Performance Evaluation of Class A LoRa Communications

Recently, Low Power Wide Area Networks (LPWANs) have attracted a great interest due to the need of connecting more and more devices to the so-called Internet of Things (IoT). This thesis explores LoRa’s suitability and performance within this paradigm, through a theoretical approach as well as through practical data acquired in multiple field campaigns. First, a performance evaluation model of LoRa class A devices is proposed. The model is meant to characterize the performance of LoRa’s Uplink communications where both physical layer (PHY) and medium access control (MAC) are taken into account. By admitting a uniform spatial distribution of the devices, the performance characterization of the PHY-layer is studied through the derivation of the probability of successfully decoding multiple frames that were transmitted with the same spreading factor and at the same time. The MAC performance is evaluated by admitting that the inter-arrival time of the frames generated by each LoRa device is exponentially distributed. A typical LoRaWAN operating scenario is considered, where the transmissions of LoRa Class A devices suffer path-loss, shadowing and Rayleigh fading. Numerical results obtained with the modeling methodology are compared with simulation results, and the validation of the proposed model is discussed for different levels of traffic load and PHY-layer conditions. Due to the possibility of capturing multiple frames simultaneously, the maximum achievable performance of the PHY/MAC LoRa scheme according to the signal-to-interference-plus-noise ratio (SINR) is considered. The contribution of this model is primarily focused on studying the average number of successfully received LoRa frames, which establishes a performance upper bound due to the optimal capture condition considered in the PHY-layer. In the second stage of this work a practical LoRa point-to-point network was deployed to characterize LoRa’s performance in a practical way. Performance was assessed through data collected in the course of several experiments, positioning the transmitter in diverse locations and environments. This work reports statistics of the received packets and different metrics gathered from the physical-layer

Apport de la Qualité de l’Expérience dans l’optimisation de services multimédia : application à la diffusion de la vidéo et à la VoIP

The emerging and fast growth of multimedia services have created new challenges for network service providers in order to guarantee the best user's Quality of Experience (QoE) in diverse networks with distinctive access technologies. Usually, various methods and techniques are used to predict the user satisfaction level by studying the combined impact of numerous factors. In this thesis, we consider two important multimedia services to evaluate the user perception, which are: video streaming service, and VoIP. This study investigates user's QoE that follows three directions: (1) methodologies for subjective QoE assessment of video services, (2) regulating user's QoE using video a rate adaptive algorithm, and (3) QoE-based power efficient resource allocation methods for Long Term Evaluation-Advanced (LTE-A) for VoIP. Initially, we describe two subjective methods to collect the dataset for assessing the user's QoE. The subjectively collected dataset is used to investigate the influence of different parameters (e.g. QoS, video types, user profile, etc.) on user satisfaction while using the video services. Later, we propose a client-based HTTP rate adaptive video streaming algorithm over TCP protocol to regulate the user's QoE. The proposed method considers three Quality of Service (QoS) parameters that govern the user perception, which are: Bandwidth, Buffer, and dropped Frame rate (BBF). The BBF method dynamically selects the suitable video quality according to network conditions and user's device properties. Lastly, we propose a QoE driven downlink scheduling method, i.e. QoE Power Escient Method (QEPEM) for LTE-A. It esciently allocates the radio resources, and optimizes the use of User Equipment (UE) power utilizing the Discontinuous Reception (DRX) method in LTE-AL'émergence et la croissance rapide des services multimédia dans les réseaux IP ont créé de nouveaux défis pour les fournisseurs de services réseau, qui, au-delà de la Qualité de Service (QoS) issue des paramètres techniques de leur réseau, doivent aussi garantir la meilleure qualité de perception utilisateur (Quality of Experience, QoE) dans des réseaux variés avec différentes technologies d'accès. Habituellement, différentes méthodes et techniques sont utilisées pour prédire le niveau de satisfaction de l'utilisateur, en analysant l'effet combiné de multiples facteurs. Dans cette thèse, nous nous intéressons à la commande du réseau en intégrant à la fois des aspects qualitatifs (perception du niveau de satisfaction de l'usager) et quantitatifs (mesure de paramètres réseau) dans l'objectif de développer des mécanismes capables, à la fois, de s'adapter à la variabilité des mesures collectées et d'améliorer la qualité de perception. Pour ce faire, nous avons étudié le cas de deux services multimédia populaires, qui sont : le streaming vidéo, et la voix sur IP (VoIP). Nous investiguons la QoE utilisateur de ces services selon trois aspects : (1) les méthodologies d'évaluation subjective de la QoE, dans le cadre d'un service vidéo, (2) les techniques d'adaptation de flux vidéo pour garantir un certain niveau de QoE, et (3) les méthodes d'allocation de ressource, tenant compte de la QoE tout en économisant l'énergie, dans le cadre d'un service de VoIP (LTE-A). Nous présentons d'abord deux méthodes pour récolter des jeux de données relatifs à la QoE. Nous utilisons ensuite ces jeux de données (issus des campagnes d'évaluation subjective que nous avons menées) pour comprendre l'influence de différents paramètres (réseau, terminal, profil utilisateur) sur la perception d'un utilisateur d'un service vidéo. Nous proposons ensuite un algorithme de streaming vidéo adaptatif, implémenté dans un client HTTP, et dont le but est d'assurer un certain niveau de QoE et le comparons à l'état de l'art. Notre algorithme tient compte de trois paramètres de QoS (bande passante, taille de mémoires tampons de réception et taux de pertes de paquets) et sélectionne dynamiquement la qualité vidéo appropriée en fonction des conditions du réseau et des propriétés du terminal de l'utilisateur. Enfin, nous proposons QEPEM (QoE Power Efficient Method), un algorithme d'ordonnancement basé sur la QoE, dans le cadre d'un réseau sans fil LTE, en nous intéressant à une allocation dynamique des ressources radio en tenant compte de la consommation énergétiqu

