BORDER: A Benchmarking Framework for Distributed MQTT Brokers

[EN] Message queuing telemetry transport (MQTT), one of the most popular application layer protocols for the Internet of Things, works according to a publish/subscribe paradigm where clients connect to a centralized broker. Sometimes (e.g., in high scalability and low-latency applications), it is required to depart from such a centralized approach and move to a distributed one, where multiple MQTT brokers cooperate together. Many MQTT brokers (both open source or commercially available) allow to create such a distributed environment: however, it is challenging to select the right solution due to the many available choices. This article proposes, therefore benchmarking framework for distributed MQTT brokers (BORDER), a framework for creating and evaluating distributed architectures of MQTT brokers with realistic and customizable network topologies. Based on isolated Docker containers and emulated network components, the framework provides quantitative metrics about the overall system performance, such as End-to-End latency as well as network and physical resources consumed. We use BORDER to compare five of the most popular MQTT brokers that allow the creation of distributed architectures and we release it as an open-source project to allow for reproducible researches.This work was supported in part by the Project BASE5G under Project 1155850 funded by Regione Lombardia within the framework POR FESR 2014-2020.Longo, E.; Redondi, A.; Cesana, M.; Manzoni, P. (2022). BORDER: A Benchmarking Framework for Distributed MQTT Brokers. IEEE Internet of Things. 9(18):17728-17740. https://doi.org/10.1109/JIOT.2022.3155872177281774091

A LoRa-based protocol for connecting IoT edge computing nodes to provide small-data-based services

[EN] Data is becoming increasingly personal. Individuals regularly interact with a variety of structured data, ranging from SQLite databases on the phone to personal sensors and open government data. The ¿digital traces left by individuals through these interactions¿ are sometimes referred to as ¿small data¿. Examples of ¿small data¿ include driving records, biometric measurements, search histories, weather forecasts and usage alerts. In this paper, we present a flexible protocol called LoRaCTP, which is based on LoRa technology that allows data ¿chunks¿ to be transferred over large distances with very low energy expenditure. LoRaCTP provides all the mechanisms necessary to make LoRa transfer reliable by introducing a lightweight connection setup and allowing the ideal sending of an as-long-as necessary data message. We designed this protocol as communication support for small-data edge-based IoT solutions, given its stability, low power usage, and the possibility to cover long distances. We evaluated our protocol using various data content sizes and communication distances to demonstrate its performance and reliability.This work was partially supported by the "Conselleria de Innovacion, Universidades, Ciencia y Sociedad Digital", Proyectos AICO/2020, Spain, under Grant AICO/2020/302 and "Ministerio de Ciencia, Innovacion y Universidades, Programa Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad, Proyectos IDI 2018", Spain, under Grant RTI2018-096384-B-I00.Nakamura, K.; Manzoni, P.; Redondi, A.; Longo, E.; Zennaro, M.; Cano, J.; Tavares De Araujo Cesariny Calafate, CM. (2022). A LoRa-based protocol for connecting IoT edge computing nodes to provide small-data-based services. Digital Communications and Networks. 8(3):257-266. https://doi.org/10.1016/j.dcan.2021.08.0072572668

Leggere e scrivere : Un ABC della ricerca bibliografica e della composizione dei testi di ricerca

Updated version of prof. Redondi's paper about reference work. That paper is a practical guide and explains in a very simple and plan way how to find bibliographic informations on the Internet, how to write a bibliography, how to use in the right way the bibliographic citations

Charles C. Gillipsie, Adolf Youschkevitch, Lazare Carnot savant et sa contribution à la théorie de l'infini mathématique.

Redondi Pietro. Charles C. Gillipsie, Adolf Youschkevitch, Lazare Carnot savant et sa contribution à la théorie de l'infini mathématique.. In: Annales. Economies, sociétés, civilisations. 39ᵉ année, N. 1, 1984. pp. 192-196

Sadi Carnot et la recherche technologique en France de 1825 à 1850

SUMMARY. — The audience of Sadi Carnoťs ideas among the French engineers between the publication of the Reflections (1824), to whom these were addressed, and their classic discovery in the middle of the 19th century is an interesting condition for an historical comprehension of the thermodynamics' s forming. This article states the results of systematic researchs concerning the echo of Carnoťs mind. They lead to discover its theoretical presence at the origins of currents of experimental technology of heat during the first half of the century in France. This aspect is examined in Reech, Séguin and above all in Franchot, Bresson and other engineers by unknown documents. The article particularly shows then the development of air engines in this period aimed at carrying out the principles expressed by Carnoťs theory.RÉSUMÉ. — L'audience chez les ingénieurs français des idées de Sadi Carnot entre la parution des Réflexions (1824), auxquels elles étaient adressées, et leur classique redécouverte à la moitié du XIXe siècle représente une condition intéressante pour la compréhension historique de la formation de la thermodynamique. On fait part ici des résultats de recherches systématiques sur l'écho de la pensée de Carnot aboutissant à la découverte de sa présence théorique à l'origine de courants de technologie expérimentale de la chaleur pendant la première moitié du siècle en France. On examine cet aspect chez Reech, Séguin et surtout chez Franchot, Bresson et d'autres ingénieurs par des documents jusqu'à présent inconnus. On montre, en particulier, que l'étude des machines à air à cette période visait à réaliser les principes de la théorie de Carnot.Redondi Pietro. Sadi Carnot et la recherche technologique en France de 1825 à 1850. In: Revue d'histoire des sciences, tome 29, n°3, 1976. pp. 243-259

Les tensions actuelles de l'histoire des sciences

Redondi Pietro. Les tensions actuelles de l'histoire des sciences. In: Annales. Économies, Sociétés, Civilisations. 36ᵉ année, N. 4, 1981. pp. 572-590