Let’s look at this scenario: You have a temperature sensor that publishes the current temperature to a Topic every three hours. So the question arises, if a new subscriber subscribes to this topic right after it has published the current temperature, when will this subscriber receive the temperature message? That’s right, it has to wait … Read more
In recent days, I have been preparing for the follow-up IoT STM32 development and practical demonstrations, as well as writing mini-programs, so I haven’t had time to update the articles on my public account. Actually, I originally planned to wrap up the series of articles about the IoT platform with the last one. However, a … Read more
1. Review: Overview of ROS Communication Mechanism & Similarities and Differences with MQTT Communication Overview of ROS Communication Mechanism The main communication mechanisms in ROS are as follows: 1. Topics ○ Publish/Subscribe Model: In this communication method, nodes can publish messages to a topic or subscribe to a topic to receive messages. This method is … Read more
Introduction: The First Groundbreaking Product to Introduce QUIC to MQTT In the recently released version 5.0, EMQX has innovatively introduced QUIC support. QUIC is the underlying transport protocol for the next-generation internet protocol HTTP/3. Compared to TCP/TLS protocols, it effectively reduces connection overhead and message latency, providing a flexible and efficient transport layer for modern … Read more
Author：Nanhai District Dali Town Junior High School, Foshan City, Guangdong Province Zhang Quan, Ling Yujie, Xie Hanzhe This article is sourced from “Invention and Innovation” May 2023 Junior High School Edition We found that homeroom teachers and subject teachers have many repetitive and mechanical tasks, such as: every day the homeroom teacher conveys messages from … Read more
Data packets sent by IoT smart devices must be encapsulated by the corresponding protocol at each layer. With the rapid development of Internet of Things (IoT) technology, most smart devices’ communication modules support various network communication protocols such as TCP, UDP, MQTT, CoAP, HTTP, and LwM2M, which include both transport layer and application layer protocols, … Read more
Distributed MQTT Broker Server The distributed MQTT Broker server is a message broker based on the publish/subscribe model. It supports load balancing and data synchronization across multiple nodes to provide high availability and scalability for MQTT messaging services. Here is a detailed explanation of the distributed MQTT Broker server: 1. Definition and Functionality Definition: The … Read more
Let’s dive into MQTT, how to ensure its security, and examples of the protocol to see how it has rapidly gained popularity in the IoT field. In today’s world, there are billions of smart devices. Imagine if these devices were all interconnected and could communicate with each other like their users, forming a global network. … Read more
Background From this chapter onwards, unless otherwise specified, the version of MQTT referred to in this article is 3.1.1. The MQTT protocol is one of the commonly used protocols in the Internet of Things, known as a “lightweight IoT messaging protocol”. MQTT and HTTP both belong to the seventh layer (application layer). For friends who … Read more
1. Introduction MQTT, which stands for Message Queuing Telemetry Transport, is an ISO standard (ISO/IEC PRF 20922) based on the publish/subscribe paradigm. It was released by IBM. Due to its lightweight, simple, open, and easy-to-implement characteristics, it is very suitable for IoT scenarios that require low power consumption and limited network bandwidth, such as remote … Read more