MMBnet 2017 - Proceedings of the 9th GI/ITG Workshop „Leistungs-, Verlässlichkeits- und Zuverlässigkeitsbewertung von Kommunikationsnetzen und Verteilten Systemen“

Nowadays, mathematical methods of systems and network monitoring, modeling, simulation, and performance, dependability and reliability analysis constitute the foundation of quantitative evaluation methods with regard to software-defined next-generation networks and advanced cloud computing systems. Considering the application of the underlying methodologies in engineering practice, these sophisticated techniques provide the basis in many different areas. The GI/ITG Technical Committee “Measurement, Modelling and Evaluation of Computing Systems“ (MMB) and its members have investigated corresponding research topics and initiated a series of MMB conferences and workshops over the last decades. Its 9th GI/ITG Workshop MMBnet 2017 „Leistungs-, Verlässlichkeits- und Zuverlässigkeitsbewertung von Kommunikationsnetzen und Verteilten Systemen“ was held at Hamburg University of Technology (TUHH), Germany, on September 14, 2017. The proceedings of MMBnet 2017 summarize the contributions of one invited talk and four contributed papers of young researchers. They deal with current research issues in next-generation networks, IP-based real-time communication systems, and new application architectures and intend to stimulate the reader‘s future research in these vital areas of modern information society

Systematic Approaches for Telemedicine and Data Coordination for COVID-19 in Baja California, Mexico

