recorded; memory usage, network usage, CPU utilization, Round Trip Time (RTT) and message loss. The brokers are set in two different scenarios. The first scenario being many publishers and few subscribers, and the second scenario being many subscribers and few publishers. AWS EC2 is used to host the brokers, as well as the publishers and subscribers. The findings of this study indicate that WebSocket is best suited for memory usage and CPU utilization. MQTT is much better suited when it comes to network usage. MQTT and WebSocket has almost identical average RTT in the first scenario. However in the second scenario MQTT has an average RTT of 164 ms, compared to WebSocket that has an average RTT of 331 ms. Both communication protocols perform similar for message loss, whereWebSocket has zero dropped message, while  MQTT has a drop rate of only 0.001%.<br>Denna studie jämförde skalbarheten mellan två populära kommunikationsprotokoll inom IoT, MQTT och WebSocket. För att jämföra skalbarheten av kommunikationsprotokollen användes en utgivare-prenumerant-metodik. För MQTT användes meddelandehanteraren EMQX, och för WebSocket användes Socket.IO. Fem mätvärden dokumenterades; minnesanvändning, nätverksanvändning, CPU-användning, tur och retur - tid och meddelandeförlust. Meddelandehanterarna sattes i två olika scenarier. Första scenariot bestod av många utgivare och få prenumeranter. Det andra scenariot bestod av många prenumeranter och få utgivare. AWS EC2 användes för att agera som värd för meddelandehanterarna, samt för utgivarna och prenumeranterna. Resultaten av denna studie indikerar att WebSocket är bäst lämpad för minnesanvändning och CPU-användning. MQTT är däremot bättre lämpad för nätverksanvändning. MQTT och WebSocket hade nästan identiska genomsnittliga tur och retur - tider i första scenariot, dock i andra scenariot hade MQTT en genomsnittlig tur och retur - tid på 164 ms medan WebSocket hade en genomsnittlig tur och retur - tid på 331 ms. Båda kommunikationsprotokollen hade snarlika resultat när det kom till  meddelandeförlust, WebSocket hade noll tappade meddelanden och MQTT hade en meddelandeförlust på 0.001 %.

In this thesis we investigated the MQTT protocol, which results in being a valid solution for data transmission in an IoT solution. After having explored the main communication protocols, we focused on the main features of the MQTT that has been selected for our application. To this purpose, a MQTT broker has been created on Node-RED, while the remaining elements of the application have been developed on MATLAB. In particular, we exploited the MQTT and the Database toolboxes: the former is used to exchange data between two PCs through the MQTT protocol, while the latter is necessary to insert data into a database. Before describing the application, we discussed the relevance of databases and the one we have chosen for our need. The application we implemented showed how to transmit smart data between different devices on the same network through the MQTT protocol, with the aim to store information in a central database on PostgreSQL. The architecture built could be easily generalized and therefore applied in a real industrial case, as the possibility to centralize data generated from several machine controllers is becoming a fundamental requirement for industries. In summary, the aim of this paper is to create a new communication exchange information data between machines in an industry, home or any other domain by using the lightweight protocol communication call MQTT. Although Node-Red, MatLAb, Postgres can be written in different program language, they can share each other information, data to manage, control and monitoring entire system without using any cable to link the machine but only an Internet connection. IIoT becomes more popular nowadays.

La transformación digital ha traído consigo muchos beneficios y retos para las empresas; y pese a ello, aún se tiene muchos inconvenientes en adoptar un sistema centralizado para las tecnologías IoT. Las plataformas IoT son sistemas solicitados por las empresas para unificar toda la labor de gestión y operativa relativa al IoT, sin embargo, las empresas para optar por un nuevo tipo de tecnología requieren de referencias de mercado como evaluaciones en ambientes de prueba, diseños validados o experiencias en la misma tecnología en otras empresas del mismo rubro. A pesar de esto, se carece de estas pruebas, evaluaciones y estándares en las plataformas IoT actuales del mercado por lo cual se dificulta su adopción. Es así, como la presente tesis tiene como objetivo realizar la prueba, evaluación y diseño del rendimiento de una plataforma IoT empleando software de código libre. Esto se realizará mediante la implementación de todos los componentes en un centro de datos de prueba y como resultado, se podrá contrastar el beneficio de las distintas plataformas IoT en cada escenario establecido. Dado que los escenarios propuestos son en base a plataformas IoT de terceros, se busca desarrollar un nuevo sistema que cubra las mismas capacidades, y por consiguiente, sea el inicio de futuros proyectos que se complementen con lo propuesto para las tecnologías IoT Finalmente, obtenido toda la información y capacidades respecto a las plataformas, se realizó un análisis exhaustivo del porqué de cada parámetro recibido y como estos pueden beneficiar a los requerimientos empresariales de todo tamaño. Como resultado final, se propone un estudio de mercado en el cual la empresa analizara los costos de implementación para un tipo de escenario.

Many industries are now moving several of their processes into the cloud computing sphere. One important process is to collect machine data in an effective way. Moving signal collection processes to the cloud instead of on premise raises many questions about performance, scalability, security and cost.This thesis focuses on some of the market leading and cutting edge protocols appropriate for industrial production data collection. It investigates and compares the pros and cons of the protocols with respect to the demands of industrial systems. The thesis also presents examples of how the protocols can be used to collect data all the way to a higher-level system such as ERP or MES.The protocols focused on are MQTT and AMQP (in OPC-UA). The possibilities of OPC-UA in cloud computing is of extra interest to investigate in this thesis due to its increasing usage and development.

A current challenge in the Internet of Things is the seeking after conceptual structures to connect the presumably billions of devices of innumerable forms and capabilities. An emerging architectural concept, the fog cloud computing, moves the seemingly unlimited computational power of the distant cloud to the edge of the network, closer to the potentially computationally limited things, effectively diminishing the experienced latency. To allow computationally-constrained devices partaking in the network they have to be relieved from the burden of constant availability and extensive computational execution. Establishing a publish/subscribe communication pattern with the utilization of the popular Internet of Things application layer protocol Constrained Application Protocol is depicted one approach of overcoming this issue. In this project, a Java based library to establish a publish/subscribe communication pattern for the Constrained Application Protocol was develop. Furthermore, efforts to build and assess prototypes of several publish/subscribe application layer protocols executed over varying common as well as secured versions of the standard and non-standard transport layer protocols were made to take advantage, evaluate, and compare the developed library. The results indicate that the standard protocol stacks represent solid candidates yet one non-standard protocol stack is the considered prime candidate which still maintains a low response time while not adding a significant amount of communication overhead.

Le aziende manufatturiere affrontano costantemente problemi di ottimizzazione dei processi di logistica per cercare di ottenere sempre di più dalle loro macchine e dai loro processi produttivi utilizzando la tecnologia disponibile. Uno di questi problemi di ottimizzazione `e sicuramente la logistica per la gestione del magazzino, quindi come utilizzare lo spazio del magazzino efficientemente e allo stesso tempo ottenere l’instradamento ottimo dei veicoli che trasportano i prodotti nelle varie fasi di lavorazione. L’obiettivo di questa tesi `e di cercare i diversi approcci usati in letteratura e sulla base di questi migliorare il routing delle macchine e l’assegnazione delle risorse in uno scenario reale. Un algoritmo di routing `e stato modificato e migliorato per il caso specifico con una euristica di assegnazione delle risorse che meglio gestisce l’uso del magazzino e dei veicoli. In aggiunta a ci`o sono stati analizzati diversi metodi di comunicazione fra l’algoritmo e il software di simulazione usato per il testing. In particolare diversi protocolli per comunicazione macchina-macchina sono stati esaminati per vedere quale sarebbe la scelta migliore una volta che il software sar`a implementato in un ambiente di produzione reale.