Conference proceedings info: ICICT 2023: 2023 The 6th International Conference on Information and Computer Technologies Raleigh, HI, United States, March 24-26, 2023 Pages 529-542We provide a model for systematic implementation of telemedicine within a large evaluation center for COVID-19 in the area of Baja California, Mexico. Our model is based on human-centric design factors and cross disciplinary collaborations for scalable data-driven enablement of smartphone, cellular, and video Teleconsul-tation technologies to link hospitals, clinics, and emergency medical services for point-of-care assessments of COVID testing, and for subsequent treatment and quar-antine decisions. A multidisciplinary team was rapidly created, in cooperation with different institutions, including: the Autonomous University of Baja California, the Ministry of Health, the Command, Communication and Computer Control Center of the Ministry of the State of Baja California (C4), Colleges of Medicine, and the College of Psychologists. Our objective is to provide information to the public and to evaluate COVID-19 in real time and to track, regional, municipal, and state-wide data in real time that informs supply chains and resource allocation with the anticipation of a surge in COVID-19 cases. RESUMEN Proporcionamos un modelo para la implementación sistemática de la telemedicina dentro de un gran centro de evaluación de COVID-19 en el área de Baja California, México. Nuestro modelo se basa en factores de diseño centrados en el ser humano y colaboraciones interdisciplinarias para la habilitación escalable basada en datos de tecnologías de teleconsulta de teléfonos inteligentes, celulares y video para vincular hospitales, clínicas y servicios médicos de emergencia para evaluaciones de COVID en el punto de atención. pruebas, y para el tratamiento posterior y decisiones de cuarentena. Rápidamente se creó un equipo multidisciplinario, en cooperación con diferentes instituciones, entre ellas: la Universidad Autónoma de Baja California, la Secretaría de Salud, el Centro de Comando, Comunicaciones y Control Informático. de la Secretaría del Estado de Baja California (C4), Facultades de Medicina y Colegio de Psicólogos. Nuestro objetivo es proporcionar información al público y evaluar COVID-19 en tiempo real y rastrear datos regionales, municipales y estatales en tiempo real que informan las cadenas de suministro y la asignación de recursos con la anticipación de un aumento de COVID-19. 19 casos.ICICT 2023: 2023 The 6th International Conference on Information and Computer Technologieshttps://doi.org/10.1007/978-981-99-3236-

Architectural model for Collaboration in The Internet of Things : a Fog Computing based approach

Through sensors, actuators and other Internet-connected devices, applications and services are becoming able to perceive and react on the real world. Seamlessly integrating people, and devices is no longer a futuristic idea. Converging the physical world with the human-made realm into one network is rather a present and promising approach called The Internet of Things (IoT). A closer look at the phenomenon of IoT reveals many problems. The current trends are focusing on Cloud-centric approaches to deal with the heterogeneity and the scale of this network. The blessing of the Cloud computing becomes, however, a burden on latency-sensitive applications, which require processing and storage mechanisms in their proximity to meet low-latency, location and better context-awareness requirements. In addition to mobility support and high geographical distribution requirements. Fog computing is a new concept that focuses on extending the Cloud paradigm to the edge of the Internet of Things, via providing communication, computing, and access management support. This research project foresees and is driven by the promising opportunities of the concept behind Fog computing. In this thesis, we leverage this new concept by delivering a Collaboration Architecture for the Fog computing. This architecture constitutes a referential model to better design and to implement Fog platforms. It powers the freedom of abstraction to make development and deployment at the Fog nodes easier and more efficient. Moreover, it provides a nest where IoT-connected objects can interact and collaborate. To this end, we introduce expressive mechanisms to define and abstract objects, data analytics, and services. To leverage Fog nodes with dynamic services and service-based collaboration, we propose the concept of Operation: a formal way to dynamically generate new services through mechanisms such as aggregation, composition, and transformation. Finally, we deliver a comprehensive study and a collaboration-oriented access control model for the proposed architecture. Dans les dernières années, les avantages du Cloud Computing l’ont mis au cœur des architectures proposées pour l’Internet des Objets (IoT). L’infrastructure homogène, prédictible et performante a fait du Cloud une solution adéquate pour le traitement et l’analyse des données en provenance des objets de l’IoT. Cependant, les avantages de l’utilisation du Cloud se révèlent problématiques pour les systèmes IoT sensibles au temps de latence, et qui exigent la distribution géographique, la prise en compte de l’environnement local ainsi que la mobilité des objets. Le Fog Computing est un nouveau concept visant l'extension du Cloud vers la périphérie de l’IoT. Ainsi, il envisage une couche de nœuds (Fogs) permettant de fournir aux objets connectés un support à la gestion de la communication, à la persistance des données et à la gestion d’accès. Ce projet de recherche est motivé par les opportunités prometteuses du concept du Fog computing. Il anticipe ces opportunités et vise à proposer une architecture fédératrice, jusqu’à présent inexistante, pour la collaboration dans le Fog. De ce fait, dans cette thèse, nous tirons parti de l'idée derrière ce nouveau concept afin de proposer une architecture à cette fin. Cette architecture consiste en un modèle référentiel qui promeut à la fois une grande abstraction dans la conception des applications, ainsi que la facilité et l'efficacité dans le développement et le déploiement au niveau des nœuds de la couche du Fog. En effet, pour renforcer ces nœuds avec des services dynamiques, nous proposons des moyens formels pour la génération dynamique de nouveaux services à travers des opérations d'agrégations, de compositions ou de transformations. En conséquence, les nœuds du Fog deviennent un nid où les objets connectés peuvent interagir et collaborer à travers des mécanismes expressifs de définition et d'abstraction d’objets, des analyses de données et des services