The Internet of Things market grows at an extreme rate each passing year. Devices will gather more data, which puts a lot of pressure on the communication between the devices and the cloud. The protocols used needs to be fast, secure, reliable and send any type of content. This thesis work conducts a research of the three most popular application level protocols ; MQTT, HTTP and AMQP, to examine which is best suited in an Internet of Things environment. The project is made with Axians AB to provide insight regarding the protocols, so that the company can decide which protocol will be best suited for their projects. A theoretical study of the performance was made, followed by case studies on different aspects of the protocol. The case studies were made using a Dell gateway and a 4G connection to mimic a real world project. Scripts were developed to measure different performance attributes of the protocols. The analysis and discussion of the results proved that MQTT or AMQP is the best protocols, depending on the project.

Internet of Things, or the infrastructure of the information age society, is an expanding area of research. It is the idea that physical things that we have today, can be turned into devices by being connected to a network. The purpose of these devices is through more sensors and actuators, allow smarter and more robust infrastructure to be built, as well as improving consumer devices interoperability. This thesis will investigate the current state of the art application layer communication protocols that have been developed with resource constrained mobile devices in mind. It will look specifically at high latency mid-range wireless cellular communication by investigating how the protocols affect energy consumption for an embedded Internet of Things device. This is done with the constraint that these findings needs to be applicable to the fifth generation of cellular networks, as well as extensions to current generation standards. The application layer communication protocols Constrained Applications Protocol(CoAP), Message Queue Telemetry Transport(MQTT) and Hypertext Transfer Protocol(HTTP) used on multiple modem modules, are investigated in a quantitative approach in deductive survey experiments, testing a variety of what is concluded to be typical sensor and actuator scenarios. The goal with the survey, is to ultimately select the protocol that shows to be the most suitable for a project to build a prototype platform for embedded mobile devices in the shape of publicly shared bikes in a city. This prototype is described and its architecture and design decisions are presented and argued for. The survey discovers that CoAP is the most suitable protocol for the purpose of the thesis, and proceeds to show how it is applied to the described platform.

The IoT refers to the idea of internetworking physical devices, vehicles, buildings, and any other item embedded with the appropriate electronics, software, sensors, actuators, and network connectivity to allows them to interchange data and to provide highly effective new services. In this thesis we focus on the communications issues of the IoT in relation to mobility and we provide different solutions to alleviate the impact of these potential problems and to guarantee the information delivery in mobile scenarios. Our reference context is a Smart City where various mobile devices collaboratively participate, periodically sending information from their sensors. We assume that these services are located in platforms based in cloud infrastructures where the information is protected through the use of virtualisation ensuring their security and privacy. This thesis is structured into seven chapters. We first detail our objectives and identify the current problems we intend to address. Next, we provide a thorough review of the state of the art of all the areas involved in our work, highlighting how we improved the existing solutions with our research. The overall approach of the solutions we propose in this thesis use prototypes that encompasses and integrates different technologies and standards in a small infrastructure, using real devices in real scenarios with two of the most commonly used networks around the world: WiFi and 802.15.4 to efficiently solve the problems we originally identified. We focussed on protocols based on a producer/consumer paradigm, namely AMQP and particularly MQTT. We observed the behaviour of these protocols using in lab experiments and in external environments, using a mesh wireless network as the backbone network. Various issues raised by mobility were taken into consideration, and thus, we repeated the tests with different messages sizes and different inter-message periodicity, in order to model different possible applications. We also present a model for dimensioning the number of sources for mobile nodes and calculating the number of buffers required in the mobile node as a function of the number of sources and the size of the messages. We included a mechanism for avoiding data loss based on intermediate buffering adapted to the MQTT protocol that, in conjunction with the use of an alternative to the Network Manager in certain contexts, improves the connection establishment for wireless mobile clients. We also performed a detailed study of the jitter behaviour of a mobile node when transmitting messages with this proposal while moving through a real outdoor scenario. To emulate simple IoT networks we used the Cooja simulator to study and determine the effects on the probability of delivering messages when both publishers and subscribers were added to different scenarios. Finally we present an approach that combines the MQTT protocol with DTN which we specifically designed for constrained environments and guarantees that important information will never be lost. The advantage of our proposed solutions is that they make an IoT system more resilient to changes in the point of attachment of the mobile devices in an IoT network without requiring IoT application & service developers to explicitly consider this issue. Moreover, our solutions do not require additional support from the network through protocols such as MobileIP or LISP. We close the thesis by providing some conclusions, and identifying future lines of work which we unable to address here.<br>Internet de las cosas (IoT) se refiere a la idea de interconectar sensores, actuadores, dispositivos físicos, vehículos, edificios y cualquier elemento dotado de la electrónica, así como del software y de la conectividad de red que los hace capaces de intercambiar datos para proporcionar servicios altamente efectivos. En esta tesis nos centramos en temas relacionados con la comunicación de sistemas IoT, específicamente en situaciones de movilidad y en los problemas que esto conlleva. Con este fin ofrecemos diferentes soluciones que alivian su impacto y garantizan la entrega de información en estas situaciones. El contexto de referencia es una ciudad inteligente donde varios dispositivos móviles participan de forma colaborativa enviando periódicamente información desde sus sensores hacia servicios ubicados en plataformas en la nube (cloud computing) donde mediante el uso de virtualización, la información está protegida garantizando su seguridad y privacidad. Las soluciones propuestas en esta tesis se enfocan en probar sobre una pequeña infraestructura un prototipo que abarca e integra diferentes tecnologías y estándares para resolver eficientemente los problemas previamente identificados. Hemos enfocado nuestro esfuerzo en el uso de dispositivos sobre escenarios reales con dos de las redes más extendidas en todo el mundo: WiFi y enlaces 802.15.4. Nos enfocamos en protocolos que ofrecen el paradigma productor/consumidor como el protocolo avanzado de colas de mensajes (AMQP) y particularmente el protocolo de transporte de mensajes telemétricos (MQTT), observamos su comportamiento a través de experimentos en laboratorio y en pruebas al aire libre, repitiendo las pruebas con diferentes tamaños de mensajes y diferente periodicidad entre mensajes. Para modelar las diferentes posibles aplicaciones de la propuesta, se tomaron en consideración varias cuestiones planteadas por la movilidad, resultando en un modelo para dimensionar eficientemente el número de fuentes para un nodo móvil y para calcular el tamaño requerido