Journal of Telecommunications and Information Technology, 2018, nr 4

kwartalni

XIII Jornadas de ingeniería telemática (JITEL 2017)

Las Jornadas de Ingeniería Telemática (JITEL), organizadas por la Asociación de Telemática (ATEL), constituyen un foro propicio de reunión, debate y divulgación para los grupos que imparten docencia e investigan en temas relacionados con las redes y los servicios telemáticos. Con la organización de este evento se pretende fomentar, por un lado el intercambio de experiencias y resultados, además de la comunicación y cooperación entre los grupos de investigación que trabajan en temas relacionados con la telemática. En paralelo a las tradicionales sesiones que caracterizan los congresos científicos, se desea potenciar actividades más abiertas, que estimulen el intercambio de ideas entre los investigadores experimentados y los noveles, así como la creación de vínculos y puntos de encuentro entre los diferentes grupos o equipos de investigación. Para ello, además de invitar a personas relevantes en los campos correspondientes, se van a incluir sesiones de presentación y debate de las líneas y proyectos activos de los mencionados equiposLloret Mauri, J.; Casares Giner, V. (2018). XIII Jornadas de ingeniería telemática (JITEL 2017). Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/97612EDITORIA

Exploring the Boundaries of Patent Commercialization Models via Litigation

This thesis explores direct patent commercialization via patent assertion, particularly patent infringement litigation, a complex nonmarket activity whose successful undertaking requires knowledge, creativity, and financial resources, as well as a colorable infringement case. Despite these complexities, firms have increasingly employed patents as competitive tools via patent assertions, particularly in the United States. This thesis explores the business models that have been created to facilitate the direct monetization of patents. Since secrecy underpins the patent assertion strategies studied, the thesis is based on rich and enhanced secondary data. In particular, a data chaining technique has been developed to assemble relevant but disparate data into a larger coherent data set that is amenable to combination and pairing with other forms of relevant public data. This research has discovered that one particularly successful business model that employs a leveraging strategy, known as the non-practicing entity (“NPE”), has itself spawned at least two other business models, the highly capitalized “patent mass aggregator” and the “patent privateer.” The patent privateer, newly discovered in this research, is particularly interesting because it provides a way for firms to employ patents to attack competitors by forming specialized NPEs in a manner that essentially expands the boundaries of the firm. This research has also examined plaintiff firm management processes during litigations brought under leveraging and proprietary strategies, the two patent litigation strategies in which firms affirmatively initiate infringement litigations. In particular, this research investigates the commercial contexts that drive patent assertion strategies to explore the effective limits of the patent right in a litigation context. The investigation concludes that a variety of robust business models and management processes may be quite successful in extracting value from patents in the US