del buffer, en función del número de fuentes y del tamaño de los mensajes. Proponemos un mecanismo adaptado al protocolo MQTT que evita la pérdida de datos en clientes móviles, basado en un buffer intermedio entre la producción y publicación de mensajes que, en conjunto con el uso de una alternativa al gestor de conexiones inalámbricas "Network Manager", en ciertos contextos mejora el establecimiento de las conexiones. Para la evaluación de esta propuesta se presenta un estudio detallado de un nodo móvil que se mueve en un escenario real al aire libre, donde estudiamos el comportamiento del jitter y la transmisión de mensajes. Además, hemos utilizado emuladores de redes IoT para estudiar y determinar los efectos sobre la probabilidad de entrega de mensajes, cuando se agregan tanto publicadores como suscriptores a diferentes escenarios. Finalmente, se presenta una solución totalmente orientada a entornos con dispositivos de recursos limitados que combina los protocolos MQTT con redes tolerantes a retardos (DTN) para garantizar la entrega de información. La ventaja de las soluciones que proponemos reside en el hecho de que los sistemas IoT se vuelven resilientes a la movilidad y a los cambios de punto de acceso, permitiendo así que los desarrolladores creen fácilmente aplicaciones y servicios IoT evitando considerar estos problema. Otra ventaja de nuestras soluciones es que no necesitan soporte adicional de la red como sucede con protocolos como MobileIP o el protocolo que separa el identificador del localizador (LISP). Se destaca cómo hemos mejorado las soluciones existentes hasta el momento de la escritura de esta disertación, y se identifican futuras líneas de actuación que no han sido contempladas.<br>Internet de les coses (IoT) es refereix a la idea d'interconnectar sensors, actuadors, dispositius físics, vehicles, edificis i qualsevol element dotat de l'electrònica, així com del programari i de la connectivitat de xarxa que els fa capaces d'intercanviar dades per proporcionar serveis altament efectius. En aquesta tesi ens centrem en temes relacionats amb la comunicació de sistemes IoT, específicament en situacions de mobilitat i en els problemes que això comporta. A aquest efecte oferim diferents solucions que alleugeren el seu impacte i garanteixen el lliurament d'informació en aquestes situacions. El context de referència és una ciutat intel·ligent on diversos dispositius mòbils participen de forma col·laborativa enviant periòdicament informació des dels seus sensors cap a serveis situats en plataformes en el núvol (cloud computing) on mitjançant l'ús de virtualització, la informació està protegida garantint la seva seguretat i privadesa. Les solucions proposades en aquesta tesi s'enfoquen a provar sobre una xicoteta infraestructura un prototip que abasta i integra diferents tecnologies i estàndards per a resoldre eficientment els problemes prèviament identificats. Hem enfocat el nostre esforç en l'ús de dispositius sobre escenaris reals amb dos de les xarxes més esteses a tot el món: WiFi i enllaços 802.15.4. Ens enfoquem en protocols que ofereixen el paradigma productor/consumidor com el protocol avançat de cues de missatges (AMQP) i particularment el protocol de transport de missatges telemètrics (MQTT), observem el seu comportament a través d'experiments en laboratori i en proves a l'aire lliure, repetint les proves amb diferents grandàries de missatges i diferent periodicitat entre missatges. Per a modelar les diferents possibles aplicacions de la proposta, es van prendre en consideració diverses qüestions plantejades per la mobilitat, resultant en un model per a dimensionar eficientment el nombre de fonts per a un node mòbil i per a calcular la grandària requerida del buffer, en funció del nombre de fonts i de la grandària dels missatges. Proposem un mecanisme adaptat al protocol MQTT que evita la pèrdua de dades per a clients mòbils, basat en un buffer intermedi entre la producció i publicació de missatges que en conjunt amb l'ús d'una alternativa al gestor de connexions sense fils "Network Manager'', en certs contextos millora l'establiment de les connexions. Per a l'avaluació d'aquesta proposta es presenta un estudi detallat d'un node mòbil que es mou en un escenari real a l'aire lliure, on estudiem el comportament del jitter i la transmissió de missatges. A més, hem utilitzat emuladors de xarxes IoT per a estudiar i determinar els efectes sobre la probabilitat de lliurament de missatges, quan s'agreguen tant publicadors com subscriptors a diferents escenaris. Finalment, es presenta una solució totalment orientada a entorns amb dispositius de recursos limitats que combina els protocols MQTT amb xarxes tolerants a retards (DTN) per a garantir el lliurament d'informació. L'avantatge de les solucions que proposem resideix en el fet que els sistemes IoT es tornen resilients a la mobilitat i als canvis de punt d'accés, permetent així que els desenvolupadors creuen fàcilment aplicacions i serveis IoT evitant considerar aquests problema. Un altre avantatge de les nostres solucions és que no necessiten suport addicional de la xarxa com succeeix amb protocols com MobileIP o el protocol que separa l'identificador del localitzador (LISP). Es destaca com hem millorat les solucions existents fins al moment de l'escriptura d'aquesta dissertació, i s'identifican futures línies d'actuació que no han sigut contemplades.<br>Luzuriaga Quichimbo, JE. (2017). Managing Mobility for Distributed Smart Cities Services [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/84744<br>TESIS

碩士<br>醒吾科技大學<br>資訊科技應用系<br>107<br>The present paper proposed a set utilizes Wi-Fi and the MQTT communication agreement design intelligence networking, may use on the general table the computer, the motion type writes down the homepage browsing function which the computer homepage browser as well as the plate computer, the wisdom handset already have, holds controls the general family common electric appliance equipment, for example: In the electric lamp, the big door lock, the garage gate, the air conditioner and the room the temperature difference control and so on, achieves establishing of the immediate control system.This research uses the wisdom handset Android system and Node MCU ESP8266 the Wi-Fi mold train took the control device, and take the VirtualBox-5.1.28 version as the work system, uses Hostinger web server and the Drupal composition homepage formula, 2 develops motion application formula APP by App Inventor.And unifies the MQTT communication agreement and Node MCU ESP8266 the Wi-Fi mold train, when in control electric appliance equipment, no matter the body in where all, can immediate knowing the electrical equipment do at present moves the condition. In addition, does the high in the clouds let Web the Server installment and the hypothesis no longer is a puzzle, whether the examination holds controls when APP and Web Server has the synchronization to do moves, in the function anticipated achieves holds controls as well as the homepage browser immediate control system, and application of the realization intelligence networking correlation technology.

碩士<br>國立聯合大學<br>資訊工程學系碩士班<br>107<br>Recently, the applications of Internet of Things technique are widely used in our life. The Internet of Things is considered as a technique using Internet. Several new and innovative lifestyles have been created and IoT becomes an indispensable part in human lives. Human can remotely control all devices using Internet at any time without location limitation. The data are collected, shared and analyzed for improving the life quality. In this thesis, we have designed a platform for providing IoT services using in a smart home. It is a low-cost and scalable network by integrating the wireless communication and cloud network for IoT services. Any new sensor or device can easily be mounted and connects with the platform using wireless networks. The MQTT protocol is adopted for high efficiency consideration. The designed platform is easily installed because of the user-friendly interfaces. Users can remotely control any devices at home using the web-browsers without any software installation. We can browse the data from any devices such as PCs, smart phones, tablets, laptops, etc. The data of sensors are continuously collected and stored at a specified storage device. The environment is monitored by several simple rules from the collected sensor data. They will be retrieved and analyzed in the future. In addition, a start mirror is also designed for device control and data access. Personal data such e-mail, calendar, weather report are displayed on the mirror when people standard at the front of mirror. People are identified by using face recognition. Machine learning techniques are integrated into the face recognition module. Each captured face image are learned and re-trained for accuracy improvement. The audio function for reading news is also provided. Using this smart mirror, people can access and control all devices in a smart home.

碩士<br>國立臺灣科技大學<br>資訊管理系<br>105<br>With the rapid advancements in Internet of Things (IoT), there are a lot of sensors deployed in each environment such as home, hospitals, and factories. By using these sensors, we can collect different kinds of data from the environment and analyze it later. However, these sensors which have functionality to connect Internet have become attacked targets by malicious hacker. Although the manufacturers release new version of firmware to resolve vulnerability for specific sensors, the administrator of sensors may ignore the importance of firmware update. As a result, sensors are still under threat of attacks. Nevertheless, the firmware update mechanism for sensors is not perfect nowadays. We must assure that a reliable method to verify the integrity and provider of firmware. Otherwise, if sensors install malicious firmware, they will be out of order or controlled by attackers to launch attacks in the future. To sum up, this thesis designs a secure IoT firmware update mechanism based on Message Queuing Telemetry Transport(MQTT) protocol. It assures that new version of firmware provided by manufacturers can be pushed to corresponding sensors efficiently. We use Elliptic Curve Diffie-Hellman Key Exchange(ECDH), Digital Signature, and Keyed-hash Message Authentication Code(HMAC) algorithms in the protocol to accomplish machine-to-machine authentication. If firmware is modified or provided by attackers, our proposed protocol will detect it. Consequently, we promise that malicious firmware won’t be installed on sensors. Finally, we adopt a security analysis for our protocol, and confirm that our proposed protocol can defend common attacks such as Eavesdropping Attack, Man-in-the-middle Attack, Replay Attack, and Impersonation Attack.

碩士<br>真理大學<br>資訊工程學系碩士班<br>106<br>Internet of Tings (IoT) attracts a lots of attention recently. Since IoT is the underlying technology of applications such as smart city, wearable technology, and Industry 4.0, the number of IoT devices is rapidly increasing. For these applications, IoT devices will send secure sensitive data to cloud or other IoT devices for further processing through network protocol, such as Message Queue Telemetry Transport (MQTT). Since data is transmitted over Internet, attackers can easily obtain data by sniffing networks. Therefore, MQTT supports Transport Layer Security (TLS) and Access Control List (ACL) to protect data. Unfortunately, MQTT-TLS provides session encryption only and the data can be exposed at broker. On the other hand, the performance of MQTT-ACL can be enormously decreased with the increasing number of ACL rules for massive IoT devices. For solving these problems, we design and implement MQTT Thing-to-Thing Security protocol (MQTT-TTS). MQTT-TTS provides end-to-end security which prevents data leak at broker. Since IoT devices are typically resource constrained, MQTT-TTS supports multiple security algorithms which can be selected according to the capabilities of IoT devices. Moreover, data sharing is essential for most of IoT applications but is difficult if the data is encrypted with traditional encryption systems. Thus, MQTT-TTS supports Ciphertext-Policy Attribute Based Encryption (CP-ABE) which provides flexible and fine grained access control. In order to evaluate the performance of MQTT-TTS, MQTT-TTS with CP-ABE is implemented on personal computer (PC) and Raspberry Pi 3 (RPi). According to the experimental results, MQTT-TTS with CP-ABE will not consume much resources in resource-rich PC. However, for RPi, the performance can be obviously degraded if the complexity of access policy of CP-ABE becomes higher. Thus, we conclude several suggestions to apply MQTT-TTS with CP-ABE to resource-constrained IoT devices based on our experimental results. Moreover, a delegation approach is also proposed to improve the performance of MQTT-TTS with CP-ABE. The proposed delegation approach can improve the performance of MQTT-TTS with CP-ABE by 40~80% under the premise of keeping data privacy.

碩士<br>健行科技大學<br>電子工程系碩士班<br>103<br>In recent years, disasters such as fire and gas explosion were frequently reported by TV news, the Internet and other media. Most of these disasters were caused by human negligence. If more attention was paid on early signs of these disasters, they are not inevitable. In this paper, we propose a cloud environment monitoring system based on internet MQTT communication protocol. The objective is to monitor the environment, access the environmental information by sensors. If a precursor of a disaster is determined (or a disaster has occurred), the information will be immediately broadcasted via the Internet to the relevant personnel to exclude the disaster. Our study is implemented on Raspberry Pi platform. A variety of environmental sensors transmit information to the Raspberry Pi platform. Based on the MQTT protocol, the values of sensors can be transmitted to the Server for analysis and the result will be broadcasted via the Internet to the end users.

碩士<br>醒吾科技大學<br>資訊科技應用系<br>105<br>By the incoming of the IoT (Internet of Things) era, scholars design it aimed at various communication protocols. Recently, the development of MQTT has become an appropriate technique applied on IoT due to its simple, stable output and low cost. Hence, “combined WIFI model and MQTT communication protocol’s encrypted system” is used to integrate smartphones and computer with the MQTT theory in order to achieve instant web page control and monitor system. For example, controlled television, air conditioner, and access card etc. To eventually fulfill home automated IoT. In this research, the controller device is based on the integration between smartphone’s WIFI and internet function and computer’s web browser. The micro-processor device is based on NodeMCU ESP8266’s WIFI model. Finally, the web page and code is written by ESPlorer operating system and the APP on smartphones is written by using App Inventor 2. Furthermore, information conveyed within can be stabilized and encrypted by combining the MQTT communication protocol onto WIFI model using AES-128 bits. Via results of examining the system pressing on/off through different environments and distances, the reacting time is 5 seconds, which is in reasonable range. In addition, tests of monitor, intermediate, and resending charges have been verified. Functions can be controlled without changing fundamental structure, making the communication of IoT a much safer platform.

碩士<br>國立成功大學<br>工程科學系碩士在職專班<br>106<br>The technology of the internet of things(IoT) has be widely used in our life, and the internet communication protocols included is not only Http/Https, but also other new ones such as xmpp, coap, and mqtt. The requirements of internet of things(IoT) is that network communication jobs can work normally even in low-quality signal environments, and mqtt is recognized as one of the suitable protocol for message notification applications. Generally, as the number of external sensing devices increase, the number of connections also increase, and the pressure on the server will also increase. In order to receive instant alarm messages from the server broker, clients must keep connected to the server broker all the time. Both payloads from external devices and clients make it difficult for a single server to handle the large amount of messages, unless clustered servers are available. However, currently the mqtt-broker software suite that supports clustered server are either unsuitable or too expensive for small companies. The research builds a message notification system based on the mqtt protocol that, by using docker container, supports multiple mqtt broker containers. A mqtt-broker, by using the registry database and the mosquitto_auth_plugin, authenticates an external device and its ACL authorization when it tries to establish a connection to the mqtt-broker. Verified clients will receive from the specific mqtt-broker its related messages retransmitted from the re-transmitters. Results show the system can indeed transfer messages across mqtt brokers to their destinations. It achieves the purpose of clustering mqtt brokers that can manage connections from clients and dispatch messages to them efficiently.

碩士<br>國立虎尾科技大學<br>光電工程系光電與材料科技碩士班<br>106<br>This thesis realizes a combination of the mobile phone APP and vehicle environmental condition monitoring, uses MQTT protocol to transmit data and implement the mobile phone APP broadcasting function. The system provides three main parts including environmental monitoring, vehicle accident notification, and vehicle locking monitoring. In the environmental monitoring, the system first collects the internal information of the car through sensors that including the temperature, humidity, dangerous gas, vehicle speed, and the location of the vehicle. Afterward, the system uploads the internal information to the cloud storage. In the accident notification, the system will automatically detect and send data to the mobile phone APP through the MQTT if the collision of the vehicle occurred. Besides, the mobile phone APP will generate push notifications to inform the outside world. In addition to informing the car about accidents, the push notification also includes the location of the car in order to reduce the waiting time for rescue. In the vehicle lock monitoring warning, after driving off, you can use the mobile phone APP to transmit data to the system through MQTT to open the door monitoring alert. If the door is opening, the system will transfer data to the mobile phone APP via MQTT. At the same time, the Push notifications will be generated to inform drivers and driver families.

碩士<br>國立交通大學<br>網路工程研究所<br>103<br>In recent years, with the advance of IC design and manufacturing technology, the usage of embedded systems has boosted up. There are many different brands of embedded system boards. The functions of nowadays embedded boards are much powerful and the cost are affordable. As a consequence, Internet of Things (IoT) has achieved a very quick development. IoT sensors required embedded board to read the data which is then sent to Internet or cloud servers. However, the hardware configuration by different manufacturers of embedded boards are different, hence it is hard to setup a one-fit-all IoT platform. In this thesis, we tried to develope a plug and play system with a generic interface to automatically detect and read the sensors. A user only needs to connect the sensors to the plug and play system to run the application. Without human configuration, the data of the sensor can be read, and then the data can be published to the Internet via any kinds of embedded boards. For data transport, we used a lightweight protocol in application layer of Internet. The packet size of this protocol is much smaller and it can reduce the latency and power consumption. Therefore, we can increase the transmission throughput and the utilization of embedded boards. MQTT protocol is using Publish/Subscribe Topic based mechanism. We designed a hierarchical topic name to handle the data from different embedded boards and the plug and play system.

碩士<br>國立成功大學<br>製造資訊與系統研究所<br>106<br>Countries are committed to innovation and transformation of industrial technology for improving the economic growth rate, hence smart factory is widely discussed. For upgrading equipments in a factory from automation to intelligent automation, it is necessary to integrate hardware and intelligent software technology by obtaining various information of the equipment, such as sensing, motion, and actuation, and then analyzing and computing them with the information of production line. The architecture of Industrial Internet of Things (IIoT) will be imported into the device including sensor, actuator, machine controller, cloud computing server in a factory. Each device needs to exchange information with other device and apply to big data analysis. Therefore, the unified information format and communication protocol are more important. A bi-direction manufacturing Information interactive system for factory developed in this thesis lays emphasis on the design of communication architecture. It achieves the communication of machine to IoT device and machine to machine by importing the open protocol－MQTT into the factory and equipping IIoT gateway developed through the embedded system with the machine to collect and filter sensing data and control information. An Android platform offer personnel in the factory to get the necessary information of the machine conveniently and quickly. The mode of publish/subscribe from MQTT is adopted in this platform to realize information delivery service. The system can apply to information delivery, lightweight control, alarm notification, and so on. It can achieve bi-direction information exchange between machine to machine and human to